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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
...
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"The headline feature is the re-enablement of support for Arm's
Scalable Matrix Extension (SME) thanks to a bumper crop of fixes
from Mark Rutland.
If matrices aren't your thing, then Ryan's page-table optimisation
work is much more interesting.
Summary:
ACPI, EFI and PSCI:
- Decouple Arm's "Software Delegated Exception Interface" (SDEI)
support from the ACPI GHES code so that it can be used by platforms
booted with device-tree
- Remove unnecessary per-CPU tracking of the FPSIMD state across EFI
runtime calls
- Fix a node refcount imbalance in the PSCI device-tree code
CPU Features:
- Ensure register sanitisation is applied to fields in ID_AA64MMFR4
- Expose AIDR_EL1 to userspace via sysfs, primarily so that KVM
guests can reliably query the underlying CPU types from the VMM
- Re-enabling of SME support (CONFIG_ARM64_SME) as a result of fixes
to our context-switching, signal handling and ptrace code
Entry code:
- Hook up TIF_NEED_RESCHED_LAZY so that CONFIG_PREEMPT_LAZY can be
selected
Memory management:
- Prevent BSS exports from being used by the early PI code
- Propagate level and stride information to the low-level TLB
invalidation routines when operating on hugetlb entries
- Use the page-table contiguous hint for vmap() mappings with
VM_ALLOW_HUGE_VMAP where possible
- Optimise vmalloc()/vmap() page-table updates to use "lazy MMU mode"
and hook this up on arm64 so that the trailing DSB (used to publish
the updates to the hardware walker) can be deferred until the end
of the mapping operation
- Extend mmap() randomisation for 52-bit virtual addresses (on par
with 48-bit addressing) and remove limited support for
randomisation of the linear map
Perf and PMUs:
- Add support for probing the CMN-S3 driver using ACPI
- Minor driver fixes to the CMN, Arm-NI and amlogic PMU drivers
Selftests:
- Fix FPSIMD and SME tests to align with the freshly re-enabled SME
support
- Fix default setting of the OUTPUT variable so that tests are
installed in the right location
vDSO:
- Replace raw counter access from inline assembly code with a call to
the the __arch_counter_get_cntvct() helper function
Miscellaneous:
- Add some missing header inclusions to the CCA headers
- Rework rendering of /proc/cpuinfo to follow the x86-approach and
avoid repeated buffer expansion (the user-visible format remains
identical)
- Remove redundant selection of CONFIG_CRC32
- Extend early error message when failing to map the device-tree
blob"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (83 commits)
arm64: cputype: Add cputype definition for HIP12
arm64: el2_setup.h: Make __init_el2_fgt labels consistent, again
perf/arm-cmn: Add CMN S3 ACPI binding
arm64/boot: Disallow BSS exports to startup code
arm64/boot: Move global CPU override variables out of BSS
arm64/boot: Move init_pgdir[] and init_idmap_pgdir[] into __pi_ namespace
perf/arm-cmn: Initialise cmn->cpu earlier
kselftest/arm64: Set default OUTPUT path when undefined
arm64: Update comment regarding values in __boot_cpu_mode
arm64: mm: Drop redundant check in pmd_trans_huge()
arm64/mm: Re-organise setting up FEAT_S1PIE registers PIRE0_EL1 and PIR_EL1
arm64/mm: Permit lazy_mmu_mode to be nested
arm64/mm: Disable barrier batching in interrupt contexts
arm64/cpuinfo: only show one cpu's info in c_show()
arm64/mm: Batch barriers when updating kernel mappings
mm/vmalloc: Enter lazy mmu mode while manipulating vmalloc ptes
arm64/mm: Support huge pte-mapped pages in vmap
mm/vmalloc: Gracefully unmap huge ptes
mm/vmalloc: Warn on improper use of vunmap_range()
arm64/mm: Hoist barriers out of set_ptes_anysz() loop
...
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
"Futexes:
- Add support for task local hash maps (Sebastian Andrzej Siewior,
Peter Zijlstra)
- Implement the FUTEX2_NUMA ABI, which feature extends the futex
interface to be NUMA-aware. On NUMA-aware futexes a second u32 word
containing the NUMA node is added to after the u32 futex value word
(Peter Zijlstra)
- Implement the FUTEX2_MPOL ABI, which feature extends the futex
interface to be mempolicy-aware as well, to further refine futex
node mappings and lookups (Peter Zijlstra)
Locking primitives:
- Misc cleanups (Andy Shevchenko, Borislav Petkov, Colin Ian King,
Ingo Molnar, Nam Cao, Peter Zijlstra)
Lockdep:
- Prevent abuse of lockdep subclasses (Waiman Long)
- Add number of dynamic keys to /proc/lockdep_stats (Waiman Long)
Plus misc cleanups and fixes"
* tag 'locking-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits)
selftests/futex: Fix spelling mistake "unitiliazed" -> "uninitialized"
futex: Correct the kernedoc return value for futex_wait_setup().
tools headers: Synchronize prctl.h ABI header
futex: Use RCU_INIT_POINTER() in futex_mm_init().
selftests/futex: Use TAP output in futex_numa_mpol
selftests/futex: Use TAP output in futex_priv_hash
futex: Fix kernel-doc comments
futex: Relax the rcu_assign_pointer() assignment of mm->futex_phash in futex_mm_init()
futex: Fix outdated comment in struct restart_block
locking/lockdep: Add number of dynamic keys to /proc/lockdep_stats
locking/lockdep: Prevent abuse of lockdep subclass
locking/lockdep: Move hlock_equal() to the respective #ifdeffery
futex,selftests: Add another FUTEX2_NUMA selftest
selftests/futex: Add futex_numa_mpol
selftests/futex: Add futex_priv_hash
selftests/futex: Build without headers nonsense
tools/perf: Allow to select the number of hash buckets
tools headers: Synchronize prctl.h ABI header
futex: Implement FUTEX2_MPOL
futex: Implement FUTEX2_NUMA
...
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The common case is to grow reallocations, and since init_on_alloc will
have already zeroed the whole allocation, we only need to zero when
shrinking the allocation.
Link: https://lkml.kernel.org/r/20250515214217.619685-2-kees@kernel.org
Fixes: a0309faf1cb0 ("mm: vmalloc: support more granular vrealloc() sizing")
Signed-off-by: Kees Cook <kees@kernel.org>
Tested-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: "Erhard F." <erhard_f@mailbox.org>
Cc: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Patch series "mm: vmalloc: Actually use the in-place vrealloc region".
This fixes a performance regression[1] with vrealloc()[1].
The refactoring to not build a new vmalloc region only actually worked
when shrinking. Actually return the resized area when it grows. Ugh.
Link: https://lkml.kernel.org/r/20250515214217.619685-1-kees@kernel.org
Fixes: a0309faf1cb0 ("mm: vmalloc: support more granular vrealloc() sizing")
Signed-off-by: Kees Cook <kees@kernel.org>
Reported-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Closes: https://lore.kernel.org/all/20250515-bpf-verifier-slowdown-vwo2meju4cgp2su5ckj@6gi6ssxbnfqg [1]
Tested-by: Eduard Zingerman <eddyz87@gmail.com>
Tested-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Tested-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Cc: "Erhard F." <erhard_f@mailbox.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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The following data-race was found in show_numa_info():
==================================================================
BUG: KCSAN: data-race in vmalloc_info_show / vmalloc_info_show
read to 0xffff88800971fe30 of 4 bytes by task 8289 on cpu 0:
show_numa_info mm/vmalloc.c:4936 [inline]
vmalloc_info_show+0x5a8/0x7e0 mm/vmalloc.c:5016
seq_read_iter+0x373/0xb40 fs/seq_file.c:230
proc_reg_read_iter+0x11e/0x170 fs/proc/inode.c:299
....
write to 0xffff88800971fe30 of 4 bytes by task 8287 on cpu 1:
show_numa_info mm/vmalloc.c:4934 [inline]
vmalloc_info_show+0x38f/0x7e0 mm/vmalloc.c:5016
seq_read_iter+0x373/0xb40 fs/seq_file.c:230
proc_reg_read_iter+0x11e/0x170 fs/proc/inode.c:299
....
value changed: 0x0000008f -> 0x00000000
==================================================================
According to this report,there is a read/write data-race because
m->private is accessible to multiple CPUs. To fix this, instead of
allocating the heap in proc_vmalloc_init() and passing the heap address to
m->private, vmalloc_info_show() should allocate the heap.
Link: https://lkml.kernel.org/r/20250508165620.15321-1-aha310510@gmail.com
Fixes: 8e1d743f2c26 ("mm: vmalloc: support multiple nodes in vmallocinfo")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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In codes of alloc_vmap_area(), it returns the upper bound 'vend' to
indicate if the allocation is successful or failed. That is not very
clear.
Here change to return explicit error values and check them to judge if
allocation is successful.
Link: https://lkml.kernel.org/r/20250418223653.243436-6-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Shivank Garg <shivankg@amd.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Remove unneeded local variables and replace them with values.
Link: https://lkml.kernel.org/r/20250418223653.243436-5-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Shivank Garg <shivankg@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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When purge lazily freed vmap areas, VA stored in vn->pool[] will also be
taken away into free vmap tree partially or completely accordingly, that
is done in decay_va_pool_node(). When doing that, for each pool of node,
the whole list is detached from the pool for handling. At this time, that
pool is empty. It's not necessary to update the pool size each time when
one VA is removed and addded into free vmap tree.
Here change code to update the pool size when attaching the pool back.
Link: https://lkml.kernel.org/r/20250418223653.243436-4-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Shivank Garg <shivankg@amd.com>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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When finding VA in vn->busy, if VA spans several zones and the passed addr
is not the same as va->va_start, we should scan the vn in reverse odrdr
because the starting address of VA must be smaller than the passed addr if
it really resides in the VA.
E.g on a system nr_vmap_nodes=100,
<----va---->
-|-----|-----|-----|-----|-----|-----|-----|-----|-----|-
... n-1 n n+1 n+2 ... 100 0 1
VA resides in node 'n' whereas it spans 'n', 'n+1' and 'n+2'. If passed
addr is within 'n+2', we should try nodes backwards on 'n+1' and 'n', then
succeed very soon.
Meanwhile we still need loop around because VA could spans node from 'n'
to node 100, node 0, node 1.
Anyway, changing to find in reverse order can improve efficiency on many
CPUs system.
Link: https://lkml.kernel.org/r/20250418223653.243436-3-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Shivank Garg <shivankg@amd.com>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Patch series "mm/vmalloc.c: code cleanup and improvements", v2.
These changes were made from code inspection in mm/vmalloc.c.
This patch (of 5):
Static variable 'purge_ndoes' is defined in global scope, while it's only
used in function __purge_vmap_area_lazy(). It mainly serves to avoid
memory allocation repeatedly, especially when NR_CPUS is big.
While a local static variable can also satisfy the demand, and can improve
code readibility. Hence move its definition into
__purge_vmap_area_lazy().
Link: https://lkml.kernel.org/r/20250418223653.243436-1-bhe@redhat.com
Link: https://lkml.kernel.org/r/20250418223653.243436-2-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Shivank Garg <shivankg@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Currently both atomics share one cache-line:
<snip>
...
ffffffff83eab400 b vmap_lazy_nr
ffffffff83eab408 b nr_vmalloc_pages
...
<snip>
those are global variables and they are only 8 bytes apart. Since they
are modified by different threads this causes a false sharing. This can
lead to a performance drop due to unnecessary cache invalidations.
After this patch it is aligned to a cache line boundary:
<snip>
...
ffffffff8260a600 d vmap_lazy_nr
ffffffff8260a640 d nr_vmalloc_pages
...
<snip>
Link: https://lkml.kernel.org/r/20250417161216.88318-4-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Adrian Huang <ahuang12@lenovo.com>
Tested-by: Adrian Huang <ahuang12@lenovo.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Christop Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Switch from the atomic_long_add_return() to its relaxed version.
We do not need a full memory barrier or any memory ordering during
increasing the "vmap_lazy_nr" variable. What we only need is to do it
atomically. This is what atomic_long_add_return_relaxed() guarantees.
AARCH64:
<snip>
Default:
40ec: d34cfe94 lsr x20, x20, #12
40f0: 14000044 b 4200 <free_vmap_area_noflush+0x19c>
40f4: 94000000 bl 0 <__sanitizer_cov_trace_pc>
40f8: 90000000 adrp x0, 0 <__traceiter_alloc_vmap_area>
40fc: 91000000 add x0, x0, #0x0
4100: f8f40016 ldaddal x20, x22, [x0]
4104: 8b160296 add x22, x20, x22
Relaxed:
40ec: d34cfe94 lsr x20, x20, #12
40f0: 14000044 b 4200 <free_vmap_area_noflush+0x19c>
40f4: 94000000 bl 0 <__sanitizer_cov_trace_pc>
40f8: 90000000 adrp x0, 0 <__traceiter_alloc_vmap_area>
40fc: 91000000 add x0, x0, #0x0
4100: f8340016 ldadd x20, x22, [x0]
4104: 8b160296 add x22, x20, x22
<snip>
Link: https://lkml.kernel.org/r/20250415112646.113091-1-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Christop Hellwig <hch@infradead.org>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Update a __purge_vmap_area_lazy() to use introduced helper. This is last
place in vmalloc code. Also this patch introduces an extra function which
is node_to_id() that converts a vmap_node pointer to an index in array.
__purge_vmap_area_lazy() requires that extra function.
Link: https://lkml.kernel.org/r/20250408151549.77937-3-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christop Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
There are places which can be updated easily to use the helper to iterate
over all vmap-nodes. This is what this patch does.
The aim is to improve readability and simplify the code.
[akpm@linux-foundation.org: fix build warning]
Link: https://lkml.kernel.org/r/20250408151549.77937-2-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christop Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
To simplify iteration over vmap-nodes, add the for_each_vmap_node() macro
that iterates over all nodes in a system. It tends to simplify the code.
Link: https://lkml.kernel.org/r/20250408151549.77937-1-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christop Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The vmalloc region can either be charged to a single memcg or none. At
the moment kernel traverses all the pages backing the vmalloc region to
update the MEMCG_VMALLOC stat. However there is no need to look at all
the pages as all those pages will be charged to a single memcg or none.
Simplify the MEMCG_VMALLOC update by just looking at the first page of the
vmalloc region.
[shakeel.butt@linux.dev: add comment]
Link: https://lkml.kernel.org/r/bmlkdbqgwboyqrnxyom7n52fjmo76ux77jhqw5odc6c6dfon3h@zdylwtmlywbt
Link: https://lkml.kernel.org/r/20250403053326.26860-1-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Wrap vmalloc's pte table manipulation loops with
arch_enter_lazy_mmu_mode() / arch_leave_lazy_mmu_mode(). This provides
the arch code with the opportunity to optimize the pte manipulations.
Note that vmap_pfn() already uses lazy mmu mode since it delegates to
apply_to_page_range() which enters lazy mmu mode for both user and
kernel mappings.
These hooks will shortly be used by arm64 to improve vmalloc
performance.
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Tested-by: Luiz Capitulino <luizcap@redhat.com>
Link: https://lore.kernel.org/r/20250422081822.1836315-11-ryan.roberts@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Commit f7ee1f13d606 ("mm/vmalloc: enable mapping of huge pages at pte
level in vmap") added its support by reusing the set_huge_pte_at() API,
which is otherwise only used for user mappings. But when unmapping those
huge ptes, it continued to call ptep_get_and_clear(), which is a
layering violation. To date, the only arch to implement this support is
powerpc and it all happens to work ok for it.
But arm64's implementation of ptep_get_and_clear() can not be safely
used to clear a previous set_huge_pte_at(). So let's introduce a new
arch opt-in function, arch_vmap_pte_range_unmap_size(), which can
provide the size of a (present) pte. Then we can call
huge_ptep_get_and_clear() to tear it down properly.
Note that if vunmap_range() is called with a range that starts in the
middle of a huge pte-mapped page, we must unmap the entire huge page so
the behaviour is consistent with pmd and pud block mappings. In this
case emit a warning just like we do for pmd/pud mappings.
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Tested-by: Luiz Capitulino <luizcap@redhat.com>
Link: https://lore.kernel.org/r/20250422081822.1836315-9-ryan.roberts@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
|
|
A call to vmalloc_huge() may cause memory blocks to be mapped at pmd or
pud level. But it is possible to subsequently call vunmap_range() on a
sub-range of the mapped memory, which partially overlaps a pmd or pud.
In this case, vmalloc unmaps the entire pmd or pud so that the
no-overlapping portion is also unmapped. Clearly that would have a bad
outcome, but it's not something that any callers do today as far as I
can tell. So I guess it's just expected that callers will not do this.
However, it would be useful to know if this happened in future; let's
add a warning to cover the eventuality.
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Tested-by: Luiz Capitulino <luizcap@redhat.com>
Link: https://lore.kernel.org/r/20250422081822.1836315-8-ryan.roberts@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Introduce struct vm_struct::requested_size so that the requested
(re)allocation size is retained separately from the allocated area size.
This means that KASAN will correctly poison the correct spans of requested
bytes. This also means we can support growing the usable portion of an
allocation that can already be supported by the existing area's existing
allocation.
Link: https://lkml.kernel.org/r/20250426001105.it.679-kees@kernel.org
Fixes: 3ddc2fefe6f3 ("mm: vmalloc: implement vrealloc()")
Signed-off-by: Kees Cook <kees@kernel.org>
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Closes: https://lore.kernel.org/all/20250408192503.6149a816@outsider.home/
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
To enable node specific hash-tables using huge pages if possible.
[bigeasy: use __vmalloc_node_range_noprof(), add nommu bits, inline
vmalloc_huge]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250416162921.513656-3-bigeasy@linutronix.de
|
|
According to the code logic, the first parameter of the sub-function
__get_vm_area_node() should be size instead of real_size.
Then in __get_vm_area_node(), the size will be aligned, so the redundant
alignment operation is deleted.
The use of the real_size variable causes code redundancy, so it is removed
to simplify the code.
The real prefix is generally used to indicate the adjusted value of a
parameter, but according to the code logic, it should indicate the
original value, so it is recommended to rename it to original_align.
Link: https://lkml.kernel.org/r/20250306072131.800499-1-liuye@kylinos.cn
Signed-off-by: Liu Ye <liuye@kylinos.cn>
Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: Christop Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Fix callers that previously skipped calling arch_sync_kernel_mappings() if
an error occurred during a pgtable update. The call is still required to
sync any pgtable updates that may have occurred prior to hitting the error
condition.
These are theoretical bugs discovered during code review.
Link: https://lkml.kernel.org/r/20250226121610.2401743-1-ryan.roberts@arm.com
Fixes: 2ba3e6947aed ("mm/vmalloc: track which page-table levels were modified")
Fixes: 0c95cba49255 ("mm: apply_to_pte_range warn and fail if a large pte is encountered")
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christop Hellwig <hch@infradead.org>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The previous commit removed the page_list argument from
alloc_pages_bulk_noprof() along with the alloc_pages_bulk_list() function.
Now that only the *_array() flavour of the API remains, we can do the
following renaming (along with the _noprof() ones):
alloc_pages_bulk_array -> alloc_pages_bulk
alloc_pages_bulk_array_mempolicy -> alloc_pages_bulk_mempolicy
alloc_pages_bulk_array_node -> alloc_pages_bulk_node
Link: https://lkml.kernel.org/r/275a3bbc0be20fbe9002297d60045e67ab3d4ada.1734991165.git.luizcap@redhat.com
Signed-off-by: Luiz Capitulino <luizcap@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
If the caller of vmap() specifies VM_MAP_PUT_PAGES (currently only the
i915 driver), we will decrement nr_vmalloc_pages and MEMCG_VMALLOC in
vfree(). These counters are incremented by vmalloc() but not by vmap() so
this will cause an underflow. Check the VM_MAP_PUT_PAGES flag before
decrementing either counter.
Link: https://lkml.kernel.org/r/20241211202538.168311-1-willy@infradead.org
Fixes: b944afc9d64d ("mm: add a VM_MAP_PUT_PAGES flag for vmap")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Balbir Singh <balbirs@nvidia.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
When vrealloc() reuses already allocated vmap_area, we need to re-annotate
poisoned and unpoisoned portions of underlying memory according to the new
size.
This results in a KASAN splat recorded at [1]. A KASAN mis-reporting
issue where there is none.
Note, hard-coding KASAN_VMALLOC_PROT_NORMAL might not be exactly correct,
but KASAN flag logic is pretty involved and spread out throughout
__vmalloc_node_range_noprof(), so I'm using the bare minimum flag here and
leaving the rest to mm people to refactor this logic and reuse it here.
Link: https://lkml.kernel.org/r/20241126005206.3457974-1-andrii@kernel.org
Link: https://lore.kernel.org/bpf/67450f9b.050a0220.21d33d.0004.GAE@google.com/ [1]
Fixes: 3ddc2fefe6f3 ("mm: vmalloc: implement vrealloc()")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The memory reserved for module tags does not need to be backed by physical
pages until there are tags to store there. Change the way we reserve this
memory to allocate only virtual area for the tags and populate it with
physical pages as needed when we load a module.
[surenb@google.com: avoid execmem_vmap() when !MMU]
Link: https://lkml.kernel.org/r/20241031233611.3833002-1-surenb@google.com
Link: https://lkml.kernel.org/r/20241023170759.999909-5-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Daniel Gomez <da.gomez@samsung.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Minchan Kim <minchan@google.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Petr Pavlu <petr.pavlu@suse.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Sourav Panda <souravpanda@google.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Huth <thuth@redhat.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xiongwei Song <xiongwei.song@windriver.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Using large pages to map text areas reduces iTLB pressure and improves
performance.
Extend execmem_alloc() with an ability to use huge pages with ROX
permissions as a cache for smaller allocations.
To populate the cache, a writable large page is allocated from vmalloc
with VM_ALLOW_HUGE_VMAP, filled with invalid instructions and then
remapped as ROX.
The direct map alias of that large page is exculded from the direct map.
Portions of that large page are handed out to execmem_alloc() callers
without any changes to the permissions.
When the memory is freed with execmem_free() it is invalidated again so
that it won't contain stale instructions.
An architecture has to implement execmem_fill_trapping_insns() callback
and select ARCH_HAS_EXECMEM_ROX configuration option to be able to use the
ROX cache.
The cache is enabled on per-range basis when an architecture sets
EXECMEM_ROX_CACHE flag in definition of an execmem_range.
Link: https://lkml.kernel.org/r/20241023162711.2579610-8-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Tested-by: kdevops <kdevops@lists.linux.dev>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Song Liu <song@kernel.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
vmalloc allocations with VM_ALLOW_HUGE_VMAP that do not explicitly specify
node ID will use huge pages only if size_per_node is larger than a huge
page.
Still the actual allocated memory is not distributed between nodes and
there is no advantage in such approach. On the contrary, BPF allocates
SZ_2M * num_possible_nodes() for each new bpf_prog_pack, while it could do
with a single huge page per pack.
Don't account for number of nodes for VM_ALLOW_HUGE_VMAP with NUMA_NO_NODE
and use huge pages whenever the requested allocation size is larger than a
huge page.
Link: https://lkml.kernel.org/r/20241023162711.2579610-3-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Tested-by: kdevops <kdevops@lists.linux.dev>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Song Liu <song@kernel.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
into one operation
When compiling kernel source 'make -j $(nproc)' with the up-and-running
KASAN-enabled kernel on a 256-core machine, the following soft lockup is
shown:
watchdog: BUG: soft lockup - CPU#28 stuck for 22s! [kworker/28:1:1760]
CPU: 28 PID: 1760 Comm: kworker/28:1 Kdump: loaded Not tainted 6.10.0-rc5 #95
Workqueue: events drain_vmap_area_work
RIP: 0010:smp_call_function_many_cond+0x1d8/0xbb0
Code: 38 c8 7c 08 84 c9 0f 85 49 08 00 00 8b 45 08 a8 01 74 2e 48 89 f1 49 89 f7 48 c1 e9 03 41 83 e7 07 4c 01 e9 41 83 c7 03 f3 90 <0f> b6 01 41 38 c7 7c 08 84 c0 0f 85 d4 06 00 00 8b 45 08 a8 01 75
RSP: 0018:ffffc9000cb3fb60 EFLAGS: 00000202
RAX: 0000000000000011 RBX: ffff8883bc4469c0 RCX: ffffed10776e9949
RDX: 0000000000000002 RSI: ffff8883bb74ca48 RDI: ffffffff8434dc50
RBP: ffff8883bb74ca40 R08: ffff888103585dc0 R09: ffff8884533a1800
R10: 0000000000000004 R11: ffffffffffffffff R12: ffffed1077888d39
R13: dffffc0000000000 R14: ffffed1077888d38 R15: 0000000000000003
FS: 0000000000000000(0000) GS:ffff8883bc400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005577b5c8d158 CR3: 0000000004850000 CR4: 0000000000350ef0
Call Trace:
<IRQ>
? watchdog_timer_fn+0x2cd/0x390
? __pfx_watchdog_timer_fn+0x10/0x10
? __hrtimer_run_queues+0x300/0x6d0
? sched_clock_cpu+0x69/0x4e0
? __pfx___hrtimer_run_queues+0x10/0x10
? srso_return_thunk+0x5/0x5f
? ktime_get_update_offsets_now+0x7f/0x2a0
? srso_return_thunk+0x5/0x5f
? srso_return_thunk+0x5/0x5f
? hrtimer_interrupt+0x2ca/0x760
? __sysvec_apic_timer_interrupt+0x8c/0x2b0
? sysvec_apic_timer_interrupt+0x6a/0x90
</IRQ>
<TASK>
? asm_sysvec_apic_timer_interrupt+0x16/0x20
? smp_call_function_many_cond+0x1d8/0xbb0
? __pfx_do_kernel_range_flush+0x10/0x10
on_each_cpu_cond_mask+0x20/0x40
flush_tlb_kernel_range+0x19b/0x250
? srso_return_thunk+0x5/0x5f
? kasan_release_vmalloc+0xa7/0xc0
purge_vmap_node+0x357/0x820
? __pfx_purge_vmap_node+0x10/0x10
__purge_vmap_area_lazy+0x5b8/0xa10
drain_vmap_area_work+0x21/0x30
process_one_work+0x661/0x10b0
worker_thread+0x844/0x10e0
? srso_return_thunk+0x5/0x5f
? __kthread_parkme+0x82/0x140
? __pfx_worker_thread+0x10/0x10
kthread+0x2a5/0x370
? __pfx_kthread+0x10/0x10
ret_from_fork+0x30/0x70
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
Debugging Analysis:
1. The following ftrace log shows that the lockup CPU spends too much
time iterating vmap_nodes and flushing TLB when purging vm_area
structures. (Some info is trimmed).
kworker: funcgraph_entry: | drain_vmap_area_work() {
kworker: funcgraph_entry: | mutex_lock() {
kworker: funcgraph_entry: 1.092 us | __cond_resched();
kworker: funcgraph_exit: 3.306 us | }
... ...
kworker: funcgraph_entry: | flush_tlb_kernel_range() {
... ...
kworker: funcgraph_exit: # 7533.649 us | }
... ...
kworker: funcgraph_entry: 2.344 us | mutex_unlock();
kworker: funcgraph_exit: $ 23871554 us | }
The drain_vmap_area_work() spends over 23 seconds.
There are 2805 flush_tlb_kernel_range() calls in the ftrace log.
* One is called in __purge_vmap_area_lazy().
* Others are called by purge_vmap_node->kasan_release_vmalloc.
purge_vmap_node() iteratively releases kasan vmalloc
allocations and flushes TLB for each vmap_area.
- [Rough calculation] Each flush_tlb_kernel_range() runs
about 7.5ms.
-- 2804 * 7.5ms = 21.03 seconds.
-- That's why a soft lock is triggered.
2. Extending the soft lockup time can work around the issue (For example,
# echo 60 > /proc/sys/kernel/watchdog_thresh). This confirms the
above-mentioned speculation: drain_vmap_area_work() spends too much
time.
If we combine all TLB flush operations of the KASAN shadow virtual
address into one operation in the call path
'purge_vmap_node()->kasan_release_vmalloc()', the running time of
drain_vmap_area_work() can be saved greatly. The idea is from the
flush_tlb_kernel_range() call in __purge_vmap_area_lazy(). And, the
soft lockup won't be triggered.
Here is the test result based on 6.10:
[6.10 wo/ the patch]
1. ftrace latency profiling (record a trace if the latency > 20s).
echo 20000000 > /sys/kernel/debug/tracing/tracing_thresh
echo drain_vmap_area_work > /sys/kernel/debug/tracing/set_graph_function
echo function_graph > /sys/kernel/debug/tracing/current_tracer
echo 1 > /sys/kernel/debug/tracing/tracing_on
2. Run `make -j $(nproc)` to compile the kernel source
3. Once the soft lockup is reproduced, check the ftrace log:
cat /sys/kernel/debug/tracing/trace
# tracer: function_graph
#
# CPU DURATION FUNCTION CALLS
# | | | | | | |
76) $ 50412985 us | } /* __purge_vmap_area_lazy */
76) $ 50412997 us | } /* drain_vmap_area_work */
76) $ 29165911 us | } /* __purge_vmap_area_lazy */
76) $ 29165926 us | } /* drain_vmap_area_work */
91) $ 53629423 us | } /* __purge_vmap_area_lazy */
91) $ 53629434 us | } /* drain_vmap_area_work */
91) $ 28121014 us | } /* __purge_vmap_area_lazy */
91) $ 28121026 us | } /* drain_vmap_area_work */
[6.10 w/ the patch]
1. Repeat step 1-2 in "[6.10 wo/ the patch]"
2. The soft lockup is not triggered and ftrace log is empty.
cat /sys/kernel/debug/tracing/trace
# tracer: function_graph
#
# CPU DURATION FUNCTION CALLS
# | | | | | | |
3. Setting 'tracing_thresh' to 10/5 seconds does not get any ftrace
log.
4. Setting 'tracing_thresh' to 1 second gets ftrace log.
cat /sys/kernel/debug/tracing/trace
# tracer: function_graph
#
# CPU DURATION FUNCTION CALLS
# | | | | | | |
23) $ 1074942 us | } /* __purge_vmap_area_lazy */
23) $ 1074950 us | } /* drain_vmap_area_work */
The worst execution time of drain_vmap_area_work() is about 1 second.
Link: https://lore.kernel.org/lkml/ZqFlawuVnOMY2k3E@pc638.lan/
Link: https://lkml.kernel.org/r/20240726165246.31326-1-ahuang12@lenovo.com
Fixes: 282631cb2447 ("mm: vmalloc: remove global purge_vmap_area_root rb-tree")
Signed-off-by: Adrian Huang <ahuang12@lenovo.com>
Co-developed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Tested-by: Jiwei Sun <sunjw10@lenovo.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"Along with the usual shower of singleton patches, notable patch series
in this pull request are:
- "Align kvrealloc() with krealloc()" from Danilo Krummrich. Adds
consistency to the APIs and behaviour of these two core allocation
functions. This also simplifies/enables Rustification.
- "Some cleanups for shmem" from Baolin Wang. No functional changes -
mode code reuse, better function naming, logic simplifications.
- "mm: some small page fault cleanups" from Josef Bacik. No
functional changes - code cleanups only.
- "Various memory tiering fixes" from Zi Yan. A small fix and a
little cleanup.
- "mm/swap: remove boilerplate" from Yu Zhao. Code cleanups and
simplifications and .text shrinkage.
- "Kernel stack usage histogram" from Pasha Tatashin and Shakeel
Butt. This is a feature, it adds new feilds to /proc/vmstat such as
$ grep kstack /proc/vmstat
kstack_1k 3
kstack_2k 188
kstack_4k 11391
kstack_8k 243
kstack_16k 0
which tells us that 11391 processes used 4k of stack while none at
all used 16k. Useful for some system tuning things, but
partivularly useful for "the dynamic kernel stack project".
- "kmemleak: support for percpu memory leak detect" from Pavel
Tikhomirov. Teaches kmemleak to detect leaksage of percpu memory.
- "mm: memcg: page counters optimizations" from Roman Gushchin. "3
independent small optimizations of page counters".
- "mm: split PTE/PMD PT table Kconfig cleanups+clarifications" from
David Hildenbrand. Improves PTE/PMD splitlock detection, makes
powerpc/8xx work correctly by design rather than by accident.
- "mm: remove arch_make_page_accessible()" from David Hildenbrand.
Some folio conversions which make arch_make_page_accessible()
unneeded.
- "mm, memcg: cg2 memory{.swap,}.peak write handlers" fro David
Finkel. Cleans up and fixes our handling of the resetting of the
cgroup/process peak-memory-use detector.
- "Make core VMA operations internal and testable" from Lorenzo
Stoakes. Rationalizaion and encapsulation of the VMA manipulation
APIs. With a view to better enable testing of the VMA functions,
even from a userspace-only harness.
- "mm: zswap: fixes for global shrinker" from Takero Funaki. Fix
issues in the zswap global shrinker, resulting in improved
performance.
- "mm: print the promo watermark in zoneinfo" from Kaiyang Zhao. Fill
in some missing info in /proc/zoneinfo.
- "mm: replace follow_page() by folio_walk" from David Hildenbrand.
Code cleanups and rationalizations (conversion to folio_walk())
resulting in the removal of follow_page().
- "improving dynamic zswap shrinker protection scheme" from Nhat
Pham. Some tuning to improve zswap's dynamic shrinker. Significant
reductions in swapin and improvements in performance are shown.
- "mm: Fix several issues with unaccepted memory" from Kirill
Shutemov. Improvements to the new unaccepted memory feature,
- "mm/mprotect: Fix dax puds" from Peter Xu. Implements mprotect on
DAX PUDs. This was missing, although nobody seems to have notied
yet.
- "Introduce a store type enum for the Maple tree" from Sidhartha
Kumar. Cleanups and modest performance improvements for the maple
tree library code.
- "memcg: further decouple v1 code from v2" from Shakeel Butt. Move
more cgroup v1 remnants away from the v2 memcg code.
- "memcg: initiate deprecation of v1 features" from Shakeel Butt.
Adds various warnings telling users that memcg v1 features are
deprecated.
- "mm: swap: mTHP swap allocator base on swap cluster order" from
Chris Li. Greatly improves the success rate of the mTHP swap
allocation.
- "mm: introduce numa_memblks" from Mike Rapoport. Moves various
disparate per-arch implementations of numa_memblk code into generic
code.
- "mm: batch free swaps for zap_pte_range()" from Barry Song. Greatly
improves the performance of munmap() of swap-filled ptes.
- "support large folio swap-out and swap-in for shmem" from Baolin
Wang. With this series we no longer split shmem large folios into
simgle-page folios when swapping out shmem.
- "mm/hugetlb: alloc/free gigantic folios" from Yu Zhao. Nice
performance improvements and code reductions for gigantic folios.
- "support shmem mTHP collapse" from Baolin Wang. Adds support for
khugepaged's collapsing of shmem mTHP folios.
- "mm: Optimize mseal checks" from Pedro Falcato. Fixes an mprotect()
performance regression due to the addition of mseal().
- "Increase the number of bits available in page_type" from Matthew
Wilcox. Increases the number of bits available in page_type!
- "Simplify the page flags a little" from Matthew Wilcox. Many legacy
page flags are now folio flags, so the page-based flags and their
accessors/mutators can be removed.
- "mm: store zero pages to be swapped out in a bitmap" from Usama
Arif. An optimization which permits us to avoid writing/reading
zero-filled zswap pages to backing store.
- "Avoid MAP_FIXED gap exposure" from Liam Howlett. Fixes a race
window which occurs when a MAP_FIXED operqtion is occurring during
an unrelated vma tree walk.
- "mm: remove vma_merge()" from Lorenzo Stoakes. Major rotorooting of
the vma_merge() functionality, making ot cleaner, more testable and
better tested.
- "misc fixups for DAMON {self,kunit} tests" from SeongJae Park.
Minor fixups of DAMON selftests and kunit tests.
- "mm: memory_hotplug: improve do_migrate_range()" from Kefeng Wang.
Code cleanups and folio conversions.
- "Shmem mTHP controls and stats improvements" from Ryan Roberts.
Cleanups for shmem controls and stats.
- "mm: count the number of anonymous THPs per size" from Barry Song.
Expose additional anon THP stats to userspace for improved tuning.
- "mm: finish isolate/putback_lru_page()" from Kefeng Wang: more
folio conversions and removal of now-unused page-based APIs.
- "replace per-quota region priorities histogram buffer with
per-context one" from SeongJae Park. DAMON histogram
rationalization.
- "Docs/damon: update GitHub repo URLs and maintainer-profile" from
SeongJae Park. DAMON documentation updates.
- "mm/vdpa: correct misuse of non-direct-reclaim __GFP_NOFAIL and
improve related doc and warn" from Jason Wang: fixes usage of page
allocator __GFP_NOFAIL and GFP_ATOMIC flags.
- "mm: split underused THPs" from Yu Zhao. Improve THP=always policy.
This was overprovisioning THPs in sparsely accessed memory areas.
- "zram: introduce custom comp backends API" frm Sergey Senozhatsky.
Add support for zram run-time compression algorithm tuning.
- "mm: Care about shadow stack guard gap when getting an unmapped
area" from Mark Brown. Fix up the various arch_get_unmapped_area()
implementations to better respect guard areas.
- "Improve mem_cgroup_iter()" from Kinsey Ho. Improve the reliability
of mem_cgroup_iter() and various code cleanups.
- "mm: Support huge pfnmaps" from Peter Xu. Extends the usage of huge
pfnmap support.
- "resource: Fix region_intersects() vs add_memory_driver_managed()"
from Huang Ying. Fix a bug in region_intersects() for systems with
CXL memory.
- "mm: hwpoison: two more poison recovery" from Kefeng Wang. Teaches
a couple more code paths to correctly recover from the encountering
of poisoned memry.
- "mm: enable large folios swap-in support" from Barry Song. Support
the swapin of mTHP memory into appropriately-sized folios, rather
than into single-page folios"
* tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (416 commits)
zram: free secondary algorithms names
uprobes: turn xol_area->pages[2] into xol_area->page
uprobes: introduce the global struct vm_special_mapping xol_mapping
Revert "uprobes: use vm_special_mapping close() functionality"
mm: support large folios swap-in for sync io devices
mm: add nr argument in mem_cgroup_swapin_uncharge_swap() helper to support large folios
mm: fix swap_read_folio_zeromap() for large folios with partial zeromap
mm/debug_vm_pgtable: Use pxdp_get() for accessing page table entries
set_memory: add __must_check to generic stubs
mm/vma: return the exact errno in vms_gather_munmap_vmas()
memcg: cleanup with !CONFIG_MEMCG_V1
mm/show_mem.c: report alloc tags in human readable units
mm: support poison recovery from copy_present_page()
mm: support poison recovery from do_cow_fault()
resource, kunit: add test case for region_intersects()
resource: make alloc_free_mem_region() works for iomem_resource
mm: z3fold: deprecate CONFIG_Z3FOLD
vfio/pci: implement huge_fault support
mm/arm64: support large pfn mappings
mm/x86: support large pfn mappings
...
|
|
In many places, in the comments, we use both "higher-order" and
"high-order" to describe the non 0-order pages. That is confusing,
because a "higher-order" statement does not reflect what it is compared
with.
Link: https://lkml.kernel.org/r/20240906095049.3486-1-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Suggested-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Use helper function va_size() to improve code readability. No functional
modification involved.
Link: https://lkml.kernel.org/r/20240906102539.3537207-1-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
list_head can be initialized automatically with LIST_HEAD() instead of
calling INIT_LIST_HEAD(). Here we can simplify the code.
Link: https://lkml.kernel.org/r/20240828041216.1222582-1-lihongbo22@huawei.com
Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The aim is to simplify and making the vm_area_alloc_pages()
function less confusing as it became more clogged nowadays:
- eliminate a "bulk_gfp" variable and do not overwrite a gfp
flag for bulk allocator;
- drop __GFP_NOFAIL flag for high-order-page requests on upper
layer. It becomes less spread between levels when it comes to
__GFP_NOFAIL allocations;
- add a comment about a fallback path if high-order attempt is
unsuccessful because for such cases __GFP_NOFAIL is dropped;
- fix a typo in a commit message.
Link: https://lkml.kernel.org/r/20240827190916.34242-1-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
In commit 21e516b913c1 ("mm: vmalloc: dump page owner info if page is
already mapped"), a BUG_ON macro was changed into an if statement, where
the compiler optimization hint introduced in the BUG_ON macro was removed
along with this change. This patch adds back the hint.
Link: https://lkml.kernel.org/r/20240814-fix_vmap_unlikely-v1-1-cd7954775f12@gmail.com
Fixes: 21e516b913c1 ("mm: vmalloc: dump page owner info if page is already mapped")
Signed-off-by: Miao Wang <shankerwangmiao@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Hariom Panthi <hariom1.p@samsung.com>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Patch series "Align kvrealloc() with krealloc()", v2.
Besides the obvious (and desired) difference between krealloc() and
kvrealloc(), there is some inconsistency in their function signatures and
behavior:
- krealloc() frees the memory when the requested size is zero, whereas
kvrealloc() simply returns a pointer to the existing allocation.
- krealloc() behaves like kmalloc() if a NULL pointer is passed, whereas
kvrealloc() does not accept a NULL pointer at all and, if passed, would fault
instead.
- krealloc() is self-contained, whereas kvrealloc() relies on the caller to
provide the size of the previous allocation.
Inconsistent behavior throughout allocation APIs is error prone, hence
make kvrealloc() behave like krealloc(), which seems superior in all
mentioned aspects.
In order to be able to get rid of kvrealloc()'s oldsize parameter,
introduce vrealloc() and make use of it in kvrealloc().
Making use of vrealloc() in kvrealloc() also provides oppertunities to
grow (and shrink) allocations more efficiently. For instance, vrealloc()
can be optimized to allocate and map additional pages to grow the
allocation or unmap and free unused pages to shrink the allocation.
Besides the above, those functions are required by Rust's allocator abstractons
[1] (rework based on this series in [2]). With `Vec` or `KVec` respectively,
potentially growing (and shrinking) data structures are rather common.
[1] https://lore.kernel.org/lkml/20240704170738.3621-1-dakr@redhat.com/
[2] https://git.kernel.org/pub/scm/linux/kernel/git/dakr/linux.git/log/?h=rust/mm
This patch (of 2):
Implement vrealloc() analogous to krealloc().
Currently, krealloc() requires the caller to pass the size of the previous
memory allocation, which, instead, should be self-contained.
We attempt to fix this in a subsequent patch which, in order to do so,
requires vrealloc().
Besides that, we need realloc() functions for kernel allocators in Rust
too. With `Vec` or `KVec` respectively, potentially growing (and
shrinking) data structures are rather common.
[dakr@kernel.org: fix missing nommu implementation]
Link: https://lkml.kernel.org/r/20240725141227.13954-1-dakr@kernel.org
[dakr@kernel.org: document concurrency restrictions]
Link: https://lkml.kernel.org/r/20240725125442.4957-1-dakr@kernel.org
[dakr@kernel.org: consider spare memory for __GFP_ZERO]
Link: https://lkml.kernel.org/r/20240730185049.6244-3-dakr@kernel.org
[dakr@kernel.org: properly document __GFP_ZERO behavior]
Link: https://lkml.kernel.org/r/20240730185049.6244-4-dakr@kernel.org
Link: https://lkml.kernel.org/r/20240722163111.4766-1-dakr@kernel.org
Link: https://lkml.kernel.org/r/20240722163111.4766-2-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Chandan Babu R <chandan.babu@oracle.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Uladzislau Rezki <urezki@gmail.com>
Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
When running the vmalloc stress on a 448-core system, observe the average
latency of purge_vmap_node() is about 2 seconds by using the eBPF/bcc
'funclatency.py' tool [1].
# /your-git-repo/bcc/tools/funclatency.py -u purge_vmap_node & pid1=$! && sleep 8 && modprobe test_vmalloc nr_threads=$(nproc) run_test_mask=0x7; kill -SIGINT $pid1
usecs : count distribution
0 -> 1 : 0 | |
2 -> 3 : 29 | |
4 -> 7 : 19 | |
8 -> 15 : 56 | |
16 -> 31 : 483 |**** |
32 -> 63 : 1548 |************ |
64 -> 127 : 2634 |********************* |
128 -> 255 : 2535 |********************* |
256 -> 511 : 1776 |************** |
512 -> 1023 : 1015 |******** |
1024 -> 2047 : 573 |**** |
2048 -> 4095 : 488 |**** |
4096 -> 8191 : 1091 |********* |
8192 -> 16383 : 3078 |************************* |
16384 -> 32767 : 4821 |****************************************|
32768 -> 65535 : 3318 |*************************** |
65536 -> 131071 : 1718 |************** |
131072 -> 262143 : 2220 |****************** |
262144 -> 524287 : 1147 |********* |
524288 -> 1048575 : 1179 |********* |
1048576 -> 2097151 : 822 |****** |
2097152 -> 4194303 : 906 |******* |
4194304 -> 8388607 : 2148 |***************** |
8388608 -> 16777215 : 4497 |************************************* |
16777216 -> 33554431 : 289 |** |
avg = 2041714 usecs, total: 78381401772 usecs, count: 38390
The worst case is over 16-33 seconds, so soft lockup is triggered [2].
[Root Cause]
1) Each purge_list has the long list. The following shows the number of
vmap_area is purged.
crash> p vmap_nodes
vmap_nodes = $27 = (struct vmap_node *) 0xff2de5a900100000
crash> vmap_node 0xff2de5a900100000 128 | grep nr_purged
nr_purged = 663070
...
nr_purged = 821670
nr_purged = 692214
nr_purged = 726808
...
2) atomic_long_sub() employs the 'lock' prefix to ensure the atomic
operation when purging each vmap_area. However, the iteration is over
600000 vmap_area (See 'nr_purged' above).
Here is objdump output:
$ objdump -D vmlinux
ffffffff813e8c80 <purge_vmap_node>:
...
ffffffff813e8d70: f0 48 29 2d 68 0c bb lock sub %rbp,0x2bb0c68(%rip)
...
Quote from "Instruction tables" pdf file [3]:
Instructions with a LOCK prefix have a long latency that depends on
cache organization and possibly RAM speed. If there are multiple
processors or cores or direct memory access (DMA) devices, then all
locked instructions will lock a cache line for exclusive access,
which may involve RAM access. A LOCK prefix typically costs more
than a hundred clock cycles, even on single-processor systems.
That's why the latency of purge_vmap_node() dramatically increases
on a many-core system: One core is busy on purging each vmap_area of
the *long* purge_list and executing atomic_long_sub() for each
vmap_area, while other cores free vmalloc allocations and execute
atomic_long_add_return() in free_vmap_area_noflush().
[Solution]
Employ a local variable to record the total purged pages, and execute
atomic_long_sub() after the traversal of the purge_list is done. The
experiment result shows the latency improvement is 99%.
[Experiment Result]
1) System Configuration: Three servers (with HT-enabled) are tested.
* 72-core server: 3rd Gen Intel Xeon Scalable Processor*1
* 192-core server: 5th Gen Intel Xeon Scalable Processor*2
* 448-core server: AMD Zen 4 Processor*2
2) Kernel Config
* CONFIG_KASAN is disabled
3) The data in column "w/o patch" and "w/ patch"
* Unit: micro seconds (us)
* Each data is the average of 3-time measurements
System w/o patch (us) w/ patch (us) Improvement (%)
--------------- -------------- ------------- -------------
72-core server 2194 14 99.36%
192-core server 143799 1139 99.21%
448-core server 1992122 6883 99.65%
[1] https://github.com/iovisor/bcc/blob/master/tools/funclatency.py
[2] https://gist.github.com/AdrianHuang/37c15f67b45407b83c2d32f918656c12
[3] https://www.agner.org/optimize/instruction_tables.pdf
Link: https://lkml.kernel.org/r/20240829130633.2184-1-ahuang12@lenovo.com
Signed-off-by: Adrian Huang <ahuang12@lenovo.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Commit 8c61291fd850 ("mm: fix incorrect vbq reference in
purge_fragmented_block") extended the 'vmap_block' structure to contain a
'cpu' field which is set at allocation time to the id of the initialising
CPU.
When a new 'vmap_block' is being instantiated by new_vmap_block(), the
partially initialised structure is added to the local 'vmap_block_queue'
xarray before the 'cpu' field has been initialised. If another CPU is
concurrently walking the xarray (e.g. via vm_unmap_aliases()), then it
may perform an out-of-bounds access to the remote queue thanks to an
uninitialised index.
This has been observed as UBSAN errors in Android:
| Internal error: UBSAN: array index out of bounds: 00000000f2005512 [#1] PREEMPT SMP
|
| Call trace:
| purge_fragmented_block+0x204/0x21c
| _vm_unmap_aliases+0x170/0x378
| vm_unmap_aliases+0x1c/0x28
| change_memory_common+0x1dc/0x26c
| set_memory_ro+0x18/0x24
| module_enable_ro+0x98/0x238
| do_init_module+0x1b0/0x310
Move the initialisation of 'vb->cpu' in new_vmap_block() ahead of the
addition to the xarray.
Link: https://lkml.kernel.org/r/20240812171606.17486-1-will@kernel.org
Fixes: 8c61291fd850 ("mm: fix incorrect vbq reference in purge_fragmented_block")
Signed-off-by: Will Deacon <will@kernel.org>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Cc: Hailong.Liu <hailong.liu@oppo.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
fallback to order 0
The __vmap_pages_range_noflush() assumes its argument pages** contains
pages with the same page shift. However, since commit e9c3cda4d86e ("mm,
vmalloc: fix high order __GFP_NOFAIL allocations"), if gfp_flags includes
__GFP_NOFAIL with high order in vm_area_alloc_pages() and page allocation
failed for high order, the pages** may contain two different page shifts
(high order and order-0). This could lead __vmap_pages_range_noflush() to
perform incorrect mappings, potentially resulting in memory corruption.
Users might encounter this as follows (vmap_allow_huge = true, 2M is for
PMD_SIZE):
kvmalloc(2M, __GFP_NOFAIL|GFP_X)
__vmalloc_node_range_noprof(vm_flags=VM_ALLOW_HUGE_VMAP)
vm_area_alloc_pages(order=9) ---> order-9 allocation failed and fallback to order-0
vmap_pages_range()
vmap_pages_range_noflush()
__vmap_pages_range_noflush(page_shift = 21) ----> wrong mapping happens
We can remove the fallback code because if a high-order allocation fails,
__vmalloc_node_range_noprof() will retry with order-0. Therefore, it is
unnecessary to fallback to order-0 here. Therefore, fix this by removing
the fallback code.
Link: https://lkml.kernel.org/r/20240808122019.3361-1-hailong.liu@oppo.com
Fixes: e9c3cda4d86e ("mm, vmalloc: fix high order __GFP_NOFAIL allocations")
Signed-off-by: Hailong Liu <hailong.liu@oppo.com>
Reported-by: Tangquan Zheng <zhengtangquan@oppo.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Acked-by: Barry Song <baohua@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
crashes from deferred split racing folio migration", needed by "mm:
migrate: split folio_migrate_mapping()".
|
|
The problem is that there are systems where cpu_possible_mask has gaps
between set CPUs, for example SPARC. In this scenario addr_to_vb_xa()
hash function can return an index which accesses to not-possible and not
setup CPU area using per_cpu() macro. This results in an oops on SPARC.
A per-cpu vmap_block_queue is also used as hash table, incorrectly
assuming the cpu_possible_mask has no gaps. Fix it by adjusting an index
to a next possible CPU.
Link: https://lkml.kernel.org/r/20240626140330.89836-1-urezki@gmail.com
Fixes: 062eacf57ad9 ("mm: vmalloc: remove a global vmap_blocks xarray")
Reported-by: Nick Bowler <nbowler@draconx.ca>
Closes: https://lore.kernel.org/linux-kernel/ZntjIE6msJbF8zTa@MiWiFi-R3L-srv/T/
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Hailong.Liu <hailong.liu@oppo.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
'vmap allocation for size %lu failed: use vmalloc=<size> to increase size'
The above warning is seen in the kernel functionality for allocation of
the restricted virtual memory range till exhaustion.
This message is misleading because 'vmalloc=' is supported on arm32, x86
platforms and is not a valid kernel parameter on a number of other
platforms (in particular its not supported on arm64, alpha, loongarch,
arc, csky, hexagon, microblaze, mips, nios2, openrisc, parisc, m64k,
powerpc, riscv, sh, um, xtensa, s390, sparc). With the update, the output
gets modified to include the function parameters along with the start and
end of the virtual memory range allowed.
The warning message after fix on kernel version 6.10.0-rc1+:
vmalloc_node_range for size 33619968 failed: Address range restricted between 0xffff800082640000 - 0xffff800084650000
Backtrace with the misleading error message:
vmap allocation for size 33619968 failed: use vmalloc=<size> to increase size
insmod: vmalloc error: size 33554432, vm_struct allocation failed, mode:0xcc0(GFP_KERNEL), nodemask=(null),cpuset=/,mems_allowed=0
CPU: 46 PID: 1977 Comm: insmod Tainted: G E 6.10.0-rc1+ #79
Hardware name: INGRASYS Yushan Server iSystem TEMP-S000141176+10/Yushan Motherboard, BIOS 2.10.20230517 (SCP: xxx) yyyy/mm/dd
Call trace:
dump_backtrace+0xa0/0x128
show_stack+0x20/0x38
dump_stack_lvl+0x78/0x90
dump_stack+0x18/0x28
warn_alloc+0x12c/0x1b8
__vmalloc_node_range_noprof+0x28c/0x7e0
custom_init+0xb4/0xfff8 [test_driver]
do_one_initcall+0x60/0x290
do_init_module+0x68/0x250
load_module+0x236c/0x2428
init_module_from_file+0x8c/0xd8
__arm64_sys_finit_module+0x1b4/0x388
invoke_syscall+0x78/0x108
el0_svc_common.constprop.0+0x48/0xf0
do_el0_svc+0x24/0x38
el0_svc+0x3c/0x130
el0t_64_sync_handler+0x100/0x130
el0t_64_sync+0x190/0x198
[Shubhang@os.amperecomputing.com: v5]
Link: https://lkml.kernel.org/r/CH2PR01MB5894B0182EA0B28DF2EFB916F5C72@CH2PR01MB5894.prod.exchangelabs.com
Link: https://lkml.kernel.org/r/MN2PR01MB59025CC02D1D29516527A693F5C62@MN2PR01MB5902.prod.exchangelabs.com
Signed-off-by: Shubhang Kaushik <shubhang@os.amperecomputing.com>
Reviewed-by: Christoph Lameter (Ampere) <cl@linux.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Xiongwei Song <xiongwei.song@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Use __this_cpu_try_cmpxchg() instead of __this_cpu_cmpxchg (*ptr, old,
new) == old in preload_this_cpu_lock(). x86 CMPXCHG instruction returns
success in ZF flag, so this change saves a compare after cmpxchg.
The generated code improves from:
4bb6: 48 85 f6 test %rsi,%rsi
4bb9: 0f 84 10 fa ff ff je 45cf <...>
4bbf: 4c 89 e8 mov %r13,%rax
4bc2: 65 48 0f b1 35 00 00 cmpxchg %rsi,%gs:0x0(%rip)
4bc9: 00 00
4bcb: 48 85 c0 test %rax,%rax
4bce: 0f 84 fb f9 ff ff je 45cf <...>
to:
4bb6: 48 85 f6 test %rsi,%rsi
4bb9: 0f 84 10 fa ff ff je 45cf <...>
4bbf: 4c 89 e8 mov %r13,%rax
4bc2: 65 48 0f b1 35 00 00 cmpxchg %rsi,%gs:0x0(%rip)
4bc9: 00 00
4bcb: 0f 84 fe f9 ff ff je 45cf <...>
No functional change intended.
Link: https://lkml.kernel.org/r/20240528144345.5980-2-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
xa_for_each() in _vm_unmap_aliases() loops through all vbs. However,
since commit 062eacf57ad9 ("mm: vmalloc: remove a global vmap_blocks
xarray") the vb from xarray may not be on the corresponding CPU
vmap_block_queue. Consequently, purge_fragmented_block() might use the
wrong vbq->lock to protect the free list, leading to vbq->free breakage.
Incorrect lock protection can exhaust all vmalloc space as follows:
CPU0 CPU1
+--------------------------------------------+
| +--------------------+ +-----+ |
+--> | |---->| |------+
| CPU1:vbq free_list | | vb1 |
+--- | |<----| |<-----+
| +--------------------+ +-----+ |
+--------------------------------------------+
_vm_unmap_aliases() vb_alloc()
new_vmap_block()
xa_for_each(&vbq->vmap_blocks, idx, vb)
--> vb in CPU1:vbq->freelist
purge_fragmented_block(vb)
spin_lock(&vbq->lock) spin_lock(&vbq->lock)
--> use CPU0:vbq->lock --> use CPU1:vbq->lock
list_del_rcu(&vb->free_list) list_add_tail_rcu(&vb->free_list, &vbq->free)
__list_del(vb->prev, vb->next)
next->prev = prev
+--------------------+
| |
| CPU1:vbq free_list |
+---| |<--+
| +--------------------+ |
+----------------------------+
__list_add(new, head->prev, head)
+--------------------------------------------+
| +--------------------+ +-----+ |
+--> | |---->| |------+
| CPU1:vbq free_list | | vb2 |
+--- | |<----| |<-----+
| +--------------------+ +-----+ |
+--------------------------------------------+
prev->next = next
+--------------------------------------------+
|----------------------------+ |
| +--------------------+ | +-----+ |
+--> | |--+ | |------+
| CPU1:vbq free_list | | vb2 |
+--- | |<----| |<-----+
| +--------------------+ +-----+ |
+--------------------------------------------+
Here’s a list breakdown. All vbs, which were to be added to
‘prev’, cannot be used by list_for_each_entry_rcu(vb, &vbq->free,
free_list) in vb_alloc(). Thus, vmalloc space is exhausted.
This issue affects both erofs and f2fs, the stacktrace is as follows:
erofs:
[<ffffffd4ffb93ad4>] __switch_to+0x174
[<ffffffd4ffb942f0>] __schedule+0x624
[<ffffffd4ffb946f4>] schedule+0x7c
[<ffffffd4ffb947cc>] schedule_preempt_disabled+0x24
[<ffffffd4ffb962ec>] __mutex_lock+0x374
[<ffffffd4ffb95998>] __mutex_lock_slowpath+0x14
[<ffffffd4ffb95954>] mutex_lock+0x24
[<ffffffd4fef2900c>] reclaim_and_purge_vmap_areas+0x44
[<ffffffd4fef25908>] alloc_vmap_area+0x2e0
[<ffffffd4fef24ea0>] vm_map_ram+0x1b0
[<ffffffd4ff1b46f4>] z_erofs_lz4_decompress+0x278
[<ffffffd4ff1b8ac4>] z_erofs_decompress_queue+0x650
[<ffffffd4ff1b8328>] z_erofs_runqueue+0x7f4
[<ffffffd4ff1b66a8>] z_erofs_read_folio+0x104
[<ffffffd4feeb6fec>] filemap_read_folio+0x6c
[<ffffffd4feeb68c4>] filemap_fault+0x300
[<ffffffd4fef0ecac>] __do_fault+0xc8
[<ffffffd4fef0c908>] handle_mm_fault+0xb38
[<ffffffd4ffb9f008>] do_page_fault+0x288
[<ffffffd4ffb9ed64>] do_translation_fault[jt]+0x40
[<ffffffd4fec39c78>] do_mem_abort+0x58
[<ffffffd4ffb8c3e4>] el0_ia+0x70
[<ffffffd4ffb8c260>] el0t_64_sync_handler[jt]+0xb0
[<ffffffd4fec11588>] ret_to_user[jt]+0x0
f2fs:
[<ffffffd4ffb93ad4>] __switch_to+0x174
[<ffffffd4ffb942f0>] __schedule+0x624
[<ffffffd4ffb946f4>] schedule+0x7c
[<ffffffd4ffb947cc>] schedule_preempt_disabled+0x24
[<ffffffd4ffb962ec>] __mutex_lock+0x374
[<ffffffd4ffb95998>] __mutex_lock_slowpath+0x14
[<ffffffd4ffb95954>] mutex_lock+0x24
[<ffffffd4fef2900c>] reclaim_and_purge_vmap_areas+0x44
[<ffffffd4fef25908>] alloc_vmap_area+0x2e0
[<ffffffd4fef24ea0>] vm_map_ram+0x1b0
[<ffffffd4ff1a3b60>] f2fs_prepare_decomp_mem+0x144
[<ffffffd4ff1a6c24>] f2fs_alloc_dic+0x264
[<ffffffd4ff175468>] f2fs_read_multi_pages+0x428
[<ffffffd4ff17b46c>] f2fs_mpage_readpages+0x314
[<ffffffd4ff1785c4>] f2fs_readahead+0x50
[<ffffffd4feec3384>] read_pages+0x80
[<ffffffd4feec32c0>] page_cache_ra_unbounded+0x1a0
[<ffffffd4feec39e8>] page_cache_ra_order+0x274
[<ffffffd4feeb6cec>] do_sync_mmap_readahead+0x11c
[<ffffffd4feeb6764>] filemap_fault+0x1a0
[<ffffffd4ff1423bc>] f2fs_filemap_fault+0x28
[<ffffffd4fef0ecac>] __do_fault+0xc8
[<ffffffd4fef0c908>] handle_mm_fault+0xb38
[<ffffffd4ffb9f008>] do_page_fault+0x288
[<ffffffd4ffb9ed64>] do_translation_fault[jt]+0x40
[<ffffffd4fec39c78>] do_mem_abort+0x58
[<ffffffd4ffb8c3e4>] el0_ia+0x70
[<ffffffd4ffb8c260>] el0t_64_sync_handler[jt]+0xb0
[<ffffffd4fec11588>] ret_to_user[jt]+0x0
To fix this, introducee cpu within vmap_block to record which this vb
belongs to.
Link: https://lkml.kernel.org/r/20240614021352.1822225-1-zhaoyang.huang@unisoc.com
Link: https://lkml.kernel.org/r/20240607023116.1720640-1-zhaoyang.huang@unisoc.com
Fixes: fc1e0d980037 ("mm/vmalloc: prevent stale TLBs in fully utilized blocks")
Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Suggested-by: Hailong.Liu <hailong.liu@oppo.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
After commit 2c9e5d4a0082 ("bpf: remove CONFIG_BPF_JIT dependency on
CONFIG_MODULES of") CONFIG_BPF_JIT does not depend on CONFIG_MODULES any
more and bpf jit also uses the [MODULES_VADDR, MODULES_END] memory region.
But is_vmalloc_or_module_addr() still checks CONFIG_MODULES, which then
returns false for a bpf jit memory region when CONFIG_MODULES is not
defined. It leads to the following kernel BUG:
[ 1.567023] ------------[ cut here ]------------
[ 1.567883] kernel BUG at mm/vmalloc.c:745!
[ 1.568477] Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
[ 1.569367] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.9.0+ #448
[ 1.570247] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
[ 1.570786] RIP: 0010:vmalloc_to_page+0x48/0x1ec
[ 1.570786] Code: 0f 00 00 e8 eb 1a 05 00 b8 37 00 00 00 48 ba fe ff ff ff ff 1f 00 00 4c 03 25 76 49 c6 02 48 c1 e0 28 48 01 e8 48 39 d0 76 02 <0f> 0b 4c 89 e7 e8 bf 1a 05 00 49 8b 04 24 48 a9 9f ff ff ff 0f 84
[ 1.570786] RSP: 0018:ffff888007787960 EFLAGS: 00010212
[ 1.570786] RAX: 000036ffa0000000 RBX: 0000000000000640 RCX: ffffffff8147e93c
[ 1.570786] RDX: 00001ffffffffffe RSI: dffffc0000000000 RDI: ffffffff840e32c8
[ 1.570786] RBP: ffffffffa0000000 R08: 0000000000000000 R09: 0000000000000000
[ 1.570786] R10: ffff888007787a88 R11: ffffffff8475d8e7 R12: ffffffff83e80ff8
[ 1.570786] R13: 0000000000000640 R14: 0000000000000640 R15: 0000000000000640
[ 1.570786] FS: 0000000000000000(0000) GS:ffff88806cc00000(0000) knlGS:0000000000000000
[ 1.570786] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1.570786] CR2: ffff888006a01000 CR3: 0000000003e80000 CR4: 0000000000350ef0
[ 1.570786] Call Trace:
[ 1.570786] <TASK>
[ 1.570786] ? __die_body+0x1b/0x58
[ 1.570786] ? die+0x31/0x4b
[ 1.570786] ? do_trap+0x9d/0x138
[ 1.570786] ? vmalloc_to_page+0x48/0x1ec
[ 1.570786] ? do_error_trap+0xcd/0x102
[ 1.570786] ? vmalloc_to_page+0x48/0x1ec
[ 1.570786] ? vmalloc_to_page+0x48/0x1ec
[ 1.570786] ? handle_invalid_op+0x2f/0x38
[ 1.570786] ? vmalloc_to_page+0x48/0x1ec
[ 1.570786] ? exc_invalid_op+0x2b/0x41
[ 1.570786] ? asm_exc_invalid_op+0x16/0x20
[ 1.570786] ? vmalloc_to_page+0x26/0x1ec
[ 1.570786] ? vmalloc_to_page+0x48/0x1ec
[ 1.570786] __text_poke+0xb6/0x458
[ 1.570786] ? __pfx_text_poke_memcpy+0x10/0x10
[ 1.570786] ? __pfx___mutex_lock+0x10/0x10
[ 1.570786] ? __pfx___text_poke+0x10/0x10
[ 1.570786] ? __pfx_get_random_u32+0x10/0x10
[ 1.570786] ? srso_return_thunk+0x5/0x5f
[ 1.570786] text_poke_copy_locked+0x70/0x84
[ 1.570786] text_poke_copy+0x32/0x4f
[ 1.570786] bpf_arch_text_copy+0xf/0x27
[ 1.570786] bpf_jit_binary_pack_finalize+0x26/0x5a
[ 1.570786] bpf_int_jit_compile+0x576/0x8ad
[ 1.570786] ? __pfx_bpf_int_jit_compile+0x10/0x10
[ 1.570786] ? srso_return_thunk+0x5/0x5f
[ 1.570786] ? __kmalloc_node_track_caller+0x2b5/0x2e0
[ 1.570786] bpf_prog_select_runtime+0x7c/0x199
[ 1.570786] bpf_prepare_filter+0x1e9/0x25b
[ 1.570786] ? __pfx_bpf_prepare_filter+0x10/0x10
[ 1.570786] ? srso_return_thunk+0x5/0x5f
[ 1.570786] ? _find_next_bit+0x29/0x7e
[ 1.570786] bpf_prog_create+0xb8/0xe0
[ 1.570786] ptp_classifier_init+0x75/0xa1
[ 1.570786] ? __pfx_ptp_classifier_init+0x10/0x10
[ 1.570786] ? srso_return_thunk+0x5/0x5f
[ 1.570786] ? register_pernet_subsys+0x36/0x42
[ 1.570786] ? srso_return_thunk+0x5/0x5f
[ 1.570786] sock_init+0x99/0xa3
[ 1.570786] ? __pfx_sock_init+0x10/0x10
[ 1.570786] do_one_initcall+0x104/0x2c4
[ 1.570786] ? __pfx_do_one_initcall+0x10/0x10
[ 1.570786] ? parameq+0x25/0x2d
[ 1.570786] ? rcu_is_watching+0x1c/0x3c
[ 1.570786] ? trace_kmalloc+0x81/0xb2
[ 1.570786] ? srso_return_thunk+0x5/0x5f
[ 1.570786] ? __kmalloc+0x29c/0x2c7
[ 1.570786] ? srso_return_thunk+0x5/0x5f
[ 1.570786] do_initcalls+0xf9/0x123
[ 1.570786] kernel_init_freeable+0x24f/0x289
[ 1.570786] ? __pfx_kernel_init+0x10/0x10
[ 1.570786] kernel_init+0x19/0x13a
[ 1.570786] ret_from_fork+0x24/0x41
[ 1.570786] ? __pfx_kernel_init+0x10/0x10
[ 1.570786] ret_from_fork_asm+0x1a/0x30
[ 1.570786] </TASK>
[ 1.570819] ---[ end trace 0000000000000000 ]---
[ 1.571463] RIP: 0010:vmalloc_to_page+0x48/0x1ec
[ 1.572111] Code: 0f 00 00 e8 eb 1a 05 00 b8 37 00 00 00 48 ba fe ff ff ff ff 1f 00 00 4c 03 25 76 49 c6 02 48 c1 e0 28 48 01 e8 48 39 d0 76 02 <0f> 0b 4c 89 e7 e8 bf 1a 05 00 49 8b 04 24 48 a9 9f ff ff ff 0f 84
[ 1.574632] RSP: 0018:ffff888007787960 EFLAGS: 00010212
[ 1.575129] RAX: 000036ffa0000000 RBX: 0000000000000640 RCX: ffffffff8147e93c
[ 1.576097] RDX: 00001ffffffffffe RSI: dffffc0000000000 RDI: ffffffff840e32c8
[ 1.577084] RBP: ffffffffa0000000 R08: 0000000000000000 R09: 0000000000000000
[ 1.578077] R10: ffff888007787a88 R11: ffffffff8475d8e7 R12: ffffffff83e80ff8
[ 1.578810] R13: 0000000000000640 R14: 0000000000000640 R15: 0000000000000640
[ 1.579823] FS: 0000000000000000(0000) GS:ffff88806cc00000(0000) knlGS:0000000000000000
[ 1.580992] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1.581869] CR2: ffff888006a01000 CR3: 0000000003e80000 CR4: 0000000000350ef0
[ 1.582800] Kernel panic - not syncing: Fatal exception
[ 1.583765] ---[ end Kernel panic - not syncing: Fatal exception ]---
Fix this by checking CONFIG_EXECMEM instead.
Link: https://lkml.kernel.org/r/20240528160838.102223-1-xiyou.wangcong@gmail.com
Fixes: 2c9e5d4a0082 ("bpf: remove CONFIG_BPF_JIT dependency on CONFIG_MODULES of")
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
commit a421ef303008 ("mm: allow !GFP_KERNEL allocations for kvmalloc")
includes support for __GFP_NOFAIL, but it presents a conflict with commit
dd544141b9eb ("vmalloc: back off when the current task is OOM-killed"). A
possible scenario is as follows:
process-a
__vmalloc_node_range(GFP_KERNEL | __GFP_NOFAIL)
__vmalloc_area_node()
vm_area_alloc_pages()
--> oom-killer send SIGKILL to process-a
if (fatal_signal_pending(current)) break;
--> return NULL;
To fix this, do not check fatal_signal_pending() in vm_area_alloc_pages()
if __GFP_NOFAIL set.
This issue occurred during OPLUS KASAN TEST. Below is part of the log
-> oom-killer sends signal to process
[65731.222840] [ T1308] oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),cpuset=/,mems_allowed=0,global_oom,task_memcg=/apps/uid_10198,task=gs.intelligence,pid=32454,uid=10198
[65731.259685] [T32454] Call trace:
[65731.259698] [T32454] dump_backtrace+0xf4/0x118
[65731.259734] [T32454] show_stack+0x18/0x24
[65731.259756] [T32454] dump_stack_lvl+0x60/0x7c
[65731.259781] [T32454] dump_stack+0x18/0x38
[65731.259800] [T32454] mrdump_common_die+0x250/0x39c [mrdump]
[65731.259936] [T32454] ipanic_die+0x20/0x34 [mrdump]
[65731.260019] [T32454] atomic_notifier_call_chain+0xb4/0xfc
[65731.260047] [T32454] notify_die+0x114/0x198
[65731.260073] [T32454] die+0xf4/0x5b4
[65731.260098] [T32454] die_kernel_fault+0x80/0x98
[65731.260124] [T32454] __do_kernel_fault+0x160/0x2a8
[65731.260146] [T32454] do_bad_area+0x68/0x148
[65731.260174] [T32454] do_mem_abort+0x151c/0x1b34
[65731.260204] [T32454] el1_abort+0x3c/0x5c
[65731.260227] [T32454] el1h_64_sync_handler+0x54/0x90
[65731.260248] [T32454] el1h_64_sync+0x68/0x6c
[65731.260269] [T32454] z_erofs_decompress_queue+0x7f0/0x2258
--> be->decompressed_pages = kvcalloc(be->nr_pages, sizeof(struct page *), GFP_KERNEL | __GFP_NOFAIL);
kernel panic by NULL pointer dereference.
erofs assume kvmalloc with __GFP_NOFAIL never return NULL.
[65731.260293] [T32454] z_erofs_runqueue+0xf30/0x104c
[65731.260314] [T32454] z_erofs_readahead+0x4f0/0x968
[65731.260339] [T32454] read_pages+0x170/0xadc
[65731.260364] [T32454] page_cache_ra_unbounded+0x874/0xf30
[65731.260388] [T32454] page_cache_ra_order+0x24c/0x714
[65731.260411] [T32454] filemap_fault+0xbf0/0x1a74
[65731.260437] [T32454] __do_fault+0xd0/0x33c
[65731.260462] [T32454] handle_mm_fault+0xf74/0x3fe0
[65731.260486] [T32454] do_mem_abort+0x54c/0x1b34
[65731.260509] [T32454] el0_da+0x44/0x94
[65731.260531] [T32454] el0t_64_sync_handler+0x98/0xb4
[65731.260553] [T32454] el0t_64_sync+0x198/0x19c
Link: https://lkml.kernel.org/r/20240510100131.1865-1-hailong.liu@oppo.com
Fixes: 9376130c390a ("mm/vmalloc: add support for __GFP_NOFAIL")
Signed-off-by: Hailong.Liu <hailong.liu@oppo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Barry Song <21cnbao@gmail.com>
Reported-by: Oven <liyangouwen1@oppo.com>
Reviewed-by: Barry Song <baohua@kernel.org>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Gao Xiang <xiang@kernel.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull mm updates from Andrew Morton:
"The usual shower of singleton fixes and minor series all over MM,
documented (hopefully adequately) in the respective changelogs.
Notable series include:
- Lucas Stach has provided some page-mapping cleanup/consolidation/
maintainability work in the series "mm/treewide: Remove pXd_huge()
API".
- In the series "Allow migrate on protnone reference with
MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
MPOL_PREFERRED_MANY mode, yielding almost doubled performance in
one test.
- In their series "Memory allocation profiling" Kent Overstreet and
Suren Baghdasaryan have contributed a means of determining (via
/proc/allocinfo) whereabouts in the kernel memory is being
allocated: number of calls and amount of memory.
- Matthew Wilcox has provided the series "Various significant MM
patches" which does a number of rather unrelated things, but in
largely similar code sites.
- In his series "mm: page_alloc: freelist migratetype hygiene"
Johannes Weiner has fixed the page allocator's handling of
migratetype requests, with resulting improvements in compaction
efficiency.
- In the series "make the hugetlb migration strategy consistent"
Baolin Wang has fixed a hugetlb migration issue, which should
improve hugetlb allocation reliability.
- Liu Shixin has hit an I/O meltdown caused by readahead in a
memory-tight memcg. Addressed in the series "Fix I/O high when
memory almost met memcg limit".
- In the series "mm/filemap: optimize folio adding and splitting"
Kairui Song has optimized pagecache insertion, yielding ~10%
performance improvement in one test.
- Baoquan He has cleaned up and consolidated the early zone
initialization code in the series "mm/mm_init.c: refactor
free_area_init_core()".
- Baoquan has also redone some MM initializatio code in the series
"mm/init: minor clean up and improvement".
- MM helper cleanups from Christoph Hellwig in his series "remove
follow_pfn".
- More cleanups from Matthew Wilcox in the series "Various
page->flags cleanups".
- Vlastimil Babka has contributed maintainability improvements in the
series "memcg_kmem hooks refactoring".
- More folio conversions and cleanups in Matthew Wilcox's series:
"Convert huge_zero_page to huge_zero_folio"
"khugepaged folio conversions"
"Remove page_idle and page_young wrappers"
"Use folio APIs in procfs"
"Clean up __folio_put()"
"Some cleanups for memory-failure"
"Remove page_mapping()"
"More folio compat code removal"
- David Hildenbrand chipped in with "fs/proc/task_mmu: convert
hugetlb functions to work on folis".
- Code consolidation and cleanup work related to GUP's handling of
hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
- Rick Edgecombe has developed some fixes to stack guard gaps in the
series "Cover a guard gap corner case".
- Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the
series "mm/ksm: fix ksm exec support for prctl".
- Baolin Wang has implemented NUMA balancing for multi-size THPs.
This is a simple first-cut implementation for now. The series is
"support multi-size THP numa balancing".
- Cleanups to vma handling helper functions from Matthew Wilcox in
the series "Unify vma_address and vma_pgoff_address".
- Some selftests maintenance work from Dev Jain in the series
"selftests/mm: mremap_test: Optimizations and style fixes".
- Improvements to the swapping of multi-size THPs from Ryan Roberts
in the series "Swap-out mTHP without splitting".
- Kefeng Wang has significantly optimized the handling of arm64's
permission page faults in the series
"arch/mm/fault: accelerate pagefault when badaccess"
"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
- GUP cleanups from David Hildenbrand in "mm/gup: consistently call
it GUP-fast".
- hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault
path to use struct vm_fault".
- selftests build fixes from John Hubbard in the series "Fix
selftests/mm build without requiring "make headers"".
- Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
series "Improved Memory Tier Creation for CPUless NUMA Nodes".
Fixes the initialization code so that migration between different
memory types works as intended.
- David Hildenbrand has improved follow_pte() and fixed an errant
driver in the series "mm: follow_pte() improvements and acrn
follow_pte() fixes".
- David also did some cleanup work on large folio mapcounts in his
series "mm: mapcount for large folios + page_mapcount() cleanups".
- Folio conversions in KSM in Alex Shi's series "transfer page to
folio in KSM".
- Barry Song has added some sysfs stats for monitoring multi-size
THP's in the series "mm: add per-order mTHP alloc and swpout
counters".
- Some zswap cleanups from Yosry Ahmed in the series "zswap
same-filled and limit checking cleanups".
- Matthew Wilcox has been looking at buffer_head code and found the
documentation to be lacking. The series is "Improve buffer head
documentation".
- Multi-size THPs get more work, this time from Lance Yang. His
series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free"
optimizes the freeing of these things.
- Kemeng Shi has added more userspace-visible writeback
instrumentation in the series "Improve visibility of writeback".
- Kemeng Shi then sent some maintenance work on top in the series
"Fix and cleanups to page-writeback".
- Matthew Wilcox reduces mmap_lock traffic in the anon vma code in
the series "Improve anon_vma scalability for anon VMAs". Intel's
test bot reported an improbable 3x improvement in one test.
- SeongJae Park adds some DAMON feature work in the series
"mm/damon: add a DAMOS filter type for page granularity access recheck"
"selftests/damon: add DAMOS quota goal test"
- Also some maintenance work in the series
"mm/damon/paddr: simplify page level access re-check for pageout"
"mm/damon: misc fixes and improvements"
- David Hildenbrand has disabled some known-to-fail selftests ni the
series "selftests: mm: cow: flag vmsplice() hugetlb tests as
XFAIL".
- memcg metadata storage optimizations from Shakeel Butt in "memcg:
reduce memory consumption by memcg stats".
- DAX fixes and maintenance work from Vishal Verma in the series
"dax/bus.c: Fixups for dax-bus locking""
* tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits)
memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order
selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault
selftests: cgroup: add tests to verify the zswap writeback path
mm: memcg: make alloc_mem_cgroup_per_node_info() return bool
mm/damon/core: fix return value from damos_wmark_metric_value
mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED
selftests: cgroup: remove redundant enabling of memory controller
Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree
Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT
Docs/mm/damon/design: use a list for supported filters
Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command
Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file
selftests/damon: classify tests for functionalities and regressions
selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'
selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts
selftests/damon/_damon_sysfs: check errors from nr_schemes file reads
mm/damon/core: initialize ->esz_bp from damos_quota_init_priv()
selftests/damon: add a test for DAMOS quota goal
...
|
|
In vmap_pte_range, BUG_ON is called when page is already mapped,
It doesn't give enough information to debug further.
Dumping page owner information alongwith BUG_ON will be more useful
in case of multiple page mapping.
Example:
[ 14.552875] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10b923
[ 14.553440] flags: 0xbffff0000000000(node=0|zone=2|lastcpupid=0x3ffff)
[ 14.554001] page_type: 0xffffffff()
[ 14.554783] raw: 0bffff0000000000 0000000000000000 dead000000000122 0000000000000000
[ 14.555230] raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
[ 14.555768] page dumped because: remapping already mapped page
[ 14.556172] page_owner tracks the page as allocated
[ 14.556482] page last allocated via order 0, migratetype Unmovable, gfp_mask 0xcc0(GFP_KERNEL), pid 80, tgid 80 (insmod), ts 14552004992, free_ts 0
[ 14.557286] prep_new_page+0xa8/0x10c
[ 14.558052] get_page_from_freelist+0x7f8/0x1248
[ 14.558298] __alloc_pages+0x164/0x2b4
[ 14.558514] alloc_pages_mpol+0x88/0x230
[ 14.558904] alloc_pages+0x4c/0x7c
[ 14.559157] load_module+0x74/0x1af4
[ 14.559361] __do_sys_init_module+0x190/0x1fc
[ 14.559615] __arm64_sys_init_module+0x1c/0x28
[ 14.559883] invoke_syscall+0x44/0x108
[ 14.560109] el0_svc_common.constprop.0+0x40/0xe0
[ 14.560371] do_el0_svc_compat+0x1c/0x34
[ 14.560600] el0_svc_compat+0x2c/0x80
[ 14.560820] el0t_32_sync_handler+0x90/0x140
[ 14.561040] el0t_32_sync+0x194/0x198
[ 14.561329] page_owner free stack trace missing
[ 14.562049] ------------[ cut here ]------------
[ 14.562314] kernel BUG at mm/vmalloc.c:113!
Link: https://lkml.kernel.org/r/20240424111838.3782931-2-hariom1.p@samsung.com
Signed-off-by: Hariom Panthi <hariom1.p@samsung.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Maninder Singh <maninder1.s@samsung.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Rohit Thapliyal <r.thapliyal@samsung.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
