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4 daysMerge tag 'mm-stable-2025-07-30-15-25' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "As usual, many cleanups. The below blurbiage describes 42 patchsets. 21 of those are partially or fully cleanup work. "cleans up", "cleanup", "maintainability", "rationalizes", etc. I never knew the MM code was so dirty. "mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes) addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly mapped VMAs were not eligible for merging with existing adjacent VMAs. "mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park) adds a new kernel module which simplifies the setup and usage of DAMON in production environments. "stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig) is a cleanup to the writeback code which removes a couple of pointers from struct writeback_control. "drivers/base/node.c: optimization and cleanups" (Donet Tom) contains largely uncorrelated cleanups to the NUMA node setup and management code. "mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman) does some maintenance work on the userfaultfd code. "Readahead tweaks for larger folios" (Ryan Roberts) implements some tuneups for pagecache readahead when it is reading into order>0 folios. "selftests/mm: Tweaks to the cow test" (Mark Brown) provides some cleanups and consistency improvements to the selftests code. "Optimize mremap() for large folios" (Dev Jain) does that. A 37% reduction in execution time was measured in a memset+mremap+munmap microbenchmark. "Remove zero_user()" (Matthew Wilcox) expunges zero_user() in favor of the more modern memzero_page(). "mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand) addresses some warts which David noticed in the huge page code. These were not known to be causing any issues at this time. "mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park) provides some cleanup and consolidation work in DAMON. "use vm_flags_t consistently" (Lorenzo Stoakes) uses vm_flags_t in places where we were inappropriately using other types. "mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy) increases the reliability of large page allocation in the memfd code. "mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple) removes several now-unneeded PFN_* flags. "mm/damon: decouple sysfs from core" (SeongJae Park) implememnts some cleanup and maintainability work in the DAMON sysfs layer. "madvise cleanup" (Lorenzo Stoakes) does quite a lot of cleanup/maintenance work in the madvise() code. "madvise anon_name cleanups" (Vlastimil Babka) provides additional cleanups on top or Lorenzo's effort. "Implement numa node notifier" (Oscar Salvador) creates a standalone notifier for NUMA node memory state changes. Previously these were lumped under the more general memory on/offline notifier. "Make MIGRATE_ISOLATE a standalone bit" (Zi Yan) cleans up the pageblock isolation code and fixes a potential issue which doesn't seem to cause any problems in practice. "selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park) adds additional drgn- and python-based DAMON selftests which are more comprehensive than the existing selftest suite. "Misc rework on hugetlb faulting path" (Oscar Salvador) fixes a rather obscure deadlock in the hugetlb fault code and follows that fix with a series of cleanups. "cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport) rationalizes and cleans up the highmem-specific code in the CMA allocator. "mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand) provides cleanups and future-preparedness to the migration code. "mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park) adds some tracepoints to some DAMON auto-tuning code. "mm/damon: fix misc bugs in DAMON modules" (SeongJae Park) does that. "mm/damon: misc cleanups" (SeongJae Park) also does what it claims. "mm: folio_pte_batch() improvements" (David Hildenbrand) cleans up the large folio PTE batching code. "mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park) facilitates dynamic alteration of DAMON's inter-node allocation policy. "Remove unmap_and_put_page()" (Vishal Moola) provides a couple of page->folio conversions. "mm: per-node proactive reclaim" (Davidlohr Bueso) implements a per-node control of proactive reclaim - beyond the current memcg-based implementation. "mm/damon: remove damon_callback" (SeongJae Park) replaces the damon_callback interface with a more general and powerful damon_call()+damos_walk() interface. "mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes) implements a number of mremap cleanups (of course) in preparation for adding new mremap() functionality: newly permit the remapping of multiple VMAs when the user is specifying MREMAP_FIXED. It still excludes some specialized situations where this cannot be performed reliably. "drop hugetlb_free_pgd_range()" (Anthony Yznaga) switches some sparc hugetlb code over to the generic version and removes the thus-unneeded hugetlb_free_pgd_range(). "mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park) augments the present userspace-requested update of DAMON sysfs monitoring files. Automatic update is now provided, along with a tunable to control the update interval. "Some randome fixes and cleanups to swapfile" (Kemeng Shi) does what is claims. "mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand) provides (and uses) a means by which debug-style functions can grab a copy of a pageframe and inspect it locklessly without tripping over the races inherent in operating on the live pageframe directly. "use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan) addresses the large contention issues which can be triggered by reads from that procfs file. Latencies are reduced by more than half in some situations. The series also introduces several new selftests for the /proc/pid/maps interface. "__folio_split() clean up" (Zi Yan) cleans up __folio_split()! "Optimize mprotect() for large folios" (Dev Jain) provides some quite large (>3x) speedups to mprotect() when dealing with large folios. "selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian) does some cleanup work in the selftests code. "tools/testing: expand mremap testing" (Lorenzo Stoakes) extends the mremap() selftest in several ways, including adding more checking of Lorenzo's recently added "permit mremap() move of multiple VMAs" feature. "selftests/damon/sysfs.py: test all parameters" (SeongJae Park) extends the DAMON sysfs interface selftest so that it tests all possible user-requested parameters. Rather than the present minimal subset" * tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits) MAINTAINERS: add missing headers to mempory policy & migration section MAINTAINERS: add missing file to cgroup section MAINTAINERS: add MM MISC section, add missing files to MISC and CORE MAINTAINERS: add missing zsmalloc file MAINTAINERS: add missing files to page alloc section MAINTAINERS: add missing shrinker files MAINTAINERS: move memremap.[ch] to hotplug section MAINTAINERS: add missing mm_slot.h file THP section MAINTAINERS: add missing interval_tree.c to memory mapping section MAINTAINERS: add missing percpu-internal.h file to per-cpu section mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info() selftests/damon: introduce _common.sh to host shared function selftests/damon/sysfs.py: test runtime reduction of DAMON parameters selftests/damon/sysfs.py: test non-default parameters runtime commit selftests/damon/sysfs.py: generalize DAMON context commit assertion selftests/damon/sysfs.py: generalize monitoring attributes commit assertion selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion selftests/damon/sysfs.py: test DAMOS filters commitment selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion selftests/damon/sysfs.py: test DAMOS destinations commitment ...
5 daysMerge tag 'slab-for-6.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab Pull slab updates from Vlastimil Babka: - Convert struct slab to its own flags instead of referencing page flags, which is another preparation step before separating it from struct page completely. Along with that, a bunch of documentation fixes and cleanups (Matthew Wilcox) - Convert large kmalloc to use frozen pages in order to be consistent with non-large kmalloc slabs (Vlastimil Babka) - MAINTAINERS updates (Matthew Wilcox, Lorenzo Stoakes) - Restore NUMA policy support for large kmalloc, broken by mistake in v6.1 (Vlastimil Babka) * tag 'slab-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: MAINTAINERS: add missing files to slab section slab: Update MAINTAINERS entry memcg_slabinfo: Fix use of PG_slab kfence: Remove mention of PG_slab vmcoreinfo: Remove documentation of PG_slab and PG_hugetlb doc: Add slab internal kernel-doc slub: Fix a documentation build error for krealloc() slab: Add SL_pfmemalloc flag slab: Add SL_partial flag slab: Rename slab->__page_flags to slab->flags doc: Move SLUB documentation to the admin guide mm, slab: use frozen pages for large kmalloc mm, slab: restore NUMA policy support for large kmalloc
5 daysMerge tag 'net-next-6.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core & protocols: - Wrap datapath globals into net_aligned_data, to avoid false sharing - Preserve MSG_ZEROCOPY in forwarding (e.g. out of a container) - Add SO_INQ and SCM_INQ support to AF_UNIX - Add SIOCINQ support to AF_VSOCK - Add TCP_MAXSEG sockopt to MPTCP - Add IPv6 force_forwarding sysctl to enable forwarding per interface - Make TCP validation of whether packet fully fits in the receive window and the rcv_buf more strict. With increased use of HW aggregation a single "packet" can be multiple 100s of kB - Add MSG_MORE flag to optimize large TCP transmissions via sockmap, improves latency up to 33% for sockmap users - Convert TCP send queue handling from tasklet to BH workque - Improve BPF iteration over TCP sockets to see each socket exactly once - Remove obsolete and unused TCP RFC3517/RFC6675 loss recovery code - Support enabling kernel threads for NAPI processing on per-NAPI instance basis rather than a whole device. Fully stop the kernel NAPI thread when threaded NAPI gets disabled. Previously thread would stick around until ifdown due to tricky synchronization - Allow multicast routing to take effect on locally-generated packets - Add output interface argument for End.X in segment routing - MCTP: add support for gateway routing, improve bind() handling - Don't require rtnl_lock when fetching an IPv6 neighbor over Netlink - Add a new neighbor flag ("extern_valid"), which cedes refresh responsibilities to userspace. This is needed for EVPN multi-homing where a neighbor entry for a multi-homed host needs to be synced across all the VTEPs among which the host is multi-homed - Support NUD_PERMANENT for proxy neighbor entries - Add a new queuing discipline for IETF RFC9332 DualQ Coupled AQM - Add sequence numbers to netconsole messages. Unregister netconsole's console when all net targets are removed. Code refactoring. Add a number of selftests - Align IPSec inbound SA lookup to RFC 4301. Only SPI and protocol should be used for an inbound SA lookup - Support inspecting ref_tracker state via DebugFS - Don't force bonding advertisement frames tx to ~333 ms boundaries. Add broadcast_neighbor option to send ARP/ND on all bonded links - Allow providing upcall pid for the 'execute' command in openvswitch - Remove DCCP support from Netfilter's conntrack - Disallow multiple packet duplications in the queuing layer - Prevent use of deprecated iptables code on PREEMPT_RT Driver API: - Support RSS and hashing configuration over ethtool Netlink - Add dedicated ethtool callbacks for getting and setting hashing fields - Add support for power budget evaluation strategy in PSE / Power-over-Ethernet. Generate Netlink events for overcurrent etc - Support DPLL phase offset monitoring across all device inputs. Support providing clock reference and SYNC over separate DPLL inputs - Support traffic classes in devlink rate API for bandwidth management - Remove rtnl_lock dependency from UDP tunnel port configuration Device drivers: - Add a new Broadcom driver for 800G Ethernet (bnge) - Add a standalone driver for Microchip ZL3073x DPLL - Remove IBM's NETIUCV device driver - Ethernet high-speed NICs: - Broadcom (bnxt): - support zero-copy Tx of DMABUF memory - take page size into account for page pool recycling rings - Intel (100G, ice, idpf): - idpf: XDP and AF_XDP support preparations - idpf: add flow steering - add link_down_events statistic - clean up the TSPLL code - preparations for live VM migration - nVidia/Mellanox: - support zero-copy Rx/Tx interfaces (DMABUF and io_uring) - optimize context memory usage for matchers - expose serial numbers in devlink info - support PCIe congestion metrics - Meta (fbnic): - add 25G, 50G, and 100G link modes to phylink - support dumping FW logs - Marvell/Cavium: - support for CN20K generation of the Octeon chips - Amazon: - add HW clock (without timestamping, just hypervisor time access) - Ethernet virtual: - VirtIO net: - support segmentation of UDP-tunnel-encapsulated packets - Google (gve): - support packet timestamping and clock synchronization - Microsoft vNIC: - add handler for device-originated servicing events - allow dynamic MSI-X vector allocation - support Tx bandwidth clamping - Ethernet NICs consumer, and embedded: - AMD: - amd-xgbe: hardware timestamping and PTP clock support - Broadcom integrated MACs (bcmgenet, bcmasp): - use napi_complete_done() return value to support NAPI polling - add support for re-starting auto-negotiation - Broadcom switches (b53): - support BCM5325 switches - add bcm63xx EPHY power control - Synopsys (stmmac): - lots of code refactoring and cleanups - TI: - icssg-prueth: read firmware-names from device tree - icssg: PRP offload support - Microchip: - lan78xx: convert to PHYLINK for improved PHY and MAC management - ksz: add KSZ8463 switch support - Intel: - support similar queue priority scheme in multi-queue and time-sensitive networking (taprio) - support packet pre-emption in both - RealTek (r8169): - enable EEE at 5Gbps on RTL8126 - Airoha: - add PPPoE offload support - MDIO bus controller for Airoha AN7583 - Ethernet PHYs: - support for the IPQ5018 internal GE PHY - micrel KSZ9477 switch-integrated PHYs: - add MDI/MDI-X control support - add RX error counters - add cable test support - add Signal Quality Indicator (SQI) reporting - dp83tg720: improve reset handling and reduce link recovery time - support bcm54811 (and its MII-Lite interface type) - air_en8811h: support resume/suspend - support PHY counters for QCA807x and QCA808x - support WoL for QCA807x - CAN drivers: - rcar_canfd: support for Transceiver Delay Compensation - kvaser: report FW versions via devlink dev info - WiFi: - extended regulatory info support (6 GHz) - add statistics and beacon monitor for Multi-Link Operation (MLO) - support S1G aggregation, improve S1G support - add Radio Measurement action fields - support per-radio RTS threshold - some work around how FIPS affects wifi, which was wrong (RC4 is used by TKIP, not only WEP) - improvements for unsolicited probe response handling - WiFi drivers: - RealTek (rtw88): - IBSS mode for SDIO devices - RealTek (rtw89): - BT coexistence for MLO/WiFi7 - concurrent station + P2P support - support for USB devices RTL8851BU/RTL8852BU - Intel (iwlwifi): - use embedded PNVM in (to be released) FW images to fix compatibility issues - many cleanups (unused FW APIs, PCIe code, WoWLAN) - some FIPS interoperability - MediaTek (mt76): - firmware recovery improvements - more MLO work - Qualcomm/Atheros (ath12k): - fix scan on multi-radio devices - more EHT/Wi-Fi 7 features - encapsulation/decapsulation offload - Broadcom (brcm80211): - support SDIO 43751 device - Bluetooth: - hci_event: add support for handling LE BIG Sync Lost event - ISO: add socket option to report packet seqnum via CMSG - ISO: support SCM_TIMESTAMPING for ISO TS - Bluetooth drivers: - intel_pcie: support Function Level Reset - nxpuart: add support for 4M baudrate - nxpuart: implement powerup sequence, reset, FW dump, and FW loading" * tag 'net-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1742 commits) dpll: zl3073x: Fix build failure selftests: bpf: fix legacy netfilter options ipv6: annotate data-races around rt->fib6_nsiblings ipv6: fix possible infinite loop in fib6_info_uses_dev() ipv6: prevent infinite loop in rt6_nlmsg_size() ipv6: add a retry logic in net6_rt_notify() vrf: Drop existing dst reference in vrf_ip6_input_dst net/sched: taprio: align entry index attr validation with mqprio net: fsl_pq_mdio: use dev_err_probe selftests: rtnetlink.sh: remove esp4_offload after test vsock: remove unnecessary null check in vsock_getname() igb: xsk: solve negative overflow of nb_pkts in zerocopy mode stmmac: xsk: fix negative overflow of budget in zerocopy mode dt-bindings: ieee802154: Convert at86rf230.txt yaml format net: dsa: microchip: Disable PTP function of KSZ8463 net: dsa: microchip: Setup fiber ports for KSZ8463 net: dsa: microchip: Write switch MAC address differently for KSZ8463 net: dsa: microchip: Use different registers for KSZ8463 net: dsa: microchip: Add KSZ8463 switch support to KSZ DSA driver dt-bindings: net: dsa: microchip: Add KSZ8463 switch support ...
10 daysmm/util: introduce snapshot_page()Luiz Capitulino
This commit refactors __dump_page() into snapshot_page(). snapshot_page() tries to take a faithful snapshot of a page and its folio representation. The snapshot is returned in the struct page_snapshot parameter along with additional flags that are best retrieved at snapshot creation time to reduce race windows. This function is intended to be used by callers that need a stable representation of a struct page and struct folio so that pointers or page information doesn't change while working on a page. The idea and original implementation of snapshot_page() comes from Matthew Wilcox with suggestions for improvements from David Hildenbrand. All bugs and misconceptions are mine. [luizcap@redhat.com: fix set_ps_flags() commentary] Link: https://lkml.kernel.org/r/d5c75701-b353-4536-a306-187fab0655b3@redhat.com Link: https://lkml.kernel.org/r/637a03a05cb2e3df88f84ff9e9f9642374ef813a.1752499009.git.luizcap@redhat.com Signed-off-by: Luiz Capitulino <luizcap@redhat.com> Reviewed-by: Shivank Garg <shivankg@amd.com> Tested-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
11 daysnetmem, mlx4: access ->pp_ref_count through netmem_desc instead of pageByungchul Park
To eliminate the use of struct page in page pool, the page pool users should use netmem descriptor and APIs instead. Make mlx4 access ->pp_ref_count through netmem_desc instead of page. While at it, add a helper, pp_page_to_nmdesc() and __pp_page_to_nmdesc(), that can be used to get netmem_desc from page only if it's a pp page. For now that netmem_desc overlays on page, it can be achieved by just casting, and use macro and _Generic to cover const casting as well. Plus, change page_pool_page_is_pp() to check for 'const struct page *' instead of 'struct page *' since it doesn't modify data and additionally covers const type. Signed-off-by: Byungchul Park <byungchul@sk.com> Link: https://patch.msgid.link/20250721021835.63939-4-byungchul@sk.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
13 daysMerge branch 'acpi-apei'Rafael J. Wysocki
Merge ACPI APEI updates for 6.17-rc1: - Fix iomem-related sparse warnings in the APEI EINJ driver (Zaid Alali, Tony Luck) - Add EINJv2 error injection support to the APEI EINJ driver (Zaid Alali) - Fix memory corruption in error_type_set() in the APEI EINJ driver (Dan Carpenter) - Fix less than zero comparison on a size_t variable in the APEI EINJ driver (Colin Ian King) - Fix check and iounmap of an uninitialized pointer in the APEI EINJ driver (Colin Ian King) - Add TAINT_MACHINE_CHECK to the GHES panic path in APEI to improve diagnostics and post-mortem analysis (Breno Leitao) - Update APEI reviewer records in MAINTAINERS (Rafael Wysocki) - Fix the handling of synchronous uncorrected memory errors in APEI (Shuai Xue) * acpi-apei: ACPI: APEI: handle synchronous exceptions in task work ACPI: APEI: send SIGBUS to current task if synchronous memory error not recovered ACPI: APEI: MAINTAINERS: Update reviewers for APEI ACPI: APEI: EINJ: Fix trigger actions ACPI: APEI: GHES: add TAINT_MACHINE_CHECK on GHES panic path ACPI: APEI: EINJ: Fix check and iounmap of uninitialized pointer p ACPI: APEI: EINJ: Fix less than zero comparison on a size_t variable ACPI: APEI: EINJ: prevent memory corruption in error_type_set() ACPI: APEI: EINJ: Update the documentation for EINJv2 support ACPI: APEI: EINJ: Enable EINJv2 error injections ACPI: APEI: EINJ: Create debugfs files to enter device id and syndrome ACPI: APEI: EINJ: Discover EINJv2 parameters ACPI: APEI: EINJ: Add einjv2 extension struct ACPI: APEI: EINJ: Enable the discovery of EINJv2 capabilities ACPI: APEI: EINJ: Fix kernel test sparse warnings
2025-07-16ACPI: APEI: handle synchronous exceptions in task workShuai Xue
The memory uncorrected error could be signaled by asynchronous interrupt (specifically, SPI in arm64 platform), e.g. when an error is detected by a background scrubber, or signaled by synchronous exception (specifically, data abort exception in arm64 platform), e.g. when a CPU tries to access a poisoned cache line. Currently, both synchronous and asynchronous errors use memory_failure_queue() to schedule memory_failure() to exectute in a kworker context. As a result, when a user-space process is accessing a poisoned data, a data abort is taken and the memory_failure() is executed in the kworker context, which: - will send wrong si_code by SIGBUS signal in early_kill mode, and - can not kill the user-space in some cases resulting a synchronous error infinite loop Issue 1: send wrong si_code in early_kill mode Since commit a70297d22132 ("ACPI: APEI: set memory failure flags as MF_ACTION_REQUIRED on synchronous events")', the flag MF_ACTION_REQUIRED could be used to determine whether a synchronous exception occurs on ARM64 platform. When a synchronous exception is detected, the kernel is expected to terminate the current process which has accessed a poisoned page. This is done by sending a SIGBUS signal with error code BUS_MCEERR_AR, indicating an action-required machine check error on read. However, when kill_proc() is called to terminate the processes who has the poisoned page mapped, it sends the incorrect SIGBUS error code BUS_MCEERR_AO because the context in which it operates is not the one where the error was triggered. To reproduce this problem: #sysctl -w vm.memory_failure_early_kill=1 vm.memory_failure_early_kill = 1 # STEP2: inject an UCE error and consume it to trigger a synchronous error #einj_mem_uc single 0: single vaddr = 0xffffb0d75400 paddr = 4092d55b400 injecting ... triggering ... signal 7 code 5 addr 0xffffb0d75000 page not present Test passed The si_code (code 5) from einj_mem_uc indicates that it is BUS_MCEERR_AO error and it is not factually correct. After this change: # STEP1: enable early kill mode #sysctl -w vm.memory_failure_early_kill=1 vm.memory_failure_early_kill = 1 # STEP2: inject an UCE error and consume it to trigger a synchronous error #einj_mem_uc single 0: single vaddr = 0xffffb0d75400 paddr = 4092d55b400 injecting ... triggering ... signal 7 code 4 addr 0xffffb0d75000 page not present Test passed The si_code (code 4) from einj_mem_uc indicates that it is a BUS_MCEERR_AR error as expected. Issue 2: a synchronous error infinite loop If a user-space process, e.g. devmem, accesses a poisoned page for which the HWPoison flag is set, kill_accessing_process() is called to send SIGBUS to current processs with error info. Since the memory_failure() is executed in the kworker context, it will just do nothing but return EFAULT. So, devmem will access the posioned page and trigger an exception again, resulting in a synchronous error infinite loop. Such exception loop may cause platform firmware to exceed some threshold and reboot when Linux could have recovered from this error. To reproduce this problem: # STEP 1: inject an UCE error, and kernel will set HWPosion flag for related page #einj_mem_uc single 0: single vaddr = 0xffffb0d75400 paddr = 4092d55b400 injecting ... triggering ... signal 7 code 4 addr 0xffffb0d75000 page not present Test passed # STEP 2: access the same page and it will trigger a synchronous error infinite loop devmem 0x4092d55b400 To fix above two issues, queue memory_failure() as a task_work so that it runs in the context of the process that is actually consuming the poisoned data. Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com> Tested-by: Ma Wupeng <mawupeng1@huawei.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Xiaofei Tan <tanxiaofei@huawei.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Jane Chu <jane.chu@oracle.com> Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com> Reviewed-by: Hanjun Guo <guohanjun@huawei.com> Link: https://patch.msgid.link/20250714114212.31660-3-xueshuai@linux.alibaba.com [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-07-13mm: simplify folio_expected_ref_count()David Hildenbrand
Now that PAGE_MAPPING_MOVABLE is gone, we can simplify and rely on the folio_test_anon() test only. ... but staring at the users, this function should never even have been called on movable_ops pages. E.g., * __buffer_migrate_folio() does not make sense for them * folio_migrate_mapping() does not make sense for them * migrate_huge_page_move_mapping() does not make sense for them * __migrate_folio() does not make sense for them * ... and khugepaged should never stumble over them Let's simply refuse typed pages (which includes slab) except hugetlb, and WARN. Link: https://lkml.kernel.org/r/20250704102524.326966-26-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Brendan Jackman <jackmanb@google.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Christian Brauner <brauner@kernel.org> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Eugenio Pé rez <eperezma@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Gregory Price <gourry@gourry.net> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Jan Kara <jack@suse.cz> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jason Wang <jasowang@redhat.com> Cc: Jerrin Shaji George <jerrin.shaji-george@broadcom.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Mathew Brost <matthew.brost@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Rik van Riel <riel@surriel.com> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Cc: xu xin <xu.xin16@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-13mm, madvise: extract mm code from prctl_set_vma() to mm/madvise.cVlastimil Babka
Setting anon_name is done via madvise_set_anon_name() and behaves a lot of like other madvise operations. However, apparently because madvise() has lacked the 4th argument and prctl() not, the userspace entry point has been implemented via prctl(PR_SET_VMA, ...) and handled first by prctl_set_vma(). Currently prctl_set_vma() lives in kernel/sys.c but setting the vma->anon_name is mm-specific code so extract it to a new set_anon_vma_name() function under mm. mm/madvise.c seems to be the most straightforward place as that's where madvise_set_anon_name() lives. Stop declaring the latter in mm.h and instead declare set_anon_vma_name(). Link: https://lkml.kernel.org/r/20250624-anon_name_cleanup-v2-2-600075462a11@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Hildenbrand <david@redhat.com> Tested-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Colin Cross <ccross@google.com> Cc: Jann Horn <jannh@google.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-12Merge branch 'mm-hotfixes-stable' into mm-stable to pick up changes whichAndrew Morton
are required for a merge of the series "mm: folio_pte_batch() improvements".
2025-07-09mm: remove callers of pfn_t functionalityAlistair Popple
All PFN_* pfn_t flags have been removed. Therefore there is no longer a need for the pfn_t type and all uses can be replaced with normal pfns. Link: https://lkml.kernel.org/r/bbedfa576c9822f8032494efbe43544628698b1f.1750323463.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Balbir Singh <balbirs@nvidia.com> Cc: Björn Töpel <bjorn@kernel.org> Cc: Björn Töpel <bjorn@rivosinc.com> Cc: Chunyan Zhang <zhang.lyra@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Deepak Gupta <debug@rivosinc.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Inki Dae <m.szyprowski@samsung.com> Cc: John Groves <john@groves.net> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09mm: remove devmap related functions and page table bitsAlistair Popple
Now that DAX and all other reference counts to ZONE_DEVICE pages are managed normally there is no need for the special devmap PTE/PMD/PUD page table bits. So drop all references to these, freeing up a software defined page table bit on architectures supporting it. Link: https://lkml.kernel.org/r/6389398c32cc9daa3dfcaa9f79c7972525d310ce.1750323463.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Acked-by: Will Deacon <will@kernel.org> # arm64 Acked-by: David Hildenbrand <david@redhat.com> Suggested-by: Chunyan Zhang <zhang.lyra@gmail.com> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Balbir Singh <balbirs@nvidia.com> Cc: Björn Töpel <bjorn@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Deepak Gupta <debug@rivosinc.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Inki Dae <m.szyprowski@samsung.com> Cc: John Groves <john@groves.net> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09mm: update core kernel code to use vm_flags_t consistentlyLorenzo Stoakes
The core kernel code is currently very inconsistent in its use of vm_flags_t vs. unsigned long. This prevents us from changing the type of vm_flags_t in the future and is simply not correct, so correct this. While this results in rather a lot of churn, it is a critical pre-requisite for a future planned change to VMA flag type. Additionally, update VMA userland tests to account for the changes. To make review easier and to break things into smaller parts, driver and architecture-specific changes is left for a subsequent commit. The code has been adjusted to cascade the changes across all calling code as far as is needed. We will adjust architecture-specific and driver code in a subsequent patch. Overall, this patch does not introduce any functional change. Link: https://lkml.kernel.org/r/d1588e7bb96d1ea3fe7b9df2c699d5b4592d901d.1750274467.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Kees Cook <kees@kernel.org> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Jan Kara <jack@suse.cz> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Acked-by: Zi Yan <ziy@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Jann Horn <jannh@google.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09mm: change vm_get_page_prot() to accept vm_flags_t argumentLorenzo Stoakes
Patch series "use vm_flags_t consistently". The VMA flags field vma->vm_flags is of type vm_flags_t. Right now this is exactly equivalent to unsigned long, but it should not be assumed to be. Much code that references vma->vm_flags already correctly uses vm_flags_t, but a fairly large chunk of code simply uses unsigned long and assumes that the two are equivalent. This series corrects that and has us use vm_flags_t consistently. This series is motivated by the desire to, in a future series, adjust vm_flags_t to be a u64 regardless of whether the kernel is 32-bit or 64-bit in order to deal with the VMA flag exhaustion issue and avoid all the various problems that arise from it (being unable to use certain features in 32-bit, being unable to add new flags except for 64-bit, etc.) This is therefore a critical first step towards that goal. At any rate, using the correct type is of value regardless. We additionally take the opportunity to refer to VMA flags as vm_flags where possible to make clear what we're referring to. Overall, this series does not introduce any functional change. This patch (of 3): We abstract the type of the VMA flags to vm_flags_t, however in may places it is simply assumed this is unsigned long, which is simply incorrect. At the moment this is simply an incongruity, however in future we plan to change this type and therefore this change is a critical requirement for doing so. Overall, this patch does not introduce any functional change. [lorenzo.stoakes@oracle.com: add missing vm_get_page_prot() instance, remove include] Link: https://lkml.kernel.org/r/552f88e1-2df8-4e95-92b8-812f7c8db829@lucifer.local Link: https://lkml.kernel.org/r/cover.1750274467.git.lorenzo.stoakes@oracle.com Link: https://lkml.kernel.org/r/a12769720a2743f235643b158c4f4f0a9911daf0.1750274467.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64] Acked-by: Zi Yan <ziy@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Jann Horn <jannh@google.com> Cc: Kees Cook <kees@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09mm/huge_memory: don't mark refcounted folios special in vmf_insert_folio_pud()David Hildenbrand
Marking PUDs that map a "normal" refcounted folios as special is against our rules documented for vm_normal_page(). normal (refcounted) folios shall never have the page table mapping marked as special. Fortunately, there are not that many pud_special() check that can be mislead and are right now rather harmless: e.g., none so far bases decisions whether to grab a folio reference on that decision. Well, and GUP-fast will fallback to GUP-slow. All in all, so far no big implications as it seems. Getting this right will get more important as we introduce folio_normal_page_pud() and start using it in more place where we currently special-case based on other VMA flags. Fix it just like we fixed vmf_insert_folio_pmd(). Add folio_mk_pud() to mimic what we do with folio_mk_pmd(). Link: https://lkml.kernel.org/r/20250613092702.1943533-4-david@redhat.com Fixes: dbe54153296d ("mm/huge_memory: add vmf_insert_folio_pud()") Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Alistair Popple <apopple@nvidia.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mariano Pache <npache@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09mm: fix the inaccurate memory statistics issue for usersBaolin Wang
On some large machines with a high number of CPUs running a 64K pagesize kernel, we found that the 'RES' field is always 0 displayed by the top command for some processes, which will cause a lot of confusion for users. PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 875525 root 20 0 12480 0 0 R 0.3 0.0 0:00.08 top 1 root 20 0 172800 0 0 S 0.0 0.0 0:04.52 systemd The main reason is that the batch size of the percpu counter is quite large on these machines, caching a significant percpu value, since converting mm's rss stats into percpu_counter by commit f1a7941243c1 ("mm: convert mm's rss stats into percpu_counter"). Intuitively, the batch number should be optimized, but on some paths, performance may take precedence over statistical accuracy. Therefore, introducing a new interface to add the percpu statistical count and display it to users, which can remove the confusion. In addition, this change is not expected to be on a performance-critical path, so the modification should be acceptable. In addition, the 'mm->rss_stat' is updated by using add_mm_counter() and dec/inc_mm_counter(), which are all wrappers around percpu_counter_add_batch(). In percpu_counter_add_batch(), there is percpu batch caching to avoid 'fbc->lock' contention. This patch changes task_mem() and task_statm() to get the accurate mm counters under the 'fbc->lock', but this should not exacerbate kernel 'mm->rss_stat' lock contention due to the percpu batch caching of the mm counters. The following test also confirm the theoretical analysis. I run the stress-ng that stresses anon page faults in 32 threads on my 32 cores machine, while simultaneously running a script that starts 32 threads to busy-loop pread each stress-ng thread's /proc/pid/status interface. From the following data, I did not observe any obvious impact of this patch on the stress-ng tests. w/o patch: stress-ng: info: [6848] 4,399,219,085,152 CPU Cycles 67.327 B/sec stress-ng: info: [6848] 1,616,524,844,832 Instructions 24.740 B/sec (0.367 instr. per cycle) stress-ng: info: [6848] 39,529,792 Page Faults Total 0.605 M/sec stress-ng: info: [6848] 39,529,792 Page Faults Minor 0.605 M/sec w/patch: stress-ng: info: [2485] 4,462,440,381,856 CPU Cycles 68.382 B/sec stress-ng: info: [2485] 1,615,101,503,296 Instructions 24.750 B/sec (0.362 instr. per cycle) stress-ng: info: [2485] 39,439,232 Page Faults Total 0.604 M/sec stress-ng: info: [2485] 39,439,232 Page Faults Minor 0.604 M/sec On comparing a very simple app which just allocates & touches some memory against v6.1 (which doesn't have f1a7941243c1) and latest Linus tree (4c06e63b9203) I can see that on latest Linus tree the values for VmRSS, RssAnon and RssFile from /proc/self/status are all zeroes while they do report values on v6.1 and a Linus tree with this patch. Link: https://lkml.kernel.org/r/f4586b17f66f97c174f7fd1f8647374fdb53de1c.1749119050.git.baolin.wang@linux.alibaba.com Fixes: f1a7941243c1 ("mm: convert mm's rss stats into percpu_counter") Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Aboorva Devarajan <aboorvad@linux.ibm.com> Tested-by: Aboorva Devarajan <aboorvad@linux.ibm.com> Tested-by Donet Tom <donettom@linux.ibm.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: SeongJae Park <sj@kernel.org> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: David Hildenbrand <david@redhat.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-06-17mm, slab: use frozen pages for large kmallocVlastimil Babka
Since slab pages are now frozen, it makes sense to have large kmalloc() objects behave same as small kmalloc(), as the choice between the two is an implementation detail depending on allocation size. Notably, increasing refcount on a slab page containing kmalloc() object is not possible anymore, so it should be consistent for large kmalloc pages. Therefore, change large kmalloc to use the frozen pages API. Because of some unexpected fallout in the slab pages case (see commit b9c0e49abfca ("mm: decline to manipulate the refcount on a slab page"), implement the same kind of checks and warnings as part of this change. Notably, networking code using sendpage_ok() to determine whether the page refcount can be manipulated in the network stack should continue behaving correctly. Before this change, the function returns true for large kmalloc pages and page refcount can be manipulated. After this change, the function will return false. Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Harry Yoo <harry.yoo@oracle.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2025-06-02Merge tag 'mm-stable-2025-06-01-14-06' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - "zram: support algorithm-specific parameters" from Sergey Senozhatsky adds infrastructure for passing algorithm-specific parameters into zram. A single parameter `winbits' is implemented at this time. - "memcg: nmi-safe kmem charging" from Shakeel Butt makes memcg charging nmi-safe, which is required by BFP, which can operate in NMI context. - "Some random fixes and cleanup to shmem" from Kemeng Shi implements small fixes and cleanups in the shmem code. - "Skip mm selftests instead when kernel features are not present" from Zi Yan fixes some issues in the MM selftest code. - "mm/damon: build-enable essential DAMON components by default" from SeongJae Park reworks DAMON Kconfig to make it easier to enable CONFIG_DAMON. - "sched/numa: add statistics of numa balance task migration" from Libo Chen adds more info into sysfs and procfs files to improve visibility into the NUMA balancer's task migration activity. - "selftests/mm: cow and gup_longterm cleanups" from Mark Brown provides various updates to some of the MM selftests to make them play better with the overall containing framework. * tag 'mm-stable-2025-06-01-14-06' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (43 commits) mm/khugepaged: clean up refcount check using folio_expected_ref_count() selftests/mm: fix test result reporting in gup_longterm selftests/mm: report unique test names for each cow test selftests/mm: add helper for logging test start and results selftests/mm: use standard ksft_finished() in cow and gup_longterm selftests/damon/_damon_sysfs: skip testcases if CONFIG_DAMON_SYSFS is disabled sched/numa: add statistics of numa balance task sched/numa: fix task swap by skipping kernel threads tools/testing: check correct variable in open_procmap() tools/testing/vma: add missing function stub mm/gup: update comment explaining why gup_fast() disables IRQs selftests/mm: two fixes for the pfnmap test mm/khugepaged: fix race with folio split/free using temporary reference mm: add CONFIG_PAGE_BLOCK_ORDER to select page block order mmu_notifiers: remove leftover stub macros selftests/mm: deduplicate test names in madv_populate kcov: rust: add flags for KCOV with Rust mm: rust: make CONFIG_MMU ifdefs more narrow mmu_gather: move tlb flush for VM_PFNMAP/VM_MIXEDMAP vmas into free_pgtables() mm/damon/Kconfig: enable CONFIG_DAMON by default ...
2025-05-31mm: rename page->index to page->__folio_indexMatthew Wilcox (Oracle)
All users of page->index have been converted to not refer to it any more. Update a few pieces of documentation that were missed and prevent new users from appearing (or at least make them easy to grep for). Link: https://lkml.kernel.org/r/20250514181508.3019795-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-31Merge tag 'mm-stable-2025-05-31-14-50' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "Add folio_mk_pte()" from Matthew Wilcox simplifies the act of creating a pte which addresses the first page in a folio and reduces the amount of plumbing which architecture must implement to provide this. - "Misc folio patches for 6.16" from Matthew Wilcox is a shower of largely unrelated folio infrastructure changes which clean things up and better prepare us for future work. - "memory,x86,acpi: hotplug memory alignment advisement" from Gregory Price adds early-init code to prevent x86 from leaving physical memory unused when physical address regions are not aligned to memory block size. - "mm/compaction: allow more aggressive proactive compaction" from Michal Clapinski provides some tuning of the (sadly, hard-coded (more sadly, not auto-tuned)) thresholds for our invokation of proactive compaction. In a simple test case, the reduction of a guest VM's memory consumption was dramatic. - "Minor cleanups and improvements to swap freeing code" from Kemeng Shi provides some code cleaups and a small efficiency improvement to this part of our swap handling code. - "ptrace: introduce PTRACE_SET_SYSCALL_INFO API" from Dmitry Levin adds the ability for a ptracer to modify syscalls arguments. At this time we can alter only "system call information that are used by strace system call tampering, namely, syscall number, syscall arguments, and syscall return value. This series should have been incorporated into mm.git's "non-MM" branch, but I goofed. - "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions" from Andrei Vagin extends the info returned by the PAGEMAP_SCAN ioctl against /proc/pid/pagemap. This permits CRIU to more efficiently get at the info about guard regions. - "Fix parameter passed to page_mapcount_is_type()" from Gavin Shan implements that fix. No runtime effect is expected because validate_page_before_insert() happens to fix up this error. - "kernel/events/uprobes: uprobe_write_opcode() rewrite" from David Hildenbrand basically brings uprobe text poking into the current decade. Remove a bunch of hand-rolled implementation in favor of using more current facilities. - "mm/ptdump: Drop assumption that pxd_val() is u64" from Anshuman Khandual provides enhancements and generalizations to the pte dumping code. This might be needed when 128-bit Page Table Descriptors are enabled for ARM. - "Always call constructor for kernel page tables" from Kevin Brodsky ensures that the ctor/dtor is always called for kernel pgtables, as it already is for user pgtables. This permits the addition of more functionality such as "insert hooks to protect page tables". This change does result in various architectures performing unnecesary work, but this is fixed up where it is anticipated to occur. - "Rust support for mm_struct, vm_area_struct, and mmap" from Alice Ryhl adds plumbing to permit Rust access to core MM structures. - "fix incorrectly disallowed anonymous VMA merges" from Lorenzo Stoakes takes advantage of some VMA merging opportunities which we've been missing for 15 years. - "mm/madvise: batch tlb flushes for MADV_DONTNEED and MADV_FREE" from SeongJae Park optimizes process_madvise()'s TLB flushing. Instead of flushing each address range in the provided iovec, we batch the flushing across all the iovec entries. The syscall's cost was approximately halved with a microbenchmark which was designed to load this particular operation. - "Track node vacancy to reduce worst case allocation counts" from Sidhartha Kumar makes the maple tree smarter about its node preallocation. stress-ng mmap performance increased by single-digit percentages and the amount of unnecessarily preallocated memory was dramaticelly reduced. - "mm/gup: Minor fix, cleanup and improvements" from Baoquan He removes a few unnecessary things which Baoquan noted when reading the code. - ""Enhance sysfs handling for memory hotplug in weighted interleave" from Rakie Kim "enhances the weighted interleave policy in the memory management subsystem by improving sysfs handling, fixing memory leaks, and introducing dynamic sysfs updates for memory hotplug support". Fixes things on error paths which we are unlikely to hit. - "mm/damon: auto-tune DAMOS for NUMA setups including tiered memory" from SeongJae Park introduces new DAMOS quota goal metrics which eliminate the manual tuning which is required when utilizing DAMON for memory tiering. - "mm/vmalloc.c: code cleanup and improvements" from Baoquan He provides cleanups and small efficiency improvements which Baoquan found via code inspection. - "vmscan: enforce mems_effective during demotion" from Gregory Price changes reclaim to respect cpuset.mems_effective during demotion when possible. because presently, reclaim explicitly ignores cpuset.mems_effective when demoting, which may cause the cpuset settings to violated. This is useful for isolating workloads on a multi-tenant system from certain classes of memory more consistently. - "Clean up split_huge_pmd_locked() and remove unnecessary folio pointers" from Gavin Guo provides minor cleanups and efficiency gains in in the huge page splitting and migrating code. - "Use kmem_cache for memcg alloc" from Huan Yang creates a slab cache for `struct mem_cgroup', yielding improved memory utilization. - "add max arg to swappiness in memory.reclaim and lru_gen" from Zhongkun He adds a new "max" argument to the "swappiness=" argument for memory.reclaim MGLRU's lru_gen. This directs proactive reclaim to reclaim from only anon folios rather than file-backed folios. - "kexec: introduce Kexec HandOver (KHO)" from Mike Rapoport is the first step on the path to permitting the kernel to maintain existing VMs while replacing the host kernel via file-based kexec. At this time only memblock's reserve_mem is preserved. - "mm: Introduce for_each_valid_pfn()" from David Woodhouse provides and uses a smarter way of looping over a pfn range. By skipping ranges of invalid pfns. - "sched/numa: Skip VMA scanning on memory pinned to one NUMA node via cpuset.mems" from Libo Chen removes a lot of pointless VMA scanning when a task is pinned a single NUMA mode. Dramatic performance benefits were seen in some real world cases. - "JFS: Implement migrate_folio for jfs_metapage_aops" from Shivank Garg addresses a warning which occurs during memory compaction when using JFS. - "move all VMA allocation, freeing and duplication logic to mm" from Lorenzo Stoakes moves some VMA code from kernel/fork.c into the more appropriate mm/vma.c. - "mm, swap: clean up swap cache mapping helper" from Kairui Song provides code consolidation and cleanups related to the folio_index() function. - "mm/gup: Cleanup memfd_pin_folios()" from Vishal Moola does that. - "memcg: Fix test_memcg_min/low test failures" from Waiman Long addresses some bogus failures which are being reported by the test_memcontrol selftest. - "eliminate mmap() retry merge, add .mmap_prepare hook" from Lorenzo Stoakes commences the deprecation of file_operations.mmap() in favor of the new file_operations.mmap_prepare(). The latter is more restrictive and prevents drivers from messing with things in ways which, amongst other problems, may defeat VMA merging. - "memcg: decouple memcg and objcg stocks"" from Shakeel Butt decouples the per-cpu memcg charge cache from the objcg's one. This is a step along the way to making memcg and objcg charging NMI-safe, which is a BPF requirement. - "mm/damon: minor fixups and improvements for code, tests, and documents" from SeongJae Park is yet another batch of miscellaneous DAMON changes. Fix and improve minor problems in code, tests and documents. - "memcg: make memcg stats irq safe" from Shakeel Butt converts memcg stats to be irq safe. Another step along the way to making memcg charging and stats updates NMI-safe, a BPF requirement. - "Let unmap_hugepage_range() and several related functions take folio instead of page" from Fan Ni provides folio conversions in the hugetlb code. * tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (285 commits) mm: pcp: increase pcp->free_count threshold to trigger free_high mm/hugetlb: convert use of struct page to folio in __unmap_hugepage_range() mm/hugetlb: refactor __unmap_hugepage_range() to take folio instead of page mm/hugetlb: refactor unmap_hugepage_range() to take folio instead of page mm/hugetlb: pass folio instead of page to unmap_ref_private() memcg: objcg stock trylock without irq disabling memcg: no stock lock for cpu hot-unplug memcg: make __mod_memcg_lruvec_state re-entrant safe against irqs memcg: make count_memcg_events re-entrant safe against irqs memcg: make mod_memcg_state re-entrant safe against irqs memcg: move preempt disable to callers of memcg_rstat_updated memcg: memcg_rstat_updated re-entrant safe against irqs mm: khugepaged: decouple SHMEM and file folios' collapse selftests/eventfd: correct test name and improve messages alloc_tag: check mem_profiling_support in alloc_tag_init Docs/damon: update titles and brief introductions to explain DAMOS selftests/damon/_damon_sysfs: read tried regions directories in order mm/damon/tests/core-kunit: add a test for damos_set_filters_default_reject() mm/damon/paddr: remove unused variable, folio_list, in damon_pa_stat() mm/damon/sysfs-schemes: fix wrong comment on damons_sysfs_quota_goal_metric_strs ...
2025-05-28Merge tag 'net-next-6.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Paolo Abeni: "Core: - Implement the Device Memory TCP transmit path, allowing zero-copy data transmission on top of TCP from e.g. GPU memory to the wire. - Move all the IPv6 routing tables management outside the RTNL scope, under its own lock and RCU. The route control path is now 3x times faster. - Convert queue related netlink ops to instance lock, reducing again the scope of the RTNL lock. This improves the control plane scalability. - Refactor the software crc32c implementation, removing unneeded abstraction layers and improving significantly the related micro-benchmarks. - Optimize the GRO engine for UDP-tunneled traffic, for a 10% performance improvement in related stream tests. - Cover more per-CPU storage with local nested BH locking; this is a prep work to remove the current per-CPU lock in local_bh_disable() on PREMPT_RT. - Introduce and use nlmsg_payload helper, combining buffer bounds verification with accessing payload carried by netlink messages. Netfilter: - Rewrite the procfs conntrack table implementation, improving considerably the dump performance. A lot of user-space tools still use this interface. - Implement support for wildcard netdevice in netdev basechain and flowtables. - Integrate conntrack information into nft trace infrastructure. - Export set count and backend name to userspace, for better introspection. BPF: - BPF qdisc support: BPF-qdisc can be implemented with BPF struct_ops programs and can be controlled in similar way to traditional qdiscs using the "tc qdisc" command. - Refactor the UDP socket iterator, addressing long standing issues WRT duplicate hits or missed sockets. Protocols: - Improve TCP receive buffer auto-tuning and increase the default upper bound for the receive buffer; overall this improves the single flow maximum thoughput on 200Gbs link by over 60%. - Add AFS GSSAPI security class to AF_RXRPC; it provides transport security for connections to the AFS fileserver and VL server. - Improve TCP multipath routing, so that the sources address always matches the nexthop device. - Introduce SO_PASSRIGHTS for AF_UNIX, to allow disabling SCM_RIGHTS, and thus preventing DoS caused by passing around problematic FDs. - Retire DCCP socket. DCCP only receives updates for bugs, and major distros disable it by default. Its removal allows for better organisation of TCP fields to reduce the number of cache lines hit in the fast path. - Extend TCP drop-reason support to cover PAWS checks. Driver API: - Reorganize PTP ioctl flag support to require an explicit opt-in for the drivers, avoiding the problem of drivers not rejecting new unsupported flags. - Converted several device drivers to timestamping APIs. - Introduce per-PHY ethtool dump helpers, improving the support for dump operations targeting PHYs. Tests and tooling: - Add support for classic netlink in user space C codegen, so that ynl-c can now read, create and modify links, routes addresses and qdisc layer configuration. - Add ynl sub-types for binary attributes, allowing ynl-c to output known struct instead of raw binary data, clarifying the classic netlink output. - Extend MPTCP selftests to improve the code-coverage. - Add tests for XDP tail adjustment in AF_XDP. New hardware / drivers: - OpenVPN virtual driver: offload OpenVPN data channels processing to the kernel-space, increasing the data transfer throughput WRT the user-space implementation. - Renesas glue driver for the gigabit ethernet RZ/V2H(P) SoC. - Broadcom asp-v3.0 ethernet driver. - AMD Renoir ethernet device. - ReakTek MT9888 2.5G ethernet PHY driver. - Aeonsemi 10G C45 PHYs driver. Drivers: - Ethernet high-speed NICs: - nVidia/Mellanox (mlx5): - refactor the steering table handling to significantly reduce the amount of memory used - add support for complex matches in H/W flow steering - improve flow streeing error handling - convert to netdev instance locking - Intel (100G, ice, igb, ixgbe, idpf): - ice: add switchdev support for LLDP traffic over VF - ixgbe: add firmware manipulation and regions devlink support - igb: introduce support for frame transmission premption - igb: adds persistent NAPI configuration - idpf: introduce RDMA support - idpf: add initial PTP support - Meta (fbnic): - extend hardware stats coverage - add devlink dev flash support - Broadcom (bnxt): - add support for RX-side device memory TCP - Wangxun (txgbe): - implement support for udp tunnel offload - complete PTP and SRIOV support for AML 25G/10G devices - Ethernet NICs embedded and virtual: - Google (gve): - add device memory TCP TX support - Amazon (ena): - support persistent per-NAPI config - Airoha: - add H/W support for L2 traffic offload - add per flow stats for flow offloading - RealTek (rtl8211): add support for WoL magic packet - Synopsys (stmmac): - dwmac-socfpga 1000BaseX support - add Loongson-2K3000 support - introduce support for hardware-accelerated VLAN stripping - Broadcom (bcmgenet): - expose more H/W stats - Freescale (enetc, dpaa2-eth): - enetc: add MAC filter, VLAN filter RSS and loopback support - dpaa2-eth: convert to H/W timestamping APIs - vxlan: convert FDB table to rhashtable, for better scalabilty - veth: apply qdisc backpressure on full ring to reduce TX drops - Ethernet switches: - Microchip (kzZ88x3): add ETS scheduler support - Ethernet PHYs: - RealTek (rtl8211): - add support for WoL magic packet - add support for PHY LEDs - CAN: - Adds RZ/G3E CANFD support to the rcar_canfd driver. - Preparatory work for CAN-XL support. - Add self-tests framework with support for CAN physical interfaces. - WiFi: - mac80211: - scan improvements with multi-link operation (MLO) - Qualcomm (ath12k): - enable AHB support for IPQ5332 - add monitor interface support to QCN9274 - add multi-link operation support to WCN7850 - add 802.11d scan offload support to WCN7850 - monitor mode for WCN7850, better 6 GHz regulatory - Qualcomm (ath11k): - restore hibernation support - MediaTek (mt76): - WiFi-7 improvements - implement support for mt7990 - Intel (iwlwifi): - enhanced multi-link single-radio (EMLSR) support on 5 GHz links - rework device configuration - RealTek (rtw88): - improve throughput for RTL8814AU - RealTek (rtw89): - add multi-link operation support - STA/P2P concurrency improvements - support different SAR configs by antenna - Bluetooth: - introduce HCI Driver protocol - btintel_pcie: do not generate coredump for diagnostic events - btusb: add HCI Drv commands for configuring altsetting - btusb: add RTL8851BE device 0x0bda:0xb850 - btusb: add new VID/PID 13d3/3584 for MT7922 - btusb: add new VID/PID 13d3/3630 and 13d3/3613 for MT7925 - btnxpuart: implement host-wakeup feature" * tag 'net-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1611 commits) selftests/bpf: Fix bpf selftest build warning selftests: netfilter: Fix skip of wildcard interface test net: phy: mscc: Stop clearing the the UDPv4 checksum for L2 frames net: openvswitch: Fix the dead loop of MPLS parse calipso: Don't call calipso functions for AF_INET sk. selftests/tc-testing: Add a test for HFSC eltree double add with reentrant enqueue behaviour on netem net_sched: hfsc: Address reentrant enqueue adding class to eltree twice octeontx2-pf: QOS: Refactor TC_HTB_LEAF_DEL_LAST callback octeontx2-pf: QOS: Perform cache sync on send queue teardown net: mana: Add support for Multi Vports on Bare metal net: devmem: ncdevmem: remove unused variable net: devmem: ksft: upgrade rx test to send 1K data net: devmem: ksft: add 5 tuple FS support net: devmem: ksft: add exit_wait to make rx test pass net: devmem: ksft: add ipv4 support net: devmem: preserve sockc_err page_pool: fix ugly page_pool formatting net: devmem: move list_add to net_devmem_bind_dmabuf. selftests: netfilter: nft_queue.sh: include file transfer duration in log message net: phy: mscc: Fix memory leak when using one step timestamping ...
2025-05-22mm: convert do_set_pmd() to take a folioBaolin Wang
In do_set_pmd(), we always use the folio->page to build PMD mappings for the entire folio. Since all callers of do_set_pmd() already hold a stable folio, converting do_set_pmd() to take a folio is safe and more straightforward. In addition, to ensure the extensibility of do_set_pmd() for supporting larger folios beyond PMD size, we keep the 'page' parameter to specify which page within the folio should be mapped. No functional changes expected. Link: https://lkml.kernel.org/r/9b488f4ecb4d3fd8634e3d448dd0ed6964482480.1747017104.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Mariano Pache <npache@redhat.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-22mm: remove VM_PATDavid Hildenbrand
It's unused, so let's remove it. Link: https://lkml.kernel.org/r/20250512123424.637989-7-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Ingo Molnar <mingo@kernel.org> [x86 bits] Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Dave Airlie <airlied@gmail.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Jann Horn <jannh@google.com> Cc: Jonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Tvrtko Ursulin <tursulin@ursulin.net> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-20mm: fix VM_UFFD_MINOR == VM_SHADOW_STACK on USERFAULTFD=y && ARM64_GCS=yFlorent Revest
On configs with CONFIG_ARM64_GCS=y, VM_SHADOW_STACK is bit 38. On configs with CONFIG_HAVE_ARCH_USERFAULTFD_MINOR=y (selected by CONFIG_ARM64 when CONFIG_USERFAULTFD=y), VM_UFFD_MINOR is _also_ bit 38. This bit being shared by two different VMA flags could lead to all sorts of unintended behaviors. Presumably, a process could maybe call into userfaultfd in a way that disables the shadow stack vma flag. I can't think of any attack where this would help (presumably, if an attacker tries to disable shadow stacks, they are trying to hijack control flow so can't arbitrarily call into userfaultfd yet anyway) but this still feels somewhat scary. Link: https://lkml.kernel.org/r/20250507131000.1204175-2-revest@chromium.org Fixes: ae80e1629aea ("mm: Define VM_SHADOW_STACK for arm64 when we support GCS") Signed-off-by: Florent Revest <revest@chromium.org> Reviewed-by: Mark Brown <broonie@kernel.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Brendan Jackman <jackmanb@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Florent Revest <revest@chromium.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12mm: establish mm/vma_exec.c for shared exec/mm VMA functionalityLorenzo Stoakes
Patch series "move all VMA allocation, freeing and duplication logic to mm", v3. Currently VMA allocation, freeing and duplication exist in kernel/fork.c, which is a violation of separation of concerns, and leaves these functions exposed to the rest of the kernel when they are in fact internal implementation details. Resolve this by moving this logic to mm, and making it internal to vma.c, vma.h. This also allows us, in future, to provide userland testing around this functionality. We additionally abstract dup_mmap() to mm, being careful to ensure kernel/fork.c acceses this via the mm internal header so it is not exposed elsewhere in the kernel. As part of this change, also abstract initial stack allocation performed in __bprm_mm_init() out of fs code into mm via the create_init_stack_vma(), as this code uses vm_area_alloc() and vm_area_free(). In order to do so sensibly, we introduce a new mm/vma_exec.c file, which contains the code that is shared by mm and exec. This file is added to both memory mapping and exec sections in MAINTAINERS so both sets of maintainers can maintain oversight. As part of this change, we also move relocate_vma_down() to mm/vma_exec.c so all shared mm/exec functionality is kept in one place. We add code shared between nommu and mmu-enabled configurations in order to share VMA allocation, freeing and duplication code correctly while also keeping these functions available in userland VMA testing. This is achieved by adding a mm/vma_init.c file which is also compiled by the userland tests. This patch (of 4): There is functionality that overlaps the exec and memory mapping subsystems. While it properly belongs in mm, it is important that exec maintainers maintain oversight of this functionality correctly. We can establish both goals by adding a new mm/vma_exec.c file which contains these 'glue' functions, and have fs/exec.c import them. As a part of this change, to ensure that proper oversight is achieved, add the file to both the MEMORY MAPPING and EXEC & BINFMT API, ELF sections. scripts/get_maintainer.pl can correctly handle files in multiple entries and this neatly handles the cross-over. [akpm@linux-foundation.org: fix comment typo] Link: https://lkml.kernel.org/r/80f0d0c6-0b68-47f9-ab78-0ab7f74677fc@lucifer.local Link: https://lkml.kernel.org/r/cover.1745853549.git.lorenzo.stoakes@oracle.com Link: https://lkml.kernel.org/r/91f2cee8f17d65214a9d83abb7011aa15f1ea690.1745853549.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12mm: add folio_expected_ref_count() for reference count calculationShivank Garg
Patch series " JFS: Implement migrate_folio for jfs_metapage_aops" v5. This patchset addresses a warning that occurs during memory compaction due to JFS's missing migrate_folio operation. The warning was introduced by commit 7ee3647243e5 ("migrate: Remove call to ->writepage") which added explicit warnings when filesystem don't implement migrate_folio. The syzbot reported following [1]: jfs_metapage_aops does not implement migrate_folio WARNING: CPU: 1 PID: 5861 at mm/migrate.c:955 fallback_migrate_folio mm/migrate.c:953 [inline] WARNING: CPU: 1 PID: 5861 at mm/migrate.c:955 move_to_new_folio+0x70e/0x840 mm/migrate.c:1007 Modules linked in: CPU: 1 UID: 0 PID: 5861 Comm: syz-executor280 Not tainted 6.15.0-rc1-next-20250411-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:fallback_migrate_folio mm/migrate.c:953 [inline] RIP: 0010:move_to_new_folio+0x70e/0x840 mm/migrate.c:1007 To fix this issue, this series implement metapage_migrate_folio() for JFS which handles both single and multiple metapages per page configurations. While most filesystems leverage existing migration implementations like filemap_migrate_folio(), buffer_migrate_folio_norefs() or buffer_migrate_folio() (which internally used folio_expected_refs()), JFS's metapage architecture requires special handling of its private data during migration. To support this, this series introduce the folio_expected_ref_count(), which calculates external references to a folio from page/swap cache, private data, and page table mappings. This standardized implementation replaces the previous ad-hoc folio_expected_refs() function and enables JFS to accurately determine whether a folio has unexpected references before attempting migration. Implement folio_expected_ref_count() to calculate expected folio reference counts from: - Page/swap cache (1 per page) - Private data (1) - Page table mappings (1 per map) While originally needed for page migration operations, this improved implementation standardizes reference counting by consolidating all refcount contributors into a single, reusable function that can benefit any subsystem needing to detect unexpected references to folios. The folio_expected_ref_count() returns the sum of these external references without including any reference the caller itself might hold. Callers comparing against the actual folio_ref_count() must account for their own references separately. Link: https://syzkaller.appspot.com/bug?extid=8bb6fd945af4e0ad9299 [1] Link: https://lkml.kernel.org/r/20250430100150.279751-1-shivankg@amd.com Link: https://lkml.kernel.org/r/20250430100150.279751-2-shivankg@amd.com Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Shivank Garg <shivankg@amd.com> Suggested-by: Matthew Wilcox <willy@infradead.org> Co-developed-by: David Hildenbrand <david@redhat.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12mm/rmap: inline folio_test_large_maybe_mapped_shared() into callersLance Yang
To prevent the function from being used when CONFIG_MM_ID is disabled, we intend to inline it into its few callers, which also would help maintain the expected code placement. Link: https://lkml.kernel.org/r/20250424155606.57488-1-lance.yang@linux.dev Signed-off-by: Lance Yang <lance.yang@linux.dev> Suggested-by: David Hildenbrand <david@redhat.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Mingzhe Yang <mingzhe.yang@ly.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: move mmap/vma locking logic into specific filesLorenzo Stoakes
Currently the VMA and mmap locking logic is entangled in two of the most overwrought files in mm - include/linux/mm.h and mm/memory.c. Separate this logic out so we can more easily make changes and create an appropriate MAINTAINERS entry that spans only the logic relating to locking. This should have no functional change. Care is taken to avoid dependency loops, we must regrettably keep release_fault_lock() and assert_fault_locked() in mm.h as a result due to the dependence on the vm_fault type. Additionally we must declare rcuwait_wake_up() manually to avoid a dependency cycle on linux/rcuwait.h. Additionally move the nommu implementatino of lock_mm_and_find_vma() to mmap_lock.c so everything lock-related is in one place. Link: https://lkml.kernel.org/r/bec6c8e29fa8de9267a811a10b1bdae355d67ed4.1744799282.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: David Hildenbrand <david@redhat.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: SeongJae Park <sj@kernel.org> Cc: Shakeel Butt <shakeel.butt@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: skip ptlock_init() for kernel PMDsKevin Brodsky
Split page table locks are not used for pgtables associated to init_mm, at any level. pte_alloc_kernel() does not call ptlock_init() as a result. There is however no separate alloc/free functions for kernel PMDs, and pmd_ptlock_init() is called unconditionally. When ALLOC_SPLIT_PTLOCKS is true (e.g. 32-bit architectures or if CONFIG_PREEMPT_RT is selected), this results in unnecessary dynamic memory allocation every time a kernel PMD is allocated. Now that pagetable_pmd_ctor() is passed the associated mm, we can easily remove this overhead by skipping pmd_ptlock_init() if the pgtable is associated to init_mm. No special-casing is needed on the dtor path, as ptlock_free() is already called unconditionally for all levels. (ptlock_free() is a no-op unless a ptlock was allocated for the given PTP.) Link: https://lkml.kernel.org/r/20250408095222.860601-8-kevin.brodsky@arm.com Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Linus Waleij <linus.walleij@linaro.org> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mike Rapoport <rppt@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Will Deacon <will@kernel.org> Cc: <x86@kernel.org> Cc: Yang Shi <yang@os.amperecomputing.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: call ctor/dtor for kernel PTEsKevin Brodsky
Since [1], constructors/destructors are expected to be called for all page table pages, at all levels and for both user and kernel pgtables. There is however one glaring exception: kernel PTEs are managed via separate helpers (pte_alloc_kernel/pte_free_kernel), which do not call the [cd]tor, at least not in the generic implementation. The most obvious reason for this anomaly is that init_mm is special-cased not to use split page table locks. As a result calling ptlock_init() for PTEs associated with init_mm would be wasteful, potentially resulting in dynamic memory allocation. However, pgtable [cd]tors perform other actions - currently related to accounting/statistics, and potentially more functionally significant in the future. Now that pagetable_pte_ctor() is passed the associated mm, we can make it skip the call to ptlock_init() for init_mm; this allows us to call the ctor from pte_alloc_one_kernel() too. This is matched by a call to the pgtable destructor in pte_free_kernel(); no special-casing is needed on that path, as ptlock_free() is already called unconditionally. (ptlock_free() is a no-op unless a ptlock was allocated for the given PTP.) This patch ensures that all architectures that rely on <asm-generic/pgalloc.h> call the [cd]tor for kernel PTEs. pte_free_kernel() cannot be overridden so changing the generic implementation is sufficient. pte_alloc_one_kernel() can be overridden using __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL, and a few architectures implement it by calling the page allocator directly. We amend those so that they call the generic __pte_alloc_one_kernel() instead, if possible, ensuring that the ctor is called. A few architectures do not use <asm-generic/pgalloc.h>; those will be taken care of separately. [1] https://lore.kernel.org/linux-mm/20250103184415.2744423-1-kevin.brodsky@arm.com/ Link: https://lkml.kernel.org/r/20250408095222.860601-4-kevin.brodsky@arm.com Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> # s390 Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Linus Waleij <linus.walleij@linaro.org> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mike Rapoport <rppt@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Will Deacon <will@kernel.org> Cc: <x86@kernel.org> Cc: Yang Shi <yang@os.amperecomputing.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: pass mm down to pagetable_{pte,pmd}_ctorKevin Brodsky
Patch series "Always call constructor for kernel page tables", v2. There has been much confusion around exactly when page table constructors/destructors (pagetable_*_[cd]tor) are supposed to be called. They were initially introduced for user PTEs only (to support split page table locks), then at the PMD level for the same purpose. Accounting was added later on, starting at the PTE level and then moving to higher levels (PMD, PUD). Finally, with my earlier series "Account page tables at all levels" [1], the ctor/dtor is run for all levels, all the way to PGD. I thought this was the end of the story, and it hopefully is for user pgtables, but I was wrong for what concerns kernel pgtables. The current situation there makes very little sense: * At the PTE level, the ctor/dtor is not called (at least in the generic implementation). Specific helpers are used for kernel pgtables at this level (pte_{alloc,free}_kernel()) and those have never called the ctor/dtor, most likely because they were initially irrelevant in the kernel case. * At all other levels, the ctor/dtor is normally called. This is potentially wasteful at the PMD level (more on that later). This series aims to ensure that the ctor/dtor is always called for kernel pgtables, as it already is for user pgtables. Besides consistency, the main motivation is to guarantee that ctor/dtor hooks are systematically called; this makes it possible to insert hooks to protect page tables [2], for instance. There is however an extra challenge: split locks are not used for kernel pgtables, and it would therefore be wasteful to initialise them (ptlock_init()). It is worth clarifying exactly when split locks are used. They clearly are for user pgtables, but as illustrated in commit 61444cde9170 ("ARM: 8591/1: mm: use fully constructed struct pages for EFI pgd allocations"), they also are for special page tables like efi_mm. The one case where split locks are definitely unused is pgtables owned by init_mm; this is consistent with the behaviour of apply_to_pte_range(). The approach chosen in this series is therefore to pass the mm associated to the pgtables being constructed to pagetable_{pte,pmd}_ctor() (patch 1), and skip ptlock_init() if mm == &init_mm (patch 3 and 7). This makes it possible to call the PTE ctor/dtor from pte_{alloc,free}_kernel() without unintended consequences (patch 3). As a result the accounting functions are now called at all levels for kernel pgtables, and split locks are never initialised. In configurations where ptlocks are dynamically allocated (32-bit, PREEMPT_RT, etc.) and ARCH_ENABLE_SPLIT_PMD_PTLOCK is selected, this series results in the removal of a kmem_cache allocation for every kernel PMD. Additionally, for certain architectures that do not use <asm-generic/pgalloc.h> such as s390, the same optimisation occurs at the PTE level. === Things get more complicated when it comes to special pgtable allocators (patch 8-12). All architectures need such allocators to create initial kernel pgtables; we are not concerned with those as the ctor cannot be called so early in the boot sequence. However, those allocators may also be used later in the boot sequence or during normal operations. There are two main use-cases: 1. Mapping EFI memory: efi_mm (arm, arm64, riscv) 2. arch_add_memory(): init_mm The ctor is already explicitly run (at the PTE/PMD level) in the first case, as required for pgtables that are not associated with init_mm. However the same allocators may also be used for the second use-case (or others), and this is where it gets messy. Patch 1 calls the ctor with NULL as mm in those situations, as the actual mm isn't available. Practically this means that ptlocks will be unconditionally initialised. This is fine on arm - create_mapping_late() is only used for the EFI mapping. On arm64, __create_pgd_mapping() is also used by arch_add_memory(); patch 8/9/11 ensure that ctors are called at all levels with the appropriate mm. The situation is similar on riscv, but propagating the mm down to the ctor would require significant refactoring. Since they are already called unconditionally, this series leaves riscv no worse off - patch 10 adds comments to clarify the situation. From a cursory look at other architectures implementing arch_add_memory(), s390 and x86 may also need a similar treatment to add constructor calls. This is to be taken care of in a future version or as a follow-up. === The complications in those special pgtable allocators beg the question: does it really make sense to treat efi_mm and init_mm differently in e.g. apply_to_pte_range()? Maybe what we really need is a way to tell if an mm corresponds to user memory or not, and never use split locks for non-user mm's. Feedback and suggestions welcome! This patch (of 12): In preparation for calling constructors for all kernel page tables while eliding unnecessary ptlock initialisation, let's pass down the associated mm to the PTE/PMD level ctors. (These are the two levels where ptlocks are used.) In most cases the mm is already around at the point of calling the ctor so we simply pass it down. This is however not the case for special page table allocators: * arch/arm/mm/mmu.c * arch/arm64/mm/mmu.c * arch/riscv/mm/init.c In those cases, the page tables being allocated are either for standard kernel memory (init_mm) or special page directories, which may not be associated to any mm. For now let's pass NULL as mm; this will be refined where possible in future patches. No functional change in this patch. Link: https://lore.kernel.org/linux-mm/20250103184415.2744423-1-kevin.brodsky@arm.com/ [1] Link: https://lore.kernel.org/linux-hardening/20250203101839.1223008-1-kevin.brodsky@arm.com/ [2] Link: https://lkml.kernel.org/r/20250408095222.860601-1-kevin.brodsky@arm.com Link: https://lkml.kernel.org/r/20250408095222.860601-2-kevin.brodsky@arm.com Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> [s390] Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Linus Waleij <linus.walleij@linaro.org> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mike Rapoport <rppt@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Yang Shi <yang@os.amperecomputing.com> Cc: <x86@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: annotate data race in update_hiwater_rssIgnacio Encinas
mm_struct.hiwater_rss can be accessed concurrently without proper synchronization as reported by KCSAN. This data race is benign as it only affects accounting information. Annotate it with data_race() to make KCSAN happy. Link: https://lkml.kernel.org/r/20250331-mm-maxrss-data-race-v2-1-cf958e6205bf@iencinas.com Signed-off-by: Ignacio Encinas <ignacio@iencinas.com> Reported-by: syzbot+419c4b42acc36c420ad3@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/67e3390c.050a0220.1ec46.0001.GAE@google.com/ Suggested-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Pedro Falcato <pfalcato@suse.de> Cc: Liam Howlett <liam.howlett@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: delete thp_nr_pages()Matthew Wilcox (Oracle)
All callers now use folio_nr_pages(). Delete this wrapper. Link: https://lkml.kernel.org/r/20250402210612.2444135-9-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: remove offset_in_thp()Matthew Wilcox (Oracle)
All callers have been converted to call offset_in_folio(). Link: https://lkml.kernel.org/r/20250402210612.2444135-3-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: add folio_mk_pmd()Matthew Wilcox (Oracle)
Removes five conversions from folio to page. Also removes both callers of mk_pmd() that aren't part of mk_huge_pmd(), getting us a step closer to removing the confusion between mk_pmd(), mk_huge_pmd() and pmd_mkhuge(). Link: https://lkml.kernel.org/r/20250402181709.2386022-11-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Muchun Song <muchun.song@linux.dev> Cc: Richard Weinberger <richard@nod.at> Cc: <x86@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: add folio_mk_pte()Matthew Wilcox (Oracle)
Remove a cast from folio to page in four callers of mk_pte(). Link: https://lkml.kernel.org/r/20250402181709.2386022-8-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Muchun Song <muchun.song@linux.dev> Cc: Richard Weinberger <richard@nod.at> Cc: <x86@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: make mk_pte() definition unconditionalMatthew Wilcox (Oracle)
All architectures now use the common mk_pte() definition, so we can remove the condition. Link: https://lkml.kernel.org/r/20250402181709.2386022-7-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Muchun Song <muchun.song@linux.dev> Cc: Richard Weinberger <richard@nod.at> Cc: <x86@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm: introduce a common definition of mk_pte()Matthew Wilcox (Oracle)
Most architectures simply call pfn_pte(). Centralise that as the normal definition and remove the definition of mk_pte() from the architectures which have either that exact definition or something similar. Link: https://lkml.kernel.org/r/20250402181709.2386022-3-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> # s390 Cc: Zi Yan <ziy@nvidia.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Muchun Song <muchun.song@linux.dev> Cc: Richard Weinberger <richard@nod.at> Cc: <x86@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-04-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.15-rc4). This pull includes wireless and a fix to vxlan which isn't in Linus's tree just yet. The latter creates with a silent conflict / build breakage, so merging it now to avoid causing problems. drivers/net/vxlan/vxlan_vnifilter.c 094adad91310 ("vxlan: Use a single lock to protect the FDB table") 087a9eb9e597 ("vxlan: vnifilter: Fix unlocked deletion of default FDB entry") https://lore.kernel.org/20250423145131.513029-1-idosch@nvidia.com No "normal" conflicts, or adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-17fs/dax: fix folio splitting issue by resetting old folio order + _nr_pagesDavid Hildenbrand
Alison reports an issue with fsdax when large extends end up using large ZONE_DEVICE folios: [ 417.796271] BUG: kernel NULL pointer dereference, address: 0000000000000b00 [ 417.796982] #PF: supervisor read access in kernel mode [ 417.797540] #PF: error_code(0x0000) - not-present page [ 417.798123] PGD 2a5c5067 P4D 2a5c5067 PUD 2a5c6067 PMD 0 [ 417.798690] Oops: Oops: 0000 [#1] SMP NOPTI [ 417.799178] CPU: 5 UID: 0 PID: 1515 Comm: mmap Tainted: ... [ 417.800150] Tainted: [O]=OOT_MODULE [ 417.800583] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 [ 417.801358] RIP: 0010:__lruvec_stat_mod_folio+0x7e/0x250 [ 417.801948] Code: ... [ 417.803662] RSP: 0000:ffffc90002be3a08 EFLAGS: 00010206 [ 417.804234] RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000000002 [ 417.804984] RDX: ffffffff815652d7 RSI: 0000000000000000 RDI: ffffffff82a2beae [ 417.805689] RBP: ffffc90002be3a28 R08: 0000000000000000 R09: 0000000000000000 [ 417.806384] R10: ffffea0007000040 R11: ffff888376ffe000 R12: 0000000000000001 [ 417.807099] R13: 0000000000000012 R14: ffff88807fe4ab40 R15: ffff888029210580 [ 417.807801] FS: 00007f339fa7a740(0000) GS:ffff8881fa9b9000(0000) knlGS:0000000000000000 [ 417.808570] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 417.809193] CR2: 0000000000000b00 CR3: 000000002a4f0004 CR4: 0000000000370ef0 [ 417.809925] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 417.810622] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 417.811353] Call Trace: [ 417.811709] <TASK> [ 417.812038] folio_add_file_rmap_ptes+0x143/0x230 [ 417.812566] insert_page_into_pte_locked+0x1ee/0x3c0 [ 417.813132] insert_page+0x78/0xf0 [ 417.813558] vmf_insert_page_mkwrite+0x55/0xa0 [ 417.814088] dax_fault_iter+0x484/0x7b0 [ 417.814542] dax_iomap_pte_fault+0x1ca/0x620 [ 417.815055] dax_iomap_fault+0x39/0x40 [ 417.815499] __xfs_write_fault+0x139/0x380 [ 417.815995] ? __handle_mm_fault+0x5e5/0x1a60 [ 417.816483] xfs_write_fault+0x41/0x50 [ 417.816966] xfs_filemap_fault+0x3b/0xe0 [ 417.817424] __do_fault+0x31/0x180 [ 417.817859] __handle_mm_fault+0xee1/0x1a60 [ 417.818325] ? debug_smp_processor_id+0x17/0x20 [ 417.818844] handle_mm_fault+0xe1/0x2b0 [...] The issue is that when we split a large ZONE_DEVICE folio to order-0 ones, we don't reset the order/_nr_pages. As folio->_nr_pages overlays page[1]->memcg_data, once page[1] is a folio, it suddenly looks like it has folio->memcg_data set. And we never manually initialize folio->memcg_data in fsdax code, because we never expect it to be set at all. When __lruvec_stat_mod_folio() then stumbles over such a folio, it tries to use folio->memcg_data (because it's non-NULL) but it does not actually point at a memcg, resulting in the problem. Alison also observed that these folios sometimes have "locked" set, which is rather concerning (folios locked from the beginning ...). The reason is that the order for large folios is stored in page[1]->flags, which become the folio->flags of a new small folio. Let's fix it by adding a folio helper to clear order/_nr_pages for splitting purposes. Maybe we should reinitialize other large folio flags / folio members as well when splitting, because they might similarly cause harm once page[1] becomes a folio? At least other flags in PAGE_FLAGS_SECOND should not be set for fsdax, so at least page[1]->flags might be as expected with this fix. From a quick glimpse, initializing ->mapping, ->pgmap and ->share should re-initialize most things from a previous page[1] used by large folios that fsdax cares about. For example folio->private might not get reinitialized, but maybe that's not relevant -- no traces of it's use in fsdax code. Needs a closer look. Another thing that should be considered in the future is performing similar checks as we perform in free_tail_page_prepare() -- checking pincount etc. -- when freeing a large fsdax folio. Link: https://lkml.kernel.org/r/20250410091020.119116-1-david@redhat.com Fixes: 4996fc547f5b ("mm: let _folio_nr_pages overlay memcg_data in first tail page") Fixes: 38607c62b34b ("fs/dax: properly refcount fs dax pages") Signed-off-by: David Hildenbrand <david@redhat.com> Reported-by: Alison Schofield <alison.schofield@intel.com> Closes: https://lkml.kernel.org/r/Z_W9Oeg-D9FhImf3@aschofie-mobl2.lan Tested-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Tested-by: "Darrick J. Wong" <djwong@kernel.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Matthew Wilcox <willy@infradead.org> Cc: Alistair Popple <apopple@nvidia.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-04-14page_pool: Track DMA-mapped pages and unmap them when destroying the poolToke Høiland-Jørgensen
When enabling DMA mapping in page_pool, pages are kept DMA mapped until they are released from the pool, to avoid the overhead of re-mapping the pages every time they are used. This causes resource leaks and/or crashes when there are pages still outstanding while the device is torn down, because page_pool will attempt an unmap through a non-existent DMA device on the subsequent page return. To fix this, implement a simple tracking of outstanding DMA-mapped pages in page pool using an xarray. This was first suggested by Mina[0], and turns out to be fairly straight forward: We simply store pointers to pages directly in the xarray with xa_alloc() when they are first DMA mapped, and remove them from the array on unmap. Then, when a page pool is torn down, it can simply walk the xarray and unmap all pages still present there before returning, which also allows us to get rid of the get/put_device() calls in page_pool. Using xa_cmpxchg(), no additional synchronisation is needed, as a page will only ever be unmapped once. To avoid having to walk the entire xarray on unmap to find the page reference, we stash the ID assigned by xa_alloc() into the page structure itself, using the upper bits of the pp_magic field. This requires a couple of defines to avoid conflicting with the POINTER_POISON_DELTA define, but this is all evaluated at compile-time, so does not affect run-time performance. The bitmap calculations in this patch gives the following number of bits for different architectures: - 23 bits on 32-bit architectures - 21 bits on PPC64 (because of the definition of ILLEGAL_POINTER_VALUE) - 32 bits on other 64-bit architectures Stashing a value into the unused bits of pp_magic does have the effect that it can make the value stored there lie outside the unmappable range (as governed by the mmap_min_addr sysctl), for architectures that don't define ILLEGAL_POINTER_VALUE. This means that if one of the pointers that is aliased to the pp_magic field (such as page->lru.next) is dereferenced while the page is owned by page_pool, that could lead to a dereference into userspace, which is a security concern. The risk of this is mitigated by the fact that (a) we always clear pp_magic before releasing a page from page_pool, and (b) this would need a use-after-free bug for struct page, which can have many other risks since page->lru.next is used as a generic list pointer in multiple places in the kernel. As such, with this patch we take the position that this risk is negligible in practice. For more discussion, see[1]. Since all the tracking added in this patch is performed on DMA map/unmap, no additional code is needed in the fast path, meaning the performance overhead of this tracking is negligible there. A micro-benchmark shows that the total overhead of the tracking itself is about 400 ns (39 cycles(tsc) 395.218 ns; sum for both map and unmap[2]). Since this cost is only paid on DMA map and unmap, it seems like an acceptable cost to fix the late unmap issue. Further optimisation can narrow the cases where this cost is paid (for instance by eliding the tracking when DMA map/unmap is a no-op). The extra memory needed to track the pages is neatly encapsulated inside xarray, which uses the 'struct xa_node' structure to track items. This structure is 576 bytes long, with slots for 64 items, meaning that a full node occurs only 9 bytes of overhead per slot it tracks (in practice, it probably won't be this efficient, but in any case it should be an acceptable overhead). [0] https://lore.kernel.org/all/CAHS8izPg7B5DwKfSuzz-iOop_YRbk3Sd6Y4rX7KBG9DcVJcyWg@mail.gmail.com/ [1] https://lore.kernel.org/r/20250320023202.GA25514@openwall.com [2] https://lore.kernel.org/r/ae07144c-9295-4c9d-a400-153bb689fe9e@huawei.com Reported-by: Yonglong Liu <liuyonglong@huawei.com> Closes: https://lore.kernel.org/r/8743264a-9700-4227-a556-5f931c720211@huawei.com Fixes: ff7d6b27f894 ("page_pool: refurbish version of page_pool code") Suggested-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Jesper Dangaard Brouer <hawk@kernel.org> Tested-by: Jesper Dangaard Brouer <hawk@kernel.org> Tested-by: Qiuling Ren <qren@redhat.com> Tested-by: Yuying Ma <yuma@redhat.com> Tested-by: Yonglong Liu <liuyonglong@huawei.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://patch.msgid.link/20250409-page-pool-track-dma-v9-2-6a9ef2e0cba8@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-14page_pool: Move pp_magic check into helper functionsToke Høiland-Jørgensen
Since we are about to stash some more information into the pp_magic field, let's move the magic signature checks into a pair of helper functions so it can be changed in one place. Reviewed-by: Mina Almasry <almasrymina@google.com> Tested-by: Yonglong Liu <liuyonglong@huawei.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://patch.msgid.link/20250409-page-pool-track-dma-v9-1-6a9ef2e0cba8@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-03Merge tag 'mm-stable-2025-04-02-22-07' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - The series "mm: fixes for fallouts from mem_init() cleanup" from Mike Rapoport fixes a couple of issues with the just-merged "arch, mm: reduce code duplication in mem_init()" series - The series "MAINTAINERS: add my isub-entries to MM part." from Mike Rapoport does some maintenance on MAINTAINERS - The series "remove tlb_remove_page_ptdesc()" from Qi Zheng does some cleanup work to the page mapping code - The series "mseal system mappings" from Jeff Xu permits sealing of "system mappings", such as vdso, vvar, vvar_vclock, vectors (arm compat-mode), sigpage (arm compat-mode) - Plus the usual shower of singleton patches * tag 'mm-stable-2025-04-02-22-07' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (31 commits) mseal sysmap: add arch-support txt mseal sysmap: enable s390 selftest: test system mappings are sealed mseal sysmap: update mseal.rst mseal sysmap: uprobe mapping mseal sysmap: enable arm64 mseal sysmap: enable x86-64 mseal sysmap: generic vdso vvar mapping selftests: x86: test_mremap_vdso: skip if vdso is msealed mseal sysmap: kernel config and header change mm: pgtable: remove tlb_remove_page_ptdesc() x86: pgtable: convert to use tlb_remove_ptdesc() riscv: pgtable: unconditionally use tlb_remove_ptdesc() mm: pgtable: convert some architectures to use tlb_remove_ptdesc() mm: pgtable: change pt parameter of tlb_remove_ptdesc() to struct ptdesc* mm: pgtable: make generic tlb_remove_table() use struct ptdesc microblaze/mm: put mm_cmdline_setup() in .init.text section mm/memory_hotplug: fix call folio_test_large with tail page in do_migrate_range MAINTAINERS: mm: add entry for secretmem MAINTAINERS: mm: add entry for numa memblocks and numa emulation ...
2025-04-01Merge tag 'vfio-v6.15-rc1' of https://github.com/awilliam/linux-vfioLinus Torvalds
Pull VFIO updates from Alex Williamson: - Relax IGD support code to match display class device rather than specifically requiring a VGA device (Tomita Moeko) - Accelerate DMA mapping of device MMIO by iterating at PMD and PUD levels to take advantage of huge pfnmap support added in v6.12 (Alex Williamson) - Extend virtio vfio-pci variant driver to include migration support for block devices where enabled by the PF (Yishai Hadas) - Virtualize INTx PIN register for devices where the platform does not route legacy PCI interrupts for the device and the interrupt is reported as IRQ_NOTCONNECTED (Alex Williamson) * tag 'vfio-v6.15-rc1' of https://github.com/awilliam/linux-vfio: vfio/pci: Handle INTx IRQ_NOTCONNECTED vfio/virtio: Enable support for virtio-block live migration vfio/type1: Use mapping page mask for pfnmaps mm: Provide address mask in struct follow_pfnmap_args vfio/type1: Use consistent types for page counts vfio/type1: Use vfio_batch for vaddr_get_pfns() vfio/type1: Convert all vaddr_get_pfns() callers to use vfio_batch vfio/type1: Catch zero from pin_user_pages_remote() vfio/pci: match IGD devices in display controller class
2025-04-01mseal sysmap: kernel config and header changeJeff Xu
Patch series "mseal system mappings", v9. As discussed during mseal() upstream process [1], mseal() protects the VMAs of a given virtual memory range against modifications, such as the read/write (RW) and no-execute (NX) bits. For complete descriptions of memory sealing, please see mseal.rst [2]. The mseal() is useful to mitigate memory corruption issues where a corrupted pointer is passed to a memory management system. For example, such an attacker primitive can break control-flow integrity guarantees since read-only memory that is supposed to be trusted can become writable or .text pages can get remapped. The system mappings are readonly only, memory sealing can protect them from ever changing to writable or unmmap/remapped as different attributes. System mappings such as vdso, vvar, vvar_vclock, vectors (arm compat-mode), sigpage (arm compat-mode), are created by the kernel during program initialization, and could be sealed after creation. Unlike the aforementioned mappings, the uprobe mapping is not established during program startup. However, its lifetime is the same as the process's lifetime [3]. It could be sealed from creation. The vsyscall on x86-64 uses a special address (0xffffffffff600000), which is outside the mm managed range. This means mprotect, munmap, and mremap won't work on the vsyscall. Since sealing doesn't enhance the vsyscall's security, it is skipped in this patch. If we ever seal the vsyscall, it is probably only for decorative purpose, i.e. showing the 'sl' flag in the /proc/pid/smaps. For this patch, it is ignored. It is important to note that the CHECKPOINT_RESTORE feature (CRIU) may alter the system mappings during restore operations. UML(User Mode Linux) and gVisor, rr are also known to change the vdso/vvar mappings. Consequently, this feature cannot be universally enabled across all systems. As such, CONFIG_MSEAL_SYSTEM_MAPPINGS is disabled by default. To support mseal of system mappings, architectures must define CONFIG_ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS and update their special mappings calls to pass mseal flag. Additionally, architectures must confirm they do not unmap/remap system mappings during the process lifetime. The existence of this flag for an architecture implies that it does not require the remapping of thest system mappings during process lifetime, so sealing these mappings is safe from a kernel perspective. This version covers x86-64 and arm64 archiecture as minimum viable feature. While no specific CPU hardware features are required for enable this feature on an archiecture, memory sealing requires a 64-bit kernel. Other architectures can choose whether or not to adopt this feature. Currently, I'm not aware of any instances in the kernel code that actively munmap/mremap a system mapping without a request from userspace. The PPC does call munmap when _install_special_mapping fails for vdso; however, it's uncertain if this will ever fail for PPC - this needs to be investigated by PPC in the future [4]. The UML kernel can add this support when KUnit tests require it [5]. In this version, we've improved the handling of system mapping sealing from previous versions, instead of modifying the _install_special_mapping function itself, which would affect all architectures, we now call _install_special_mapping with a sealing flag only within the specific architecture that requires it. This targeted approach offers two key advantages: 1) It limits the code change's impact to the necessary architectures, and 2) It aligns with the software architecture by keeping the core memory management within the mm layer, while delegating the decision of sealing system mappings to the individual architecture, which is particularly relevant since 32-bit architectures never require sealing. Prior to this patch series, we explored sealing special mappings from userspace using glibc's dynamic linker. This approach revealed several issues: - The PT_LOAD header may report an incorrect length for vdso, (smaller than its actual size). The dynamic linker, which relies on PT_LOAD information to determine mapping size, would then split and partially seal the vdso mapping. Since each architecture has its own vdso/vvar code, fixing this in the kernel would require going through each archiecture. Our initial goal was to enable sealing readonly mappings, e.g. .text, across all architectures, sealing vdso from kernel since creation appears to be simpler than sealing vdso at glibc. - The [vvar] mapping header only contains address information, not length information. Similar issues might exist for other special mappings. - Mappings like uprobe are not covered by the dynamic linker, and there is no effective solution for them. This feature's security enhancements will benefit ChromeOS, Android, and other high security systems. Testing: This feature was tested on ChromeOS and Android for both x86-64 and ARM64. - Enable sealing and verify vdso/vvar, sigpage, vector are sealed properly, i.e. "sl" shown in the smaps for those mappings, and mremap is blocked. - Passing various automation tests (e.g. pre-checkin) on ChromeOS and Android to ensure the sealing doesn't affect the functionality of Chromebook and Android phone. I also tested the feature on Ubuntu on x86-64: - With config disabled, vdso/vvar is not sealed, - with config enabled, vdso/vvar is sealed, and booting up Ubuntu is OK, normal operations such as browsing the web, open/edit doc are OK. Link: https://lore.kernel.org/all/20240415163527.626541-1-jeffxu@chromium.org/ [1] Link: Documentation/userspace-api/mseal.rst [2] Link: https://lore.kernel.org/all/CABi2SkU9BRUnqf70-nksuMCQ+yyiWjo3fM4XkRkL-NrCZxYAyg@mail.gmail.com/ [3] Link: https://lore.kernel.org/all/CABi2SkV6JJwJeviDLsq9N4ONvQ=EFANsiWkgiEOjyT9TQSt+HA@mail.gmail.com/ [4] Link: https://lore.kernel.org/all/202502251035.239B85A93@keescook/ [5] This patch (of 7): Provide infrastructure to mseal system mappings. Establish two kernel configs (CONFIG_MSEAL_SYSTEM_MAPPINGS, ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS) and VM_SEALED_SYSMAP macro for future patches. Link: https://lkml.kernel.org/r/20250305021711.3867874-1-jeffxu@google.com Link: https://lkml.kernel.org/r/20250305021711.3867874-2-jeffxu@google.com Signed-off-by: Jeff Xu <jeffxu@chromium.org> Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org> Cc: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrei Vagin <avagin@gmail.com> Cc: Anna-Maria Behnsen <anna-maria@linutronix.de> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Benjamin Berg <benjamin@sipsolutions.net> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Cc: David S. Miller <davem@davemloft.net> Cc: Elliot Hughes <enh@google.com> Cc: Florian Faineli <f.fainelli@gmail.com> Cc: Greg Ungerer <gerg@kernel.org> Cc: Guenter Roeck <groeck@chromium.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jann Horn <jannh@google.com> Cc: Jason A. Donenfeld <jason@zx2c4.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Jorge Lucangeli Obes <jorgelo@chromium.org> Cc: Linus Waleij <linus.walleij@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcow (Oracle) <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Mike Rapoport <mike.rapoport@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Pedro Falcato <pedro.falcato@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Stephen Röttger <sroettger@google.com> Cc: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-04-01Merge tag 'mm-stable-2025-03-30-16-52' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - The series "Enable strict percpu address space checks" from Uros Bizjak uses x86 named address space qualifiers to provide compile-time checking of percpu area accesses. This has caused a small amount of fallout - two or three issues were reported. In all cases the calling code was found to be incorrect. - The series "Some cleanup for memcg" from Chen Ridong implements some relatively monir cleanups for the memcontrol code. - The series "mm: fixes for device-exclusive entries (hmm)" from David Hildenbrand fixes a boatload of issues which David found then using device-exclusive PTE entries when THP is enabled. More work is needed, but this makes thins better - our own HMM selftests now succeed. - The series "mm: zswap: remove z3fold and zbud" from Yosry Ahmed remove the z3fold and zbud implementations. They have been deprecated for half a year and nobody has complained. - The series "mm: further simplify VMA merge operation" from Lorenzo Stoakes implements numerous simplifications in this area. No runtime effects are anticipated. - The series "mm/madvise: remove redundant mmap_lock operations from process_madvise()" from SeongJae Park rationalizes the locking in the madvise() implementation. Performance gains of 20-25% were observed in one MADV_DONTNEED microbenchmark. - The series "Tiny cleanup and improvements about SWAP code" from Baoquan He contains a number of touchups to issues which Baoquan noticed when working on the swap code. - The series "mm: kmemleak: Usability improvements" from Catalin Marinas implements a couple of improvements to the kmemleak user-visible output. - The series "mm/damon/paddr: fix large folios access and schemes handling" from Usama Arif provides a couple of fixes for DAMON's handling of large folios. - The series "mm/damon/core: fix wrong and/or useless damos_walk() behaviors" from SeongJae Park fixes a few issues with the accuracy of kdamond's walking of DAMON regions. - The series "expose mapping wrprotect, fix fb_defio use" from Lorenzo Stoakes changes the interaction between framebuffer deferred-io and core MM. No functional changes are anticipated - this is preparatory work for the future removal of page structure fields. - The series "mm/damon: add support for hugepage_size DAMOS filter" from Usama Arif adds a DAMOS filter which permits the filtering by huge page sizes. - The series "mm: permit guard regions for file-backed/shmem mappings" from Lorenzo Stoakes extends the guard region feature from its present "anon mappings only" state. The feature now covers shmem and file-backed mappings. - The series "mm: batched unmap lazyfree large folios during reclamation" from Barry Song cleans up and speeds up the unmapping for pte-mapped large folios. - The series "reimplement per-vma lock as a refcount" from Suren Baghdasaryan puts the vm_lock back into the vma. Our reasons for pulling it out were largely bogus and that change made the code more messy. This patchset provides small (0-10%) improvements on one microbenchmark. - The series "Docs/mm/damon: misc DAMOS filters documentation fixes and improves" from SeongJae Park does some maintenance work on the DAMON docs. - The series "hugetlb/CMA improvements for large systems" from Frank van der Linden addresses a pile of issues which have been observed when using CMA on large machines. - The series "mm/damon: introduce DAMOS filter type for unmapped pages" from SeongJae Park enables users of DMAON/DAMOS to filter my the page's mapped/unmapped status. - The series "zsmalloc/zram: there be preemption" from Sergey Senozhatsky teaches zram to run its compression and decompression operations preemptibly. - The series "selftests/mm: Some cleanups from trying to run them" from Brendan Jackman fixes a pile of unrelated issues which Brendan encountered while runnimg our selftests. - The series "fs/proc/task_mmu: add guard region bit to pagemap" from Lorenzo Stoakes permits userspace to use /proc/pid/pagemap to determine whether a particular page is a guard page. - The series "mm, swap: remove swap slot cache" from Kairui Song removes the swap slot cache from the allocation path - it simply wasn't being effective. - The series "mm: cleanups for device-exclusive entries (hmm)" from David Hildenbrand implements a number of unrelated cleanups in this code. - The series "mm: Rework generic PTDUMP configs" from Anshuman Khandual implements a number of preparatoty cleanups to the GENERIC_PTDUMP Kconfig logic. - The series "mm/damon: auto-tune aggregation interval" from SeongJae Park implements a feedback-driven automatic tuning feature for DAMON's aggregation interval tuning. - The series "Fix lazy mmu mode" from Ryan Roberts fixes some issues in powerpc, sparc and x86 lazy MMU implementations. Ryan did this in preparation for implementing lazy mmu mode for arm64 to optimize vmalloc. - The series "mm/page_alloc: Some clarifications for migratetype fallback" from Brendan Jackman reworks some commentary to make the code easier to follow. - The series "page_counter cleanup and size reduction" from Shakeel Butt cleans up the page_counter code and fixes a size increase which we accidentally added late last year. - The series "Add a command line option that enables control of how many threads should be used to allocate huge pages" from Thomas Prescher does that. It allows the careful operator to significantly reduce boot time by tuning the parallalization of huge page initialization. - The series "Fix calculations in trace_balance_dirty_pages() for cgwb" from Tang Yizhou fixes the tracing output from the dirty page balancing code. - The series "mm/damon: make allow filters after reject filters useful and intuitive" from SeongJae Park improves the handling of allow and reject filters. Behaviour is made more consistent and the documention is updated accordingly. - The series "Switch zswap to object read/write APIs" from Yosry Ahmed updates zswap to the new object read/write APIs and thus permits the removal of some legacy code from zpool and zsmalloc. - The series "Some trivial cleanups for shmem" from Baolin Wang does as it claims. - The series "fs/dax: Fix ZONE_DEVICE page reference counts" from Alistair Popple regularizes the weird ZONE_DEVICE page refcount handling in DAX, permittig the removal of a number of special-case checks. - The series "refactor mremap and fix bug" from Lorenzo Stoakes is a preparatoty refactoring and cleanup of the mremap() code. - The series "mm: MM owner tracking for large folios (!hugetlb) + CONFIG_NO_PAGE_MAPCOUNT" from David Hildenbrand reworks the manner in which we determine whether a large folio is known to be mapped exclusively into a single MM. - The series "mm/damon: add sysfs dirs for managing DAMOS filters based on handling layers" from SeongJae Park adds a couple of new sysfs directories to ease the management of DAMON/DAMOS filters. - The series "arch, mm: reduce code duplication in mem_init()" from Mike Rapoport consolidates many per-arch implementations of mem_init() into code generic code, where that is practical. - The series "mm/damon/sysfs: commit parameters online via damon_call()" from SeongJae Park continues the cleaning up of sysfs access to DAMON internal data. - The series "mm: page_ext: Introduce new iteration API" from Luiz Capitulino reworks the page_ext initialization to fix a boot-time crash which was observed with an unusual combination of compile and cmdline options. - The series "Buddy allocator like (or non-uniform) folio split" from Zi Yan reworks the code to split a folio into smaller folios. The main benefit is lessened memory consumption: fewer post-split folios are generated. - The series "Minimize xa_node allocation during xarry split" from Zi Yan reduces the number of xarray xa_nodes which are generated during an xarray split. - The series "drivers/base/memory: Two cleanups" from Gavin Shan performs some maintenance work on the drivers/base/memory code. - The series "Add tracepoints for lowmem reserves, watermarks and totalreserve_pages" from Martin Liu adds some more tracepoints to the page allocator code. - The series "mm/madvise: cleanup requests validations and classifications" from SeongJae Park cleans up some warts which SeongJae observed during his earlier madvise work. - The series "mm/hwpoison: Fix regressions in memory failure handling" from Shuai Xue addresses two quite serious regressions which Shuai has observed in the memory-failure implementation. - The series "mm: reliable huge page allocator" from Johannes Weiner makes huge page allocations cheaper and more reliable by reducing fragmentation. - The series "Minor memcg cleanups & prep for memdescs" from Matthew Wilcox is preparatory work for the future implementation of memdescs. - The series "track memory used by balloon drivers" from Nico Pache introduces a way to track memory used by our various balloon drivers. - The series "mm/damon: introduce DAMOS filter type for active pages" from Nhat Pham permits users to filter for active/inactive pages, separately for file and anon pages. - The series "Adding Proactive Memory Reclaim Statistics" from Hao Jia separates the proactive reclaim statistics from the direct reclaim statistics. - The series "mm/vmscan: don't try to reclaim hwpoison folio" from Jinjiang Tu fixes our handling of hwpoisoned pages within the reclaim code. * tag 'mm-stable-2025-03-30-16-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (431 commits) mm/page_alloc: remove unnecessary __maybe_unused in order_to_pindex() x86/mm: restore early initialization of high_memory for 32-bits mm/vmscan: don't try to reclaim hwpoison folio mm/hwpoison: introduce folio_contain_hwpoisoned_page() helper cgroup: docs: add pswpin and pswpout items in cgroup v2 doc mm: vmscan: split proactive reclaim statistics from direct reclaim statistics selftests/mm: speed up split_huge_page_test selftests/mm: uffd-unit-tests support for hugepages > 2M docs/mm/damon/design: document active DAMOS filter type mm/damon: implement a new DAMOS filter type for active pages fs/dax: don't disassociate zero page entries MM documentation: add "Unaccepted" meminfo entry selftests/mm: add commentary about 9pfs bugs fork: use __vmalloc_node() for stack allocation docs/mm: Physical Memory: Populate the "Zones" section xen: balloon: update the NR_BALLOON_PAGES state hv_balloon: update the NR_BALLOON_PAGES state balloon_compaction: update the NR_BALLOON_PAGES state meminfo: add a per node counter for balloon drivers mm: remove references to folio in __memcg_kmem_uncharge_page() ...
2025-03-31Merge tag 'trace-ringbuffer-v6.15-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull ring-buffer updates from Steven Rostedt: - Restructure the persistent memory to have a "scratch" area Instead of hard coding the KASLR offset in the persistent memory by the ring buffer, push that work up to the callers of the persistent memory as they are the ones that need this information. The offsets and such is not important to the ring buffer logic and it should not be part of that. A scratch pad is now created when the caller allocates a ring buffer from persistent memory by stating how much memory it needs to save. - Allow where modules are loaded to be saved in the new scratch pad Save the addresses of modules when they are loaded into the persistent memory scratch pad. - A new module_for_each_mod() helper function was created With the acknowledgement of the module maintainers a new module helper function was created to iterate over all the currently loaded modules. This has a callback to be called for each module. This is needed for when tracing is started in the persistent buffer and the currently loaded modules need to be saved in the scratch area. - Expose the last boot information where the kernel and modules were loaded The last_boot_info file is updated to print out the addresses of where the kernel "_text" location was loaded from a previous boot, as well as where the modules are loaded. If the buffer is recording the current boot, it only prints "# Current" so that it does not expose the KASLR offset of the currently running kernel. - Allow the persistent ring buffer to be released (freed) To have this in production environments, where the kernel command line can not be changed easily, the ring buffer needs to be freed when it is not going to be used. The memory for the buffer will always be allocated at boot up, but if the system isn't going to enable tracing, the memory needs to be freed. Allow it to be freed and added back to the kernel memory pool. - Allow stack traces to print the function names in the persistent buffer Now that the modules are saved in the persistent ring buffer, if the same modules are loaded, the printing of the function names will examine the saved modules. If the module is found in the scratch area and is also loaded, then it will do the offset shift and use kallsyms to display the function name. If the address is not found, it simply displays the address from the previous boot in hex. * tag 'trace-ringbuffer-v6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Use _text and the kernel offset in last_boot_info tracing: Show last module text symbols in the stacktrace ring-buffer: Remove the unused variable bmeta tracing: Skip update_last_data() if cleared and remove active check for save_mod() tracing: Initialize scratch_size to zero to prevent UB tracing: Fix a compilation error without CONFIG_MODULES tracing: Freeable reserved ring buffer mm/memblock: Add reserved memory release function tracing: Update modules to persistent instances when loaded tracing: Show module names and addresses of last boot tracing: Have persistent trace instances save module addresses module: Add module_for_each_mod() function tracing: Have persistent trace instances save KASLR offset ring-buffer: Add ring_buffer_meta_scratch() ring-buffer: Add buffer meta data for persistent ring buffer ring-buffer: Use kaslr address instead of text delta ring-buffer: Fix bytes_dropped calculation issue
2025-03-30Merge tag 'bpf-next-6.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Pull bpf updates from Alexei Starovoitov: "For this merge window we're splitting BPF pull request into three for higher visibility: main changes, res_spin_lock, try_alloc_pages. These are the main BPF changes: - Add DFA-based live registers analysis to improve verification of programs with loops (Eduard Zingerman) - Introduce load_acquire and store_release BPF instructions and add x86, arm64 JIT support (Peilin Ye) - Fix loop detection logic in the verifier (Eduard Zingerman) - Drop unnecesary lock in bpf_map_inc_not_zero() (Eric Dumazet) - Add kfunc for populating cpumask bits (Emil Tsalapatis) - Convert various shell based tests to selftests/bpf/test_progs format (Bastien Curutchet) - Allow passing referenced kptrs into struct_ops callbacks (Amery Hung) - Add a flag to LSM bpf hook to facilitate bpf program signing (Blaise Boscaccy) - Track arena arguments in kfuncs (Ihor Solodrai) - Add copy_remote_vm_str() helper for reading strings from remote VM and bpf_copy_from_user_task_str() kfunc (Jordan Rome) - Add support for timed may_goto instruction (Kumar Kartikeya Dwivedi) - Allow bpf_get_netns_cookie() int cgroup_skb programs (Mahe Tardy) - Reduce bpf_cgrp_storage_busy false positives when accessing cgroup local storage (Martin KaFai Lau) - Introduce bpf_dynptr_copy() kfunc (Mykyta Yatsenko) - Allow retrieving BTF data with BTF token (Mykyta Yatsenko) - Add BPF kfuncs to set and get xattrs with 'security.bpf.' prefix (Song Liu) - Reject attaching programs to noreturn functions (Yafang Shao) - Introduce pre-order traversal of cgroup bpf programs (Yonghong Song)" * tag 'bpf-next-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (186 commits) selftests/bpf: Add selftests for load-acquire/store-release when register number is invalid bpf: Fix out-of-bounds read in check_atomic_load/store() libbpf: Add namespace for errstr making it libbpf_errstr bpf: Add struct_ops context information to struct bpf_prog_aux selftests/bpf: Sanitize pointer prior fclose() selftests/bpf: Migrate test_xdp_vlan.sh into test_progs selftests/bpf: test_xdp_vlan: Rename BPF sections bpf: clarify a misleading verifier error message selftests/bpf: Add selftest for attaching fexit to __noreturn functions bpf: Reject attaching fexit/fmod_ret to __noreturn functions bpf: Only fails the busy counter check in bpf_cgrp_storage_get if it creates storage bpf: Make perf_event_read_output accessible in all program types. bpftool: Using the right format specifiers bpftool: Add -Wformat-signedness flag to detect format errors selftests/bpf: Test freplace from user namespace libbpf: Pass BPF token from find_prog_btf_id to BPF_BTF_GET_FD_BY_ID bpf: Return prog btf_id without capable check bpf: BPF token support for BPF_BTF_GET_FD_BY_ID bpf, x86: Fix objtool warning for timed may_goto bpf: Check map->record at the beginning of check_and_free_fields() ...
2025-03-28mm/memblock: Add reserved memory release functionMasami Hiramatsu (Google)
Add reserve_mem_release_by_name() to release a reserved memory region with a given name. This allows us to release reserved memory which is defined by kernel cmdline, after boot. Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: linux-mm@kvack.org Link: https://lore.kernel.org/173989133862.230693.14094993331347437600.stgit@devnote2 Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-03-26Merge tag 'sysctl-6.15-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl Pull sysctl updates from Joel Granados: - Move vm_table members out of kernel/sysctl.c All vm_table array members have moved to their respective subsystems leading to the removal of vm_table from kernel/sysctl.c. This increases modularity by placing the ctl_tables closer to where they are actually used and at the same time reducing the chances of merge conflicts in kernel/sysctl.c. - ctl_table range fixes Replace the proc_handler function that checks variable ranges in coredump_sysctls and vdso_table with the one that actually uses the extra{1,2} pointers as min/max values. This tightens the range of the values that users can pass into the kernel effectively preventing {under,over}flows. - Misc fixes Correct grammar errors and typos in test messages. Update sysctl files in MAINTAINERS. Constified and removed array size in declaration for alignment_tbl * tag 'sysctl-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl: (22 commits) selftests/sysctl: fix wording of help messages selftests: fix spelling/grammar errors in sysctl/sysctl.sh MAINTAINERS: Update sysctl file list in MAINTAINERS sysctl: Fix underflow value setting risk in vm_table coredump: Fixes core_pipe_limit sysctl proc_handler sysctl: remove unneeded include sysctl: remove the vm_table sh: vdso: move the sysctl to arch/sh/kernel/vsyscall/vsyscall.c x86: vdso: move the sysctl to arch/x86/entry/vdso/vdso32-setup.c fs: dcache: move the sysctl to fs/dcache.c sunrpc: simplify rpcauth_cache_shrink_count() fs: drop_caches: move sysctl to fs/drop_caches.c fs: fs-writeback: move sysctl to fs/fs-writeback.c mm: nommu: move sysctl to mm/nommu.c security: min_addr: move sysctl to security/min_addr.c mm: mmap: move sysctl to mm/mmap.c mm: util: move sysctls to mm/util.c mm: vmscan: move vmscan sysctls to mm/vmscan.c mm: swap: move sysctl to mm/swap.c mm: filemap: move sysctl to mm/filemap.c ...