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2025-05-31Merge tag 'mm-nonmm-stable-2025-05-31-15-28' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - "hung_task: extend blocking task stacktrace dump to semaphore" from Lance Yang enhances the hung task detector. The detector presently dumps the blocking tasks's stack when it is blocked on a mutex. Lance's series extends this to semaphores - "nilfs2: improve sanity checks in dirty state propagation" from Wentao Liang addresses a couple of minor flaws in nilfs2 - "scripts/gdb: Fixes related to lx_per_cpu()" from Illia Ostapyshyn fixes a couple of issues in the gdb scripts - "Support kdump with LUKS encryption by reusing LUKS volume keys" from Coiby Xu addresses a usability problem with kdump. When the dump device is LUKS-encrypted, the kdump kernel may not have the keys to the encrypted filesystem. A full writeup of this is in the series [0/N] cover letter - "sysfs: add counters for lockups and stalls" from Max Kellermann adds /sys/kernel/hardlockup_count and /sys/kernel/hardlockup_count and /sys/kernel/rcu_stall_count - "fork: Page operation cleanups in the fork code" from Pasha Tatashin implements a number of code cleanups in fork.c - "scripts/gdb/symbols: determine KASLR offset on s390 during early boot" from Ilya Leoshkevich fixes some s390 issues in the gdb scripts * tag 'mm-nonmm-stable-2025-05-31-15-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (67 commits) llist: make llist_add_batch() a static inline delayacct: remove redundant code and adjust indentation squashfs: add optional full compressed block caching crash_dump, nvme: select CONFIGFS_FS as built-in scripts/gdb/symbols: determine KASLR offset on s390 during early boot scripts/gdb/symbols: factor out pagination_off() scripts/gdb/symbols: factor out get_vmlinux() kernel/panic.c: format kernel-doc comments mailmap: update and consolidate Casey Connolly's name and email nilfs2: remove wbc->for_reclaim handling fork: define a local GFP_VMAP_STACK fork: check charging success before zeroing stack fork: clean-up naming of vm_stack/vm_struct variables in vmap stacks code fork: clean-up ifdef logic around stack allocation kernel/rcu/tree_stall: add /sys/kernel/rcu_stall_count kernel/watchdog: add /sys/kernel/{hard,soft}lockup_count x86/crash: make the page that stores the dm crypt keys inaccessible x86/crash: pass dm crypt keys to kdump kernel Revert "x86/mm: Remove unused __set_memory_prot()" crash_dump: retrieve dm crypt keys in kdump kernel ...
2025-05-31Merge tag 'mm-stable-2025-05-31-14-50' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "Add folio_mk_pte()" from Matthew Wilcox simplifies the act of creating a pte which addresses the first page in a folio and reduces the amount of plumbing which architecture must implement to provide this. - "Misc folio patches for 6.16" from Matthew Wilcox is a shower of largely unrelated folio infrastructure changes which clean things up and better prepare us for future work. - "memory,x86,acpi: hotplug memory alignment advisement" from Gregory Price adds early-init code to prevent x86 from leaving physical memory unused when physical address regions are not aligned to memory block size. - "mm/compaction: allow more aggressive proactive compaction" from Michal Clapinski provides some tuning of the (sadly, hard-coded (more sadly, not auto-tuned)) thresholds for our invokation of proactive compaction. In a simple test case, the reduction of a guest VM's memory consumption was dramatic. - "Minor cleanups and improvements to swap freeing code" from Kemeng Shi provides some code cleaups and a small efficiency improvement to this part of our swap handling code. - "ptrace: introduce PTRACE_SET_SYSCALL_INFO API" from Dmitry Levin adds the ability for a ptracer to modify syscalls arguments. At this time we can alter only "system call information that are used by strace system call tampering, namely, syscall number, syscall arguments, and syscall return value. This series should have been incorporated into mm.git's "non-MM" branch, but I goofed. - "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions" from Andrei Vagin extends the info returned by the PAGEMAP_SCAN ioctl against /proc/pid/pagemap. This permits CRIU to more efficiently get at the info about guard regions. - "Fix parameter passed to page_mapcount_is_type()" from Gavin Shan implements that fix. No runtime effect is expected because validate_page_before_insert() happens to fix up this error. - "kernel/events/uprobes: uprobe_write_opcode() rewrite" from David Hildenbrand basically brings uprobe text poking into the current decade. Remove a bunch of hand-rolled implementation in favor of using more current facilities. - "mm/ptdump: Drop assumption that pxd_val() is u64" from Anshuman Khandual provides enhancements and generalizations to the pte dumping code. This might be needed when 128-bit Page Table Descriptors are enabled for ARM. - "Always call constructor for kernel page tables" from Kevin Brodsky ensures that the ctor/dtor is always called for kernel pgtables, as it already is for user pgtables. This permits the addition of more functionality such as "insert hooks to protect page tables". This change does result in various architectures performing unnecesary work, but this is fixed up where it is anticipated to occur. - "Rust support for mm_struct, vm_area_struct, and mmap" from Alice Ryhl adds plumbing to permit Rust access to core MM structures. - "fix incorrectly disallowed anonymous VMA merges" from Lorenzo Stoakes takes advantage of some VMA merging opportunities which we've been missing for 15 years. - "mm/madvise: batch tlb flushes for MADV_DONTNEED and MADV_FREE" from SeongJae Park optimizes process_madvise()'s TLB flushing. Instead of flushing each address range in the provided iovec, we batch the flushing across all the iovec entries. The syscall's cost was approximately halved with a microbenchmark which was designed to load this particular operation. - "Track node vacancy to reduce worst case allocation counts" from Sidhartha Kumar makes the maple tree smarter about its node preallocation. stress-ng mmap performance increased by single-digit percentages and the amount of unnecessarily preallocated memory was dramaticelly reduced. - "mm/gup: Minor fix, cleanup and improvements" from Baoquan He removes a few unnecessary things which Baoquan noted when reading the code. - ""Enhance sysfs handling for memory hotplug in weighted interleave" from Rakie Kim "enhances the weighted interleave policy in the memory management subsystem by improving sysfs handling, fixing memory leaks, and introducing dynamic sysfs updates for memory hotplug support". Fixes things on error paths which we are unlikely to hit. - "mm/damon: auto-tune DAMOS for NUMA setups including tiered memory" from SeongJae Park introduces new DAMOS quota goal metrics which eliminate the manual tuning which is required when utilizing DAMON for memory tiering. - "mm/vmalloc.c: code cleanup and improvements" from Baoquan He provides cleanups and small efficiency improvements which Baoquan found via code inspection. - "vmscan: enforce mems_effective during demotion" from Gregory Price changes reclaim to respect cpuset.mems_effective during demotion when possible. because presently, reclaim explicitly ignores cpuset.mems_effective when demoting, which may cause the cpuset settings to violated. This is useful for isolating workloads on a multi-tenant system from certain classes of memory more consistently. - "Clean up split_huge_pmd_locked() and remove unnecessary folio pointers" from Gavin Guo provides minor cleanups and efficiency gains in in the huge page splitting and migrating code. - "Use kmem_cache for memcg alloc" from Huan Yang creates a slab cache for `struct mem_cgroup', yielding improved memory utilization. - "add max arg to swappiness in memory.reclaim and lru_gen" from Zhongkun He adds a new "max" argument to the "swappiness=" argument for memory.reclaim MGLRU's lru_gen. This directs proactive reclaim to reclaim from only anon folios rather than file-backed folios. - "kexec: introduce Kexec HandOver (KHO)" from Mike Rapoport is the first step on the path to permitting the kernel to maintain existing VMs while replacing the host kernel via file-based kexec. At this time only memblock's reserve_mem is preserved. - "mm: Introduce for_each_valid_pfn()" from David Woodhouse provides and uses a smarter way of looping over a pfn range. By skipping ranges of invalid pfns. - "sched/numa: Skip VMA scanning on memory pinned to one NUMA node via cpuset.mems" from Libo Chen removes a lot of pointless VMA scanning when a task is pinned a single NUMA mode. Dramatic performance benefits were seen in some real world cases. - "JFS: Implement migrate_folio for jfs_metapage_aops" from Shivank Garg addresses a warning which occurs during memory compaction when using JFS. - "move all VMA allocation, freeing and duplication logic to mm" from Lorenzo Stoakes moves some VMA code from kernel/fork.c into the more appropriate mm/vma.c. - "mm, swap: clean up swap cache mapping helper" from Kairui Song provides code consolidation and cleanups related to the folio_index() function. - "mm/gup: Cleanup memfd_pin_folios()" from Vishal Moola does that. - "memcg: Fix test_memcg_min/low test failures" from Waiman Long addresses some bogus failures which are being reported by the test_memcontrol selftest. - "eliminate mmap() retry merge, add .mmap_prepare hook" from Lorenzo Stoakes commences the deprecation of file_operations.mmap() in favor of the new file_operations.mmap_prepare(). The latter is more restrictive and prevents drivers from messing with things in ways which, amongst other problems, may defeat VMA merging. - "memcg: decouple memcg and objcg stocks"" from Shakeel Butt decouples the per-cpu memcg charge cache from the objcg's one. This is a step along the way to making memcg and objcg charging NMI-safe, which is a BPF requirement. - "mm/damon: minor fixups and improvements for code, tests, and documents" from SeongJae Park is yet another batch of miscellaneous DAMON changes. Fix and improve minor problems in code, tests and documents. - "memcg: make memcg stats irq safe" from Shakeel Butt converts memcg stats to be irq safe. Another step along the way to making memcg charging and stats updates NMI-safe, a BPF requirement. - "Let unmap_hugepage_range() and several related functions take folio instead of page" from Fan Ni provides folio conversions in the hugetlb code. * tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (285 commits) mm: pcp: increase pcp->free_count threshold to trigger free_high mm/hugetlb: convert use of struct page to folio in __unmap_hugepage_range() mm/hugetlb: refactor __unmap_hugepage_range() to take folio instead of page mm/hugetlb: refactor unmap_hugepage_range() to take folio instead of page mm/hugetlb: pass folio instead of page to unmap_ref_private() memcg: objcg stock trylock without irq disabling memcg: no stock lock for cpu hot-unplug memcg: make __mod_memcg_lruvec_state re-entrant safe against irqs memcg: make count_memcg_events re-entrant safe against irqs memcg: make mod_memcg_state re-entrant safe against irqs memcg: move preempt disable to callers of memcg_rstat_updated memcg: memcg_rstat_updated re-entrant safe against irqs mm: khugepaged: decouple SHMEM and file folios' collapse selftests/eventfd: correct test name and improve messages alloc_tag: check mem_profiling_support in alloc_tag_init Docs/damon: update titles and brief introductions to explain DAMOS selftests/damon/_damon_sysfs: read tried regions directories in order mm/damon/tests/core-kunit: add a test for damos_set_filters_default_reject() mm/damon/paddr: remove unused variable, folio_list, in damon_pa_stat() mm/damon/sysfs-schemes: fix wrong comment on damons_sysfs_quota_goal_metric_strs ...
2025-05-21kexec_file: allow to place kexec_buf randomlyCoiby Xu
Patch series "Support kdump with LUKS encryption by reusing LUKS volume keys", v9. LUKS is the standard for Linux disk encryption, widely adopted by users, and in some cases, such as Confidential VMs, it is a requirement. With kdump enabled, when the first kernel crashes, the system can boot into the kdump/crash kernel to dump the memory image (i.e., /proc/vmcore) to a specified target. However, there are two challenges when dumping vmcore to a LUKS-encrypted device: - Kdump kernel may not be able to decrypt the LUKS partition. For some machines, a system administrator may not have a chance to enter the password to decrypt the device in kdump initramfs after the 1st kernel crashes; For cloud confidential VMs, depending on the policy the kdump kernel may not be able to unseal the keys with TPM and the console virtual keyboard is untrusted. - LUKS2 by default use the memory-hard Argon2 key derivation function which is quite memory-consuming compared to the limited memory reserved for kdump. Take Fedora example, by default, only 256M is reserved for systems having memory between 4G-64G. With LUKS enabled, ~1300M needs to be reserved for kdump. Note if the memory reserved for kdump can't be used by 1st kernel i.e. an user sees ~1300M memory missing in the 1st kernel. Besides users (at least for Fedora) usually expect kdump to work out of the box i.e. no manual password input or custom crashkernel value is needed. And it doesn't make sense to derivate the keys again in kdump kernel which seems to be redundant work. This patchset addresses the above issues by making the LUKS volume keys persistent for kdump kernel with the help of cryptsetup's new APIs (--link-vk-to-keyring/--volume-key-keyring). Here is the life cycle of the kdump copies of LUKS volume keys, 1. After the 1st kernel loads the initramfs during boot, systemd use an user-input passphrase to de-crypt the LUKS volume keys or TPM-sealed key and then save the volume keys to specified keyring (using the --link-vk-to-keyring API) and the key will expire within specified time. 2. A user space tool (kdump initramfs loader like kdump-utils) create key items inside /sys/kernel/config/crash_dm_crypt_keys to inform the 1st kernel which keys are needed. 3. When the kdump initramfs is loaded by the kexec_file_load syscall, the 1st kernel will iterate created key items, save the keys to kdump reserved memory. 4. When the 1st kernel crashes and the kdump initramfs is booted, the kdump initramfs asks the kdump kernel to create a user key using the key stored in kdump reserved memory by writing yes to /sys/kernel/crash_dm_crypt_keys/restore. Then the LUKS encrypted device is unlocked with libcryptsetup's --volume-key-keyring API. 5. The system gets rebooted to the 1st kernel after dumping vmcore to the LUKS encrypted device is finished After libcryptsetup saving the LUKS volume keys to specified keyring, whoever takes this should be responsible for the safety of these copies of keys. The keys will be saved in the memory area exclusively reserved for kdump where even the 1st kernel has no direct access. And further more, two additional protections are added, - save the copy randomly in kdump reserved memory as suggested by Jan - clear the _PAGE_PRESENT flag of the page that stores the copy as suggested by Pingfan This patchset only supports x86. There will be patches to support other architectures once this patch set gets merged. This patch (of 9): Currently, kexec_buf is placed in order which means for the same machine, the info in the kexec_buf is always located at the same position each time the machine is booted. This may cause a risk for sensitive information like LUKS volume key. Now struct kexec_buf has a new field random which indicates it's supposed to be placed in a random position. Note this feature is enabled only when CONFIG_CRASH_DUMP is enabled. So it only takes effect for kdump and won't impact kexec reboot. Link: https://lkml.kernel.org/r/20250502011246.99238-1-coxu@redhat.com Link: https://lkml.kernel.org/r/20250502011246.99238-2-coxu@redhat.com Signed-off-by: Coiby Xu <coxu@redhat.com> Suggested-by: Jan Pazdziora <jpazdziora@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: "Daniel P. Berrange" <berrange@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: Liu Pingfan <kernelfans@gmail.com> Cc: Milan Broz <gmazyland@gmail.com> Cc: Ondrej Kozina <okozina@redhat.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12kexec: add KHO support to kexec file loadsAlexander Graf
Kexec has 2 modes: A user space driven mode and a kernel driven mode. For the kernel driven mode, kernel code determines the physical addresses of all target buffers that the payload gets copied into. With KHO, we can only safely copy payloads into the "scratch area". Teach the kexec file loader about it, so it only allocates for that area. In addition, enlighten it with support to ask the KHO subsystem for its respective payloads to copy into target memory. Also teach the KHO subsystem how to fill the images for file loads. Link: https://lkml.kernel.org/r/20250509074635.3187114-8-changyuanl@google.com Signed-off-by: Alexander Graf <graf@amazon.com> Co-developed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Co-developed-by: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Changyuan Lyu <changyuanl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Anthony Yznaga <anthony.yznaga@oracle.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ashish Kalra <ashish.kalra@amd.com> Cc: Ben Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Gowans <jgowans@amazon.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pratyush Yadav <ptyadav@amazon.de> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11kexec_file: use SHA-256 library API instead of crypto_shash APIEric Biggers
This user of SHA-256 does not support any other algorithm, so the crypto_shash abstraction provides no value. Just use the SHA-256 library API instead, which is much simpler and easier to use. Tested with '/sbin/kexec --kexec-file-syscall'. Link: https://lkml.kernel.org/r/20250428185721.844686-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Young <dyoung@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-04-29ima: kexec: move IMA log copy from kexec load to executeSteven Chen
The IMA log is currently copied to the new kernel during kexec 'load' using ima_dump_measurement_list(). However, the IMA measurement list copied at kexec 'load' may result in loss of IMA measurements records that only occurred after the kexec 'load'. Move the IMA measurement list log copy from kexec 'load' to 'execute' Make the kexec_segment_size variable a local static variable within the file, so it can be accessed during both kexec 'load' and 'execute'. Define kexec_post_load() as a wrapper for calling ima_kexec_post_load() and machine_kexec_post_load(). Replace the existing direct call to machine_kexec_post_load() with kexec_post_load(). When there is insufficient memory to copy all the measurement logs, copy as much of the measurement list as possible. Co-developed-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Young <dyoung@redhat.com> Signed-off-by: Steven Chen <chenste@linux.microsoft.com> Tested-by: Stefan Berger <stefanb@linux.ibm.com> # ppc64/kvm Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2025-04-29ima: kexec: skip IMA segment validation after kexec soft rebootSteven Chen
Currently, the function kexec_calculate_store_digests() calculates and stores the digest of the segment during the kexec_file_load syscall, where the IMA segment is also allocated. Later, the IMA segment will be updated with the measurement log at the kexec execute stage when a kexec reboot is initiated. Therefore, the digests should be updated for the IMA segment in the normal case. The problem is that the content of memory segments carried over to the new kernel during the kexec systemcall can be changed at kexec 'execute' stage, but the size and the location of the memory segments cannot be changed at kexec 'execute' stage. To address this, skip the calculation and storage of the digest for the IMA segment in kexec_calculate_store_digests() so that it is not added to the purgatory_sha_regions. With this change, the IMA segment is not included in the digest calculation, storage, and verification. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Young <dyoung@redhat.com> Co-developed-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Signed-off-by: Steven Chen <chenste@linux.microsoft.com> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Acked-by: Baoquan He <bhe@redhat.com> Tested-by: Stefan Berger <stefanb@linux.ibm.com> # ppc64/kvm [zohar@linux.ibm.com: Fixed Signed-off-by tag to match author's email ] Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2025-03-16crash: let arch decide usable memory range in reserved areaSourabh Jain
Although the crashkernel area is reserved, on architectures like PowerPC, it is possible for the crashkernel reserved area to contain components like RTAS, TCE, OPAL, etc. To avoid placing kexec segments over these components, PowerPC has its own set of APIs to locate holes in the crashkernel reserved area. Add an arch hook in the generic locate mem hole APIs so that architectures can handle such special regions in the crashkernel area while locating memory holes for kexec segments using generic APIs. With this, a lot of redundant arch-specific code can be removed, as it performs the exact same job as the generic APIs. To keep the generic and arch-specific changes separate, the changes related to moving PowerPC to use the generic APIs and the removal of PowerPC-specific APIs for memory hole allocation are done in a subsequent patch titled "powerpc/crash: Use generic APIs to locate memory hole for kdump. Link: https://lkml.kernel.org/r/20250131113830.925179-4-sourabhjain@linux.ibm.com Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01kexec_file: fix elfcorehdr digest exclusion when CONFIG_CRASH_HOTPLUG=yPetr Tesarik
Fix the condition to exclude the elfcorehdr segment from the SHA digest calculation. The j iterator is an index into the output sha_regions[] array, not into the input image->segment[] array. Once it reaches image->elfcorehdr_index, all subsequent segments are excluded. Besides, if the purgatory segment precedes the elfcorehdr segment, the elfcorehdr may be wrongly included in the calculation. Link: https://lkml.kernel.org/r/20240805150750.170739-1-petr.tesarik@suse.com Fixes: f7cc804a9fd4 ("kexec: exclude elfcorehdr from the segment digest") Signed-off-by: Petr Tesarik <ptesarik@suse.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Sourabh Jain <sourabhjain@linux.ibm.com> Cc: Eric DeVolder <eric_devolder@yahoo.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-23crash: add a new kexec flag for hotplug supportSourabh Jain
Commit a72bbec70da2 ("crash: hotplug support for kexec_load()") introduced a new kexec flag, `KEXEC_UPDATE_ELFCOREHDR`. Kexec tool uses this flag to indicate to the kernel that it is safe to modify the elfcorehdr of the kdump image loaded using the kexec_load system call. However, it is possible that architectures may need to update kexec segments other then elfcorehdr. For example, FDT (Flatten Device Tree) on PowerPC. Introducing a new kexec flag for every new kexec segment may not be a good solution. Hence, a generic kexec flag bit, `KEXEC_CRASH_HOTPLUG_SUPPORT`, is introduced to share the CPU/Memory hotplug support intent between the kexec tool and the kernel for the kexec_load system call. Now we have two kexec flags that enables crash hotplug support for kexec_load system call. First is KEXEC_UPDATE_ELFCOREHDR (only used in x86), and second is KEXEC_CRASH_HOTPLUG_SUPPORT (for all architectures). To simplify the process of finding and reporting the crash hotplug support the following changes are introduced. 1. Define arch specific function to process the kexec flags and determine crash hotplug support 2. Rename the @update_elfcorehdr member of struct kimage to @hotplug_support and populate it for both kexec_load and kexec_file_load syscalls, because architecture can update more than one kexec segment 3. Let generic function crash_check_hotplug_support report hotplug support for loaded kdump image based on value of @hotplug_support To bring the x86 crash hotplug support in line with the above points, the following changes have been made: - Introduce the arch_crash_hotplug_support function to process kexec flags and determine crash hotplug support - Remove the arch_crash_hotplug_[cpu|memory]_support functions Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com> Acked-by: Baoquan He <bhe@redhat.com> Acked-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240326055413.186534-3-sourabhjain@linux.ibm.com
2024-02-23arm64, crash: wrap crash dumping code into crash related ifdefsBaoquan He
Now crash codes under kernel/ folder has been split out from kexec code, crash dumping can be separated from kexec reboot in config items on arm64 with some adjustments. Here wrap up crash dumping codes with CONFIG_CRASH_DUMP ifdeffery. [bhe@redhat.com: fix building error in generic codes] Link: https://lkml.kernel.org/r/20240129135033.157195-2-bhe@redhat.com Link: https://lkml.kernel.org/r/20240124051254.67105-8-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Pingfan Liu <piliu@redhat.com> Cc: Klara Modin <klarasmodin@gmail.com> Cc: Michael Kelley <mhklinux@outlook.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23crash: split crash dumping code out from kexec_core.cBaoquan He
Currently, KEXEC_CORE select CRASH_CORE automatically because crash codes need be built in to avoid compiling error when building kexec code even though the crash dumping functionality is not enabled. E.g -------------------- CONFIG_CRASH_CORE=y CONFIG_KEXEC_CORE=y CONFIG_KEXEC=y CONFIG_KEXEC_FILE=y --------------------- After splitting out crashkernel reservation code and vmcoreinfo exporting code, there's only crash related code left in kernel/crash_core.c. Now move crash related codes from kexec_core.c to crash_core.c and only build it in when CONFIG_CRASH_DUMP=y. And also wrap up crash codes inside CONFIG_CRASH_DUMP ifdeffery scope, or replace inappropriate CONFIG_KEXEC_CORE ifdef with CONFIG_CRASH_DUMP ifdef in generic kernel files. With these changes, crash_core codes are abstracted from kexec codes and can be disabled at all if only kexec reboot feature is wanted. Link: https://lkml.kernel.org/r/20240124051254.67105-5-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Pingfan Liu <piliu@redhat.com> Cc: Klara Modin <klarasmodin@gmail.com> Cc: Michael Kelley <mhklinux@outlook.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29kexec_file: fix incorrect temp_start value in locate_mem_hole_top_down()Yuntao Wang
temp_end represents the address of the last available byte. Therefore, the starting address of the memory segment with temp_end as its last available byte and a size of `kbuf->memsz`, that is, the value of temp_start, should be `temp_end - kbuf->memsz + 1` instead of `temp_end - kbuf->memsz`. Additionally, use the ALIGN_DOWN macro instead of open-coding it directly in locate_mem_hole_top_down() to improve code readability. Link: https://lkml.kernel.org/r/20231217033528.303333-3-ytcoode@gmail.com Signed-off-by: Yuntao Wang <ytcoode@gmail.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-20kexec_file: print out debugging message if requiredBaoquan He
Then when specifying '-d' for kexec_file_load interface, loaded locations of kernel/initrd/cmdline etc can be printed out to help debug. Here replace pr_debug() with the newly added kexec_dprintk() in kexec_file loading related codes. And also print out type/start/head of kimage and flags to help debug. Link: https://lkml.kernel.org/r/20231213055747.61826-3-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Conor Dooley <conor@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-20kexec_file: add kexec_file flag to control debug printingBaoquan He
Patch series "kexec_file: print out debugging message if required", v4. Currently, specifying '-d' on kexec command will print a lot of debugging informationabout kexec/kdump loading with kexec_load interface. However, kexec_file_load prints nothing even though '-d' is specified. It's very inconvenient to debug or analyze the kexec/kdump loading when something wrong happened with kexec/kdump itself or develper want to check the kexec/kdump loading. In this patchset, a kexec_file flag is KEXEC_FILE_DEBUG added and checked in code. If it's passed in, debugging message of kexec_file code will be printed out and can be seen from console and dmesg. Otherwise, the debugging message is printed like beofre when pr_debug() is taken. Note: **** ===== 1) The code in kexec-tools utility also need be changed to support passing KEXEC_FILE_DEBUG to kernel when 'kexec -s -d' is specified. The patch link is here: ========= [PATCH] kexec_file: add kexec_file flag to support debug printing http://lists.infradead.org/pipermail/kexec/2023-November/028505.html 2) s390 also has kexec_file code, while I am not sure what debugging information is necessary. So leave it to s390 developer. Test: **** ==== Testing was done in v1 on x86_64 and arm64. For v4, tested on x86_64 again. And on x86_64, the printed messages look like below: -------------------------------------------------------------- kexec measurement buffer for the loaded kernel at 0x207fffe000. Loaded purgatory at 0x207fff9000 Loaded boot_param, command line and misc at 0x207fff3000 bufsz=0x1180 memsz=0x1180 Loaded 64bit kernel at 0x207c000000 bufsz=0xc88200 memsz=0x3c4a000 Loaded initrd at 0x2079e79000 bufsz=0x2186280 memsz=0x2186280 Final command line is: root=/dev/mapper/fedora_intel--knightslanding--lb--02-root ro rd.lvm.lv=fedora_intel-knightslanding-lb-02/root console=ttyS0,115200N81 crashkernel=256M E820 memmap: 0000000000000000-000000000009a3ff (1) 000000000009a400-000000000009ffff (2) 00000000000e0000-00000000000fffff (2) 0000000000100000-000000006ff83fff (1) 000000006ff84000-000000007ac50fff (2) ...... 000000207fff6150-000000207fff615f (128) 000000207fff6160-000000207fff714f (1) 000000207fff7150-000000207fff715f (128) 000000207fff7160-000000207fff814f (1) 000000207fff8150-000000207fff815f (128) 000000207fff8160-000000207fffffff (1) nr_segments = 5 segment[0]: buf=0x000000004e5ece74 bufsz=0x211 mem=0x207fffe000 memsz=0x1000 segment[1]: buf=0x000000009e871498 bufsz=0x4000 mem=0x207fff9000 memsz=0x5000 segment[2]: buf=0x00000000d879f1fe bufsz=0x1180 mem=0x207fff3000 memsz=0x2000 segment[3]: buf=0x000000001101cd86 bufsz=0xc88200 mem=0x207c000000 memsz=0x3c4a000 segment[4]: buf=0x00000000c6e38ac7 bufsz=0x2186280 mem=0x2079e79000 memsz=0x2187000 kexec_file_load: type:0, start:0x207fff91a0 head:0x109e004002 flags:0x8 --------------------------------------------------------------------------- This patch (of 7): When specifying 'kexec -c -d', kexec_load interface will print loading information, e.g the regions where kernel/initrd/purgatory/cmdline are put, the memmap passed to 2nd kernel taken as system RAM ranges, and printing all contents of struct kexec_segment, etc. These are very helpful for analyzing or positioning what's happening when kexec/kdump itself failed. The debugging printing for kexec_load interface is made in user space utility kexec-tools. Whereas, with kexec_file_load interface, 'kexec -s -d' print nothing. Because kexec_file code is mostly implemented in kernel space, and the debugging printing functionality is missed. It's not convenient when debugging kexec/kdump loading and jumping with kexec_file_load interface. Now add KEXEC_FILE_DEBUG to kexec_file flag to control the debugging message printing. And add global variable kexec_file_dbg_print and macro kexec_dprintk() to facilitate the printing. This is a preparation, later kexec_dprintk() will be used to replace the existing pr_debug(). Once 'kexec -s -d' is specified, it will print out kexec/kdump loading information. If '-d' is not specified, it regresses to pr_debug(). Link: https://lkml.kernel.org/r/20231213055747.61826-1-bhe@redhat.com Link: https://lkml.kernel.org/r/20231213055747.61826-2-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Conor Dooley <conor@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10kexec_file: load kernel at top of system RAM if requiredBaoquan He
Patch series "kexec_file: Load kernel at top of system RAM if required". Justification: ============== Kexec_load interface has been doing top down searching and loading kernel/initrd/purgtory etc to prepare for kexec reboot. In that way, the benefits are that it avoids to consume and fragment limited low memory which satisfy DMA buffer allocation and big chunk of continuous memory during system init; and avoids to stir with BIOS/FW reserved or occupied areas, or corner case handling/work around/quirk occupied areas when doing system init. By the way, the top-down searching and loading of kexec-ed kernel is done in user space utility code. For kexec_file loading, even if kexec_buf.top_down is 'true', it's simply ignored. It calls walk_system_ram_res() directly to go through all resources of System RAM bottom up, to find an available memory region, then call locate_mem_hole_callback() to allocate memory in that found memory region from top to down. This is not expected and inconsistent with kexec_load. Implementation =============== In patch 1, introduce a new function walk_system_ram_res_rev() which is a variant of walk_system_ram_res(), it walks through a list of all the resources of System RAM in reversed order, i.e., from higher to lower. In patch 2, check if kexec_buf.top_down is 'true' in kexec_walk_resources(), if yes, call walk_system_ram_res_rev() to find memory region of system RAM from top to down to load kernel/initrd etc. Background information: ======================= And I ever tried this in the past in a different way, please see below link. In the post, I tried to adjust struct sibling linking code, replace the the singly linked list with list_head so that walk_system_ram_res_rev() can be implemented in a much easier way. Finally I failed. https://lore.kernel.org/all/20180718024944.577-4-bhe@redhat.com/ This time, I picked up the patch from AKASHI Takahiro's old post and made some change to take as the current patch 1: https://lists.infradead.org/pipermail/linux-arm-kernel/2017-September/531456.html This patch (of 2): Kexec_load interface has been doing top down searching and loading kernel/initrd/purgtory etc to prepare for kexec reboot. In that way, the benefits are that it avoids to consume and fragment limited low memory which satisfy DMA buffer allocation and big chunk of continuous memory during system init; and avoids to stir with BIOS/FW reserved or occupied areas, or corner case handling/work around/quirk occupied areas when doing system init. By the way, the top-down searching and loading of kexec-ed kernel is done in user space utility code. For kexec_file loading, even if kexec_buf.top_down is 'true', it's simply ignored. It calls walk_system_ram_res() directly to go through all resources of System RAM bottom up, to find an available memory region, then call locate_mem_hole_callback() to allocate memory in that found memory region from top to down. This is not expected and inconsistent with kexec_load. Here check if kexec_buf.top_down is 'true' in kexec_walk_resources(), if yes, call the newly added walk_system_ram_res_rev() to find memory region of system RAM from top to down to load kernel/initrd etc. Link: https://lkml.kernel.org/r/20231114091658.228030-1-bhe@redhat.com Link: https://lkml.kernel.org/r/20231114091658.228030-3-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Baoquan He <bhe@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-30Merge tag 'integrity-v6.6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull integrity subsystem updates from Mimi Zohar: - With commit 099f26f22f58 ("integrity: machine keyring CA configuration") certificates may be loaded onto the IMA keyring, directly or indirectly signed by keys on either the "builtin" or the "machine" keyrings. With the ability for the system/machine owner to sign the IMA policy itself without needing to recompile the kernel, update the IMA architecture specific policy rules to require the IMA policy itself be signed. [ As commit 099f26f22f58 was upstreamed in linux-6.4, updating the IMA architecture specific policy now to require signed IMA policies may break userspace expectations. ] - IMA only checked the file data hash was not on the system blacklist keyring for files with an appended signature (e.g. kernel modules, Power kernel image). Check all file data hashes regardless of how it was signed - Code cleanup, and a kernel-doc update * tag 'integrity-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: kexec_lock: Replace kexec_mutex() by kexec_lock() in two comments ima: require signed IMA policy when UEFI secure boot is enabled integrity: Always reference the blacklist keyring with appraisal ima: Remove deprecated IMA_TRUSTED_KEYRING Kconfig
2023-08-24kexec: exclude elfcorehdr from the segment digestEric DeVolder
When a crash kernel is loaded via the kexec_file_load() syscall, the kernel places the various segments (ie crash kernel, crash initrd, boot_params, elfcorehdr, purgatory, etc) in memory. For those architectures that utilize purgatory, a hash digest of the segments is calculated for integrity checking. The digest is embedded into the purgatory image prior to placing in memory. Updates to the elfcorehdr in response to CPU and memory changes would cause the purgatory integrity checking to fail (at crash time, and no vmcore created). Therefore, the elfcorehdr segment is explicitly excluded from the purgatory digest, enabling updates to the elfcorehdr while also avoiding the need to recompute the hash digest and reload purgatory. Link: https://lkml.kernel.org/r/20230814214446.6659-4-eric.devolder@oracle.com Signed-off-by: Eric DeVolder <eric.devolder@oracle.com> Suggested-by: Baoquan He <bhe@redhat.com> Reviewed-by: Sourabh Jain <sourabhjain@linux.ibm.com> Acked-by: Hari Bathini <hbathini@linux.ibm.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Akhil Raj <lf32.dev@gmail.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Sean Christopherson <seanjc@google.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Weißschuh <linux@weissschuh.net> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-24crash: move a few code bits to setup support of crash hotplugEric DeVolder
Patch series "crash: Kernel handling of CPU and memory hot un/plug", v28. Once the kdump service is loaded, if changes to CPUs or memory occur, either by hot un/plug or off/onlining, the crash elfcorehdr must also be updated. The elfcorehdr describes to kdump the CPUs and memory in the system, and any inaccuracies can result in a vmcore with missing CPU context or memory regions. The current solution utilizes udev to initiate an unload-then-reload of the kdump image (eg. kernel, initrd, boot_params, purgatory and elfcorehdr) by the userspace kexec utility. In the original post I outlined the significant performance problems related to offloading this activity to userspace. This patchset introduces a generic crash handler that registers with the CPU and memory notifiers. Upon CPU or memory changes, from either hot un/plug or off/onlining, this generic handler is invoked and performs important housekeeping, for example obtaining the appropriate lock, and then invokes an architecture specific handler to do the appropriate elfcorehdr update. Note the description in patch 'crash: change crash_prepare_elf64_headers() to for_each_possible_cpu()' and 'x86/crash: optimize CPU changes' that enables further optimizations related to CPU plug/unplug/online/offline performance of elfcorehdr updates. In the case of x86_64, the arch specific handler generates a new elfcorehdr, and overwrites the old one in memory; thus no involvement with userspace needed. To realize the benefits/test this patchset, one must make a couple of minor changes to userspace: - Prevent udev from updating kdump crash kernel on hot un/plug changes. Add the following as the first lines to the RHEL udev rule file /usr/lib/udev/rules.d/98-kexec.rules: # The kernel updates the crash elfcorehdr for CPU and memory changes SUBSYSTEM=="cpu", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end" SUBSYSTEM=="memory", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end" With this changeset applied, the two rules evaluate to false for CPU and memory change events and thus skip the userspace unload-then-reload of kdump. - Change to the kexec_file_load for loading the kdump kernel: Eg. on RHEL: in /usr/bin/kdumpctl, change to: standard_kexec_args="-p -d -s" which adds the -s to select kexec_file_load() syscall. This kernel patchset also supports kexec_load() with a modified kexec userspace utility. A working changeset to the kexec userspace utility is posted to the kexec-tools mailing list here: http://lists.infradead.org/pipermail/kexec/2023-May/027049.html To use the kexec-tools patch, apply, build and install kexec-tools, then change the kdumpctl's standard_kexec_args to replace the -s with --hotplug. The removal of -s reverts to the kexec_load syscall and the addition of --hotplug invokes the changes put forth in the kexec-tools patch. This patch (of 8): The crash hotplug support leans on the work for the kexec_file_load() syscall. To also support the kexec_load() syscall, a few bits of code need to be move outside of CONFIG_KEXEC_FILE. As such, these bits are moved out of kexec_file.c and into a common location crash_core.c. In addition, struct crash_mem and crash_notes were moved to new locales so that PROC_KCORE, which sets CRASH_CORE alone, builds correctly. No functionality change intended. Link: https://lkml.kernel.org/r/20230814214446.6659-1-eric.devolder@oracle.com Link: https://lkml.kernel.org/r/20230814214446.6659-2-eric.devolder@oracle.com Signed-off-by: Eric DeVolder <eric.devolder@oracle.com> Reviewed-by: Sourabh Jain <sourabhjain@linux.ibm.com> Acked-by: Hari Bathini <hbathini@linux.ibm.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Akhil Raj <lf32.dev@gmail.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Sean Christopherson <seanjc@google.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Weißschuh <linux@weissschuh.net> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18kexec: rename ARCH_HAS_KEXEC_PURGATORYEric DeVolder
The Kconfig refactor to consolidate KEXEC and CRASH options utilized option names of the form ARCH_SUPPORTS_<option>. Thus rename the ARCH_HAS_KEXEC_PURGATORY to ARCH_SUPPORTS_KEXEC_PURGATORY to follow the same. Link: https://lkml.kernel.org/r/20230712161545.87870-15-eric.devolder@oracle.com Signed-off-by: Eric DeVolder <eric.devolder@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-07kexec_lock: Replace kexec_mutex() by kexec_lock() in two commentsWenyu Liu
kexec_mutex is replaced by an atomic variable in 05c6257433b (panic, kexec: make __crash_kexec() NMI safe). But there are still two comments that referenced kexec_mutex, replace them by kexec_lock. Signed-off-by: Wenyu Liu <liuwenyu7@huawei.com> Acked-by: Baoquan He <bhe@redhat.com> Acked-by: Paul Menzel <pmenzel@molgen.mpg.de> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2023-06-28Merge tag 'mm-nonmm-stable-2023-06-24-19-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-mm updates from Andrew Morton: - Arnd Bergmann has fixed a bunch of -Wmissing-prototypes in top-level directories - Douglas Anderson has added a new "buddy" mode to the hardlockup detector. It permits the detector to work on architectures which cannot provide the required interrupts, by having CPUs periodically perform checks on other CPUs - Zhen Lei has enhanced kexec's ability to support two crash regions - Petr Mladek has done a lot of cleanup on the hard lockup detector's Kconfig entries - And the usual bunch of singleton patches in various places * tag 'mm-nonmm-stable-2023-06-24-19-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits) kernel/time/posix-stubs.c: remove duplicated include ocfs2: remove redundant assignment to variable bit_off watchdog/hardlockup: fix typo in config HARDLOCKUP_DETECTOR_PREFER_BUDDY powerpc: move arch_trigger_cpumask_backtrace from nmi.h to irq.h devres: show which resource was invalid in __devm_ioremap_resource() watchdog/hardlockup: define HARDLOCKUP_DETECTOR_ARCH watchdog/sparc64: define HARDLOCKUP_DETECTOR_SPARC64 watchdog/hardlockup: make HAVE_NMI_WATCHDOG sparc64-specific watchdog/hardlockup: declare arch_touch_nmi_watchdog() only in linux/nmi.h watchdog/hardlockup: make the config checks more straightforward watchdog/hardlockup: sort hardlockup detector related config values a logical way watchdog/hardlockup: move SMP barriers from common code to buddy code watchdog/buddy: simplify the dependency for HARDLOCKUP_DETECTOR_PREFER_BUDDY watchdog/buddy: don't copy the cpumask in watchdog_next_cpu() watchdog/buddy: cleanup how watchdog_buddy_check_hardlockup() is called watchdog/hardlockup: remove softlockup comment in touch_nmi_watchdog() watchdog/hardlockup: in watchdog_hardlockup_check() use cpumask_copy() watchdog/hardlockup: don't use raw_cpu_ptr() in watchdog_hardlockup_kick() watchdog/hardlockup: HAVE_NMI_WATCHDOG must implement watchdog_hardlockup_probe() watchdog/hardlockup: keep kernel.nmi_watchdog sysctl as 0444 if probe fails ...
2023-06-12kexec: support purgatories with .text.hot sectionsRicardo Ribalda
Patch series "kexec: Fix kexec_file_load for llvm16 with PGO", v7. When upreving llvm I realised that kexec stopped working on my test platform. The reason seems to be that due to PGO there are multiple .text sections on the purgatory, and kexec does not supports that. This patch (of 4): Clang16 links the purgatory text in two sections when PGO is in use: [ 1] .text PROGBITS 0000000000000000 00000040 00000000000011a1 0000000000000000 AX 0 0 16 [ 2] .rela.text RELA 0000000000000000 00003498 0000000000000648 0000000000000018 I 24 1 8 ... [17] .text.hot. PROGBITS 0000000000000000 00003220 000000000000020b 0000000000000000 AX 0 0 1 [18] .rela.text.hot. RELA 0000000000000000 00004428 0000000000000078 0000000000000018 I 24 17 8 And both of them have their range [sh_addr ... sh_addr+sh_size] on the area pointed by `e_entry`. This causes that image->start is calculated twice, once for .text and another time for .text.hot. The second calculation leaves image->start in a random location. Because of this, the system crashes immediately after: kexec_core: Starting new kernel Link: https://lkml.kernel.org/r/20230321-kexec_clang16-v7-0-b05c520b7296@chromium.org Link: https://lkml.kernel.org/r/20230321-kexec_clang16-v7-1-b05c520b7296@chromium.org Fixes: 930457057abe ("kernel/kexec_file.c: split up __kexec_load_puragory") Signed-off-by: Ricardo Ribalda <ribalda@chromium.org> Reviewed-by: Ross Zwisler <zwisler@google.com> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Reviewed-by: Philipp Rudo <prudo@redhat.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Palmer Dabbelt <palmer@rivosinc.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Simon Horman <horms@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Rix <trix@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09kexec: avoid calculating array size twiceSimon Horman
Avoid calculating array size twice in kexec_purgatory_setup_sechdrs(). Once using array_size(), and once open-coded. Flagged by Coccinelle: .../kexec_file.c:881:8-25: WARNING: array_size is already used (line 877) to compute the same size No functional change intended. Compile tested only. Link: https://lkml.kernel.org/r/20230525-kexec-array_size-v1-1-8b4bf4f7500a@kernel.org Signed-off-by: Simon Horman <horms@kernel.org> Acked-by: Baoquan He <bhe@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-08kexec: remove unnecessary arch_kexec_kernel_image_load()Bjorn Helgaas
arch_kexec_kernel_image_load() only calls kexec_image_load_default(), and there are no arch-specific implementations. Remove the unnecessary arch_kexec_kernel_image_load() and make kexec_image_load_default() static. No functional change intended. Link: https://lkml.kernel.org/r/20230307224416.907040-3-helgaas@kernel.org Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Acked-by: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02kexec: introduce sysctl parameters kexec_load_limit_*Ricardo Ribalda
kexec allows replacing the current kernel with a different one. This is usually a source of concerns for sysadmins that want to harden a system. Linux already provides a way to disable loading new kexec kernel via kexec_load_disabled, but that control is very coard, it is all or nothing and does not make distinction between a panic kexec and a normal kexec. This patch introduces new sysctl parameters, with finer tuning to specify how many times a kexec kernel can be loaded. The sysadmin can set different limits for kexec panic and kexec reboot kernels. The value can be modified at runtime via sysctl, but only with a stricter value. With these new parameters on place, a system with loadpin and verity enabled, using the following kernel parameters: sysctl.kexec_load_limit_reboot=0 sysct.kexec_load_limit_panic=1 can have a good warranty that if initrd tries to load a panic kernel, a malitious user will have small chances to replace that kernel with a different one, even if they can trigger timeouts on the disk where the panic kernel lives. Link: https://lkml.kernel.org/r/20221114-disable-kexec-reset-v6-3-6a8531a09b9a@chromium.org Signed-off-by: Ricardo Ribalda <ribalda@chromium.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Baoquan He <bhe@redhat.com> Cc: Bagas Sanjaya <bagasdotme@gmail.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Philipp Rudo <prudo@redhat.com> Cc: Ross Zwisler <zwisler@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02kexec: factor out kexec_load_permittedRicardo Ribalda
Both syscalls (kexec and kexec_file) do the same check, let's factor it out. Link: https://lkml.kernel.org/r/20221114-disable-kexec-reset-v6-2-6a8531a09b9a@chromium.org Signed-off-by: Ricardo Ribalda <ribalda@chromium.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Baoquan He <bhe@redhat.com> Cc: Bagas Sanjaya <bagasdotme@gmail.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Guilherme G. Piccoli <gpiccoli@igalia.com> Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Philipp Rudo <prudo@redhat.com> Cc: Ross Zwisler <zwisler@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-18kexec: replace crash_mem_range with rangeLi Chen
We already have struct range, so just use it. Link: https://lkml.kernel.org/r/20220929042936.22012-4-bhe@redhat.com Signed-off-by: Li Chen <lchen@ambarella.com> Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Chen Lifu <chenlifu@huawei.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: Jianglei Nie <niejianglei2021@163.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Russell King <linux@armlinux.org.uk> Cc: ye xingchen <ye.xingchen@zte.com.cn> Cc: Zeal Robot <zealci@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11panic, kexec: make __crash_kexec() NMI safeValentin Schneider
Attempting to get a crash dump out of a debug PREEMPT_RT kernel via an NMI panic() doesn't work. The cause of that lies in the PREEMPT_RT definition of mutex_trylock(): if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES) && WARN_ON_ONCE(!in_task())) return 0; This prevents an nmi_panic() from executing the main body of __crash_kexec() which does the actual kexec into the kdump kernel. The warning and return are explained by: 6ce47fd961fa ("rtmutex: Warn if trylock is called from hard/softirq context") [...] The reasons for this are: 1) There is a potential deadlock in the slowpath 2) Another cpu which blocks on the rtmutex will boost the task which allegedly locked the rtmutex, but that cannot work because the hard/softirq context borrows the task context. Furthermore, grabbing the lock isn't NMI safe, so do away with kexec_mutex and replace it with an atomic variable. This is somewhat overzealous as *some* callsites could keep using a mutex (e.g. the sysfs-facing ones like crash_shrink_memory()), but this has the benefit of involving a single unified lock and preventing any future NMI-related surprises. Tested by triggering NMI panics via: $ echo 1 > /proc/sys/kernel/panic_on_unrecovered_nmi $ echo 1 > /proc/sys/kernel/unknown_nmi_panic $ echo 1 > /proc/sys/kernel/panic $ ipmitool power diag Link: https://lkml.kernel.org/r/20220630223258.4144112-3-vschneid@redhat.com Fixes: 6ce47fd961fa ("rtmutex: Warn if trylock is called from hard/softirq context") Signed-off-by: Valentin Schneider <vschneid@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baoquan He <bhe@redhat.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: Juri Lelli <jlelli@redhat.com> Cc: Luis Claudio R. Goncalves <lgoncalv@redhat.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-07Merge tag 'mm-nonmm-stable-2022-08-06-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc updates from Andrew Morton: "Updates to various subsystems which I help look after. lib, ocfs2, fatfs, autofs, squashfs, procfs, etc. A relatively small amount of material this time" * tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits) scripts/gdb: ensure the absolute path is generated on initial source MAINTAINERS: kunit: add David Gow as a maintainer of KUnit mailmap: add linux.dev alias for Brendan Higgins mailmap: update Kirill's email profile: setup_profiling_timer() is moslty not implemented ocfs2: fix a typo in a comment ocfs2: use the bitmap API to simplify code ocfs2: remove some useless functions lib/mpi: fix typo 'the the' in comment proc: add some (hopefully) insightful comments bdi: remove enum wb_congested_state kernel/hung_task: fix address space of proc_dohung_task_timeout_secs lib/lzo/lzo1x_compress.c: replace ternary operator with min() and min_t() squashfs: support reading fragments in readahead call squashfs: implement readahead squashfs: always build "file direct" version of page actor Revert "squashfs: provide backing_dev_info in order to disable read-ahead" fs/ocfs2: Fix spelling typo in comment ia64: old_rr4 added under CONFIG_HUGETLB_PAGE proc: fix test for "vsyscall=xonly" boot option ...
2022-07-15kexec, KEYS: make the code in bzImage64_verify_sig genericCoiby Xu
commit 278311e417be ("kexec, KEYS: Make use of platform keyring for signature verify") adds platform keyring support on x86 kexec but not arm64. The code in bzImage64_verify_sig uses the keys on the .builtin_trusted_keys, .machine, if configured and enabled, .secondary_trusted_keys, also if configured, and .platform keyrings to verify the signed kernel image as PE file. Cc: kexec@lists.infradead.org Cc: keyrings@vger.kernel.org Cc: linux-security-module@vger.kernel.org Reviewed-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Coiby Xu <coxu@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-07-15kexec: clean up arch_kexec_kernel_verify_sigCoiby Xu
Before commit 105e10e2cf1c ("kexec_file: drop weak attribute from functions"), there was already no arch-specific implementation of arch_kexec_kernel_verify_sig. With weak attribute dropped by that commit, arch_kexec_kernel_verify_sig is completely useless. So clean it up. Note later patches are dependent on this patch so it should be backported to the stable tree as well. Cc: stable@vger.kernel.org Suggested-by: Eric W. Biederman <ebiederm@xmission.com> Reviewed-by: Michal Suchanek <msuchanek@suse.de> Acked-by: Baoquan He <bhe@redhat.com> Signed-off-by: Coiby Xu <coxu@redhat.com> [zohar@linux.ibm.com: reworded patch description "Note"] Link: https://lore.kernel.org/linux-integrity/20220714134027.394370-1-coxu@redhat.com/ Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-07-15kexec_file: drop weak attribute from functionsNaveen N. Rao
As requested (http://lkml.kernel.org/r/87ee0q7b92.fsf@email.froward.int.ebiederm.org), this series converts weak functions in kexec to use the #ifdef approach. Quoting the 3e35142ef99fe ("kexec_file: drop weak attribute from arch_kexec_apply_relocations[_add]") changelog: : Since commit d1bcae833b32f1 ("ELF: Don't generate unused section symbols") : [1], binutils (v2.36+) started dropping section symbols that it thought : were unused. This isn't an issue in general, but with kexec_file.c, gcc : is placing kexec_arch_apply_relocations[_add] into a separate : .text.unlikely section and the section symbol ".text.unlikely" is being : dropped. Due to this, recordmcount is unable to find a non-weak symbol in : .text.unlikely to generate a relocation record against. This patch (of 2); Drop __weak attribute from functions in kexec_file.c: - arch_kexec_kernel_image_probe() - arch_kimage_file_post_load_cleanup() - arch_kexec_kernel_image_load() - arch_kexec_locate_mem_hole() - arch_kexec_kernel_verify_sig() arch_kexec_kernel_image_load() calls into kexec_image_load_default(), so drop the static attribute for the latter. arch_kexec_kernel_verify_sig() is not overridden by any architecture, so drop the __weak attribute. Link: https://lkml.kernel.org/r/cover.1656659357.git.naveen.n.rao@linux.vnet.ibm.com Link: https://lkml.kernel.org/r/2cd7ca1fe4d6bb6ca38e3283c717878388ed6788.1656659357.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Suggested-by: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-07-13ima: force signature verification when CONFIG_KEXEC_SIG is configuredCoiby Xu
Currently, an unsigned kernel could be kexec'ed when IMA arch specific policy is configured unless lockdown is enabled. Enforce kernel signature verification check in the kexec_file_load syscall when IMA arch specific policy is configured. Fixes: 99d5cadfde2b ("kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE") Reported-and-suggested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Coiby Xu <coxu@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-06-16kexec_file: increase maximum file size to 4GPasha Tatashin
In some case initrd can be large. For example, it could be a netboot image loaded by u-root, that is kexec'ing into it. The maximum size of initrd is arbitrary set to 2G. Also, the limit is not very obvious because it is hidden behind a generic INT_MAX macro. Theoretically, we could make it LONG_MAX, but it is safer to keep it sane, and just increase it to 4G. Increase the size to 4G, and make it obvious by having a new macro that specifies the maximum file size supported by kexec_file_load() syscall: KEXEC_FILE_SIZE_MAX. Link: https://lkml.kernel.org/r/20220527025535.3953665-3-pasha.tatashin@soleen.com Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Sasha Levin <sashal@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Greg Thelen <gthelen@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-31Merge tag 'riscv-for-linus-5.19-mw0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for the Svpbmt extension, which allows memory attributes to be encoded in pages - Support for the Allwinner D1's implementation of page-based memory attributes - Support for running rv32 binaries on rv64 systems, via the compat subsystem - Support for kexec_file() - Support for the new generic ticket-based spinlocks, which allows us to also move to qrwlock. These should have already gone in through the asm-geneic tree as well - A handful of cleanups and fixes, include some larger ones around atomics and XIP * tag 'riscv-for-linus-5.19-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits) RISC-V: Prepare dropping week attribute from arch_kexec_apply_relocations[_add] riscv: compat: Using seperated vdso_maps for compat_vdso_info RISC-V: Fix the XIP build RISC-V: Split out the XIP fixups into their own file RISC-V: ignore xipImage RISC-V: Avoid empty create_*_mapping definitions riscv: Don't output a bogus mmu-type on a no MMU kernel riscv: atomic: Add custom conditional atomic operation implementation riscv: atomic: Optimize dec_if_positive functions riscv: atomic: Cleanup unnecessary definition RISC-V: Load purgatory in kexec_file RISC-V: Add purgatory RISC-V: Support for kexec_file on panic RISC-V: Add kexec_file support RISC-V: use memcpy for kexec_file mode kexec_file: Fix kexec_file.c build error for riscv platform riscv: compat: Add COMPAT Kbuild skeletal support riscv: compat: ptrace: Add compat_arch_ptrace implement riscv: compat: signal: Add rt_frame implementation riscv: add memory-type errata for T-Head ...
2022-05-27kexec_file: drop weak attribute from arch_kexec_apply_relocations[_add]Naveen N. Rao
Since commit d1bcae833b32f1 ("ELF: Don't generate unused section symbols") [1], binutils (v2.36+) started dropping section symbols that it thought were unused. This isn't an issue in general, but with kexec_file.c, gcc is placing kexec_arch_apply_relocations[_add] into a separate .text.unlikely section and the section symbol ".text.unlikely" is being dropped. Due to this, recordmcount is unable to find a non-weak symbol in .text.unlikely to generate a relocation record against. Address this by dropping the weak attribute from these functions. Instead, follow the existing pattern of having architectures #define the name of the function they want to override in their headers. [1] https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=d1bcae833b32f1 [akpm@linux-foundation.org: arch/s390/include/asm/kexec.h needs linux/module.h] Link: https://lkml.kernel.org/r/20220519091237.676736-1-naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-19kexec_file: Fix kexec_file.c build error for riscv platformLiao Chang
When CONFIG_KEXEC_FILE is set for riscv platform, the compilation of kernel/kexec_file.c generate build error: kernel/kexec_file.c: In function 'crash_prepare_elf64_headers': ./arch/riscv/include/asm/page.h:110:71: error: request for member 'virt_addr' in something not a structure or union 110 | ((x) >= PAGE_OFFSET && (!IS_ENABLED(CONFIG_64BIT) || (x) < kernel_map.virt_addr)) | ^ ./arch/riscv/include/asm/page.h:131:2: note: in expansion of macro 'is_linear_mapping' 131 | is_linear_mapping(_x) ? \ | ^~~~~~~~~~~~~~~~~ ./arch/riscv/include/asm/page.h:140:31: note: in expansion of macro '__va_to_pa_nodebug' 140 | #define __phys_addr_symbol(x) __va_to_pa_nodebug(x) | ^~~~~~~~~~~~~~~~~~ ./arch/riscv/include/asm/page.h:143:24: note: in expansion of macro '__phys_addr_symbol' 143 | #define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0)) | ^~~~~~~~~~~~~~~~~~ kernel/kexec_file.c:1327:36: note: in expansion of macro '__pa_symbol' 1327 | phdr->p_offset = phdr->p_paddr = __pa_symbol(_text); This occurs is because the "kernel_map" referenced in macro is_linear_mapping() is suppose to be the one of struct kernel_mapping defined in arch/riscv/mm/init.c, but the 2nd argument of crash_prepare_elf64_header() has same symbol name, in expansion of macro is_linear_mapping in function crash_prepare_elf64_header(), "kernel_map" actually is the local variable. Signed-off-by: Liao Chang <liaochang1@huawei.com> Link: https://lore.kernel.org/r/20220408100914.150110-2-lizhengyu3@huawei.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2021-11-06memblock: add MEMBLOCK_DRIVER_MANAGED to mimic IORESOURCE_SYSRAM_DRIVER_MANAGEDDavid Hildenbrand
Let's add a flag that corresponds to IORESOURCE_SYSRAM_DRIVER_MANAGED, indicating that we're dealing with a memory region that is never indicated in the firmware-provided memory map, but always detected and added by a driver. Similar to MEMBLOCK_HOTPLUG, most infrastructure has to treat such memory regions like ordinary MEMBLOCK_NONE memory regions -- for example, when selecting memory regions to add to the vmcore for dumping in the crashkernel via for_each_mem_range(). However, especially kexec_file is not supposed to select such memblocks via for_each_free_mem_range() / for_each_free_mem_range_reverse() to place kexec images, similar to how we handle IORESOURCE_SYSRAM_DRIVER_MANAGED without CONFIG_ARCH_KEEP_MEMBLOCK. We'll make sure that memory hotplug code sets the flag where applicable (IORESOURCE_SYSRAM_DRIVER_MANAGED) next. This prepares architectures that need CONFIG_ARCH_KEEP_MEMBLOCK, such as arm64, for virtio-mem support. Note that kexec *must not* indicate this memory to the second kernel and *must not* place kexec-images on this memory. Let's add a comment to kexec_walk_memblock(), documenting how we handle MEMBLOCK_DRIVER_MANAGED now just like using IORESOURCE_SYSRAM_DRIVER_MANAGED in locate_mem_hole_callback() for kexec_walk_resources(). Also note that MEMBLOCK_HOTPLUG cannot be reused due to different semantics: MEMBLOCK_HOTPLUG: memory is indicated as "System RAM" in the firmware-provided memory map and added to the system early during boot; kexec *has to* indicate this memory to the second kernel and can place kexec-images on this memory. After memory hotunplug, kexec has to be re-armed. We mostly ignore this flag when "movable_node" is not set on the kernel command line, because then we're told to not care about hotunpluggability of such memory regions. MEMBLOCK_DRIVER_MANAGED: memory is not indicated as "System RAM" in the firmware-provided memory map; this memory is always detected and added to the system by a driver; memory might not actually be physically hotunpluggable. kexec *must not* indicate this memory to the second kernel and *must not* place kexec-images on this memory. Link: https://lkml.kernel.org/r/20211004093605.5830-5-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Jianyong Wu <Jianyong.Wu@arm.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Shahab Vahedi <shahab@synopsys.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel: kexec_file: fix error return code of kexec_calculate_store_digests()Jia-Ju Bai
When vzalloc() returns NULL to sha_regions, no error return code of kexec_calculate_store_digests() is assigned. To fix this bug, ret is assigned with -ENOMEM in this case. Link: https://lkml.kernel.org/r/20210309083904.24321-1-baijiaju1990@gmail.com Fixes: a43cac0d9dc2 ("kexec: split kexec_file syscall code to kexec_file.c") Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Reported-by: TOTE Robot <oslab@tsinghua.edu.cn> Acked-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-10ima: Free IMA measurement buffer after kexec syscallLakshmi Ramasubramanian
IMA allocates kernel virtual memory to carry forward the measurement list, from the current kernel to the next kernel on kexec system call, in ima_add_kexec_buffer() function. This buffer is not freed before completing the kexec system call resulting in memory leak. Add ima_buffer field in "struct kimage" to store the virtual address of the buffer allocated for the IMA measurement list. Free the memory allocated for the IMA measurement list in kimage_file_post_load_cleanup() function. Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Suggested-by: Tyler Hicks <tyhicks@linux.microsoft.com> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com> Fixes: 7b8589cc29e7 ("ima: on soft reboot, save the measurement list") Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-11-20crypto: sha - split sha.h into sha1.h and sha2.hEric Biggers
Currently <crypto/sha.h> contains declarations for both SHA-1 and SHA-2, and <crypto/sha3.h> contains declarations for SHA-3. This organization is inconsistent, but more importantly SHA-1 is no longer considered to be cryptographically secure. So to the extent possible, SHA-1 shouldn't be grouped together with any of the other SHA versions, and usage of it should be phased out. Therefore, split <crypto/sha.h> into two headers <crypto/sha1.h> and <crypto/sha2.h>, and make everyone explicitly specify whether they want the declarations for SHA-1, SHA-2, or both. This avoids making the SHA-1 declarations visible to files that don't want anything to do with SHA-1. It also prepares for potentially moving sha1.h into a new insecure/ or dangerous/ directory. Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-10-16kernel/resource: move and rename IORESOURCE_MEM_DRIVER_MANAGEDDavid Hildenbrand
IORESOURCE_MEM_DRIVER_MANAGED currently uses an unused PnP bit, which is always set to 0 by hardware. This is far from beautiful (and confusing), and the bit only applies to SYSRAM. So let's move it out of the bus-specific (PnP) defined bits. We'll add another SYSRAM specific bit soon. If we ever need more bits for other purposes, we can steal some from "desc", or reshuffle/regroup what we have. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kees Cook <keescook@chromium.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Baoquan He <bhe@redhat.com> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Julien Grall <julien@xen.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Len Brown <lenb@kernel.org> Cc: Leonardo Bras <leobras.c@gmail.com> Cc: Libor Pechacek <lpechacek@suse.cz> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Roger Pau Monné <roger.pau@citrix.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Wei Liu <wei.liu@kernel.org> Link: https://lkml.kernel.org/r/20200911103459.10306-3-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-05fs/kernel_file_read: Add "offset" arg for partial readsKees Cook
To perform partial reads, callers of kernel_read_file*() must have a non-NULL file_size argument and a preallocated buffer. The new "offset" argument can then be used to seek to specific locations in the file to fill the buffer to, at most, "buf_size" per call. Where possible, the LSM hooks can report whether a full file has been read or not so that the contents can be reasoned about. Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20201002173828.2099543-14-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05fs/kernel_read_file: Add file_size output argumentKees Cook
In preparation for adding partial read support, add an optional output argument to kernel_read_file*() that reports the file size so callers can reason more easily about their reading progress. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Scott Branden <scott.branden@broadcom.com> Link: https://lore.kernel.org/r/20201002173828.2099543-8-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05fs/kernel_read_file: Remove redundant size argumentKees Cook
In preparation for refactoring kernel_read_file*(), remove the redundant "size" argument which is not needed: it can be included in the return code, with callers adjusted. (VFS reads already cannot be larger than INT_MAX.) Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Scott Branden <scott.branden@broadcom.com> Link: https://lore.kernel.org/r/20201002173828.2099543-6-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05fs/kernel_read_file: Split into separate include fileScott Branden
Move kernel_read_file* out of linux/fs.h to its own linux/kernel_read_file.h include file. That header gets pulled in just about everywhere and doesn't really need functions not related to the general fs interface. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Scott Branden <scott.branden@broadcom.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: James Morris <jamorris@linux.microsoft.com> Link: https://lore.kernel.org/r/20200706232309.12010-2-scott.branden@broadcom.com Link: https://lore.kernel.org/r/20201002173828.2099543-4-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-15Merge tag 'x86-urgent-2020-08-15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes and small updates all around the place: - Fix mitigation state sysfs output - Fix an FPU xstate/sxave code assumption bug triggered by Architectural LBR support - Fix Lightning Mountain SoC TSC frequency enumeration bug - Fix kexec debug output - Fix kexec memory range assumption bug - Fix a boundary condition in the crash kernel code - Optimize porgatory.ro generation a bit - Enable ACRN guests to use X2APIC mode - Reduce a __text_poke() IRQs-off critical section for the benefit of PREEMPT_RT" * tag 'x86-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/alternatives: Acquire pte lock with interrupts enabled x86/bugs/multihit: Fix mitigation reporting when VMX is not in use x86/fpu/xstate: Fix an xstate size check warning with architectural LBRs x86/purgatory: Don't generate debug info for purgatory.ro x86/tsr: Fix tsc frequency enumeration bug on Lightning Mountain SoC kexec_file: Correctly output debugging information for the PT_LOAD ELF header kexec: Improve & fix crash_exclude_mem_range() to handle overlapping ranges x86/crash: Correct the address boundary of function parameters x86/acrn: Remove redundant chars from ACRN signature x86/acrn: Allow ACRN guest to use X2APIC mode
2020-08-07Merge tag 'powerpc-5.9-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Add support for (optionally) using queued spinlocks & rwlocks. - Support for a new faster system call ABI using the scv instruction on Power9 or later. - Drop support for the PROT_SAO mmap/mprotect flag as it will be unsupported on Power10 and future processors, leaving us with no way to implement the functionality it requests. This risks breaking userspace, though we believe it is unused in practice. - A bug fix for, and then the removal of, our custom stack expansion checking. We now allow stack expansion up to the rlimit, like other architectures. - Remove the remnants of our (previously disabled) topology update code, which tried to react to NUMA layout changes on virtualised systems, but was prone to crashes and other problems. - Add PMU support for Power10 CPUs. - A change to our signal trampoline so that we don't unbalance the link stack (branch return predictor) in the signal delivery path. - Lots of other cleanups, refactorings, smaller features and so on as usual. Thanks to: Abhishek Goel, Alastair D'Silva, Alexander A. Klimov, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Balamuruhan S, Bharata B Rao, Bill Wendling, Bin Meng, Cédric Le Goater, Chris Packham, Christophe Leroy, Christoph Hellwig, Daniel Axtens, Dan Williams, David Lamparter, Desnes A. Nunes do Rosario, Erhard F., Finn Thain, Frederic Barrat, Ganesh Goudar, Gautham R. Shenoy, Geoff Levand, Greg Kurz, Gustavo A. R. Silva, Hari Bathini, Harish, Imre Kaloz, Joel Stanley, Joe Perches, John Crispin, Jordan Niethe, Kajol Jain, Kamalesh Babulal, Kees Cook, Laurent Dufour, Leonardo Bras, Li RongQing, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Cave-Ayland, Michal Suchanek, Milton Miller, Mimi Zohar, Murilo Opsfelder Araujo, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nayna Jain, Nicholas Piggin, Oliver O'Halloran, Palmer Dabbelt, Pedro Miraglia Franco de Carvalho, Philippe Bergheaud, Pingfan Liu, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Randy Dunlap, Ravi Bangoria, Sachin Sant, Sam Bobroff, Sandipan Das, Santosh Sivaraj, Satheesh Rajendran, Shirisha Ganta, Sourabh Jain, Srikar Dronamraju, Stan Johnson, Stephen Rothwell, Thadeu Lima de Souza Cascardo, Thiago Jung Bauermann, Tom Lane, Vaibhav Jain, Vladis Dronov, Wei Yongjun, Wen Xiong, YueHaibing. * tag 'powerpc-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (337 commits) selftests/powerpc: Fix pkey syscall redefinitions powerpc: Fix circular dependency between percpu.h and mmu.h powerpc/powernv/sriov: Fix use of uninitialised variable selftests/powerpc: Skip vmx/vsx/tar/etc tests on older CPUs powerpc/40x: Fix assembler warning about r0 powerpc/papr_scm: Add support for fetching nvdimm 'fuel-gauge' metric powerpc/papr_scm: Fetch nvdimm performance stats from PHYP cpuidle: pseries: Fixup exit latency for CEDE(0) cpuidle: pseries: Add function to parse extended CEDE records cpuidle: pseries: Set the latency-hint before entering CEDE selftests/powerpc: Fix online CPU selection powerpc/perf: Consolidate perf_callchain_user_[64|32]() powerpc/pseries/hotplug-cpu: Remove double free in error path powerpc/pseries/mobility: Add pr_debug() for device tree changes powerpc/pseries/mobility: Set pr_fmt() powerpc/cacheinfo: Warn if cache object chain becomes unordered powerpc/cacheinfo: Improve diagnostics about malformed cache lists powerpc/cacheinfo: Use name@unit instead of full DT path in debug messages powerpc/cacheinfo: Set pr_fmt() powerpc: fix function annotations to avoid section mismatch warnings with gcc-10 ...
2020-08-07kexec_file: Correctly output debugging information for the PT_LOAD ELF headerLianbo Jiang
Currently, when we enable the debugging switch to debug kexec_file, we always get the following incorrect results: kexec_file: Crash PT_LOAD elf header. phdr=00000000c988639b vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=51 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000003cca69a0 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=52 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000c584cb9f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=53 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000cf85d57f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=54 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000a4a8f847 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=55 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000272ec49f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=56 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000ea0b65de vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=57 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000001f5e490c vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=58 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000dfe4109e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=59 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000480ed2b6 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=60 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000080b65151 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=61 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000024e31c5e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=62 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000332e0385 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=63 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000002754d5da vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=64 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000783320dd vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=65 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000076fe5b64 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=66 p_offset=0x0 The reason is that kernel always prints the values of the next PT_LOAD instead of the current PT_LOAD. Change it to ensure that we can get the correct debugging information. [ mingo: Amended changelog, capitalized "ELF". ] Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Young <dyoung@redhat.com> Link: https://lore.kernel.org/r/20200804044933.1973-4-lijiang@redhat.com