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2025-04-07mm/page_alloc: fix memory accept before watermarks gets initializedKirill A. Shutemov1-2/+12
commit 800f1059c99e2b39899bdc67a7593a7bea6375d8 upstream. Watermarks are initialized during the postcore initcall. Until then, all watermarks are set to zero. This causes cond_accept_memory() to incorrectly skip memory acceptance because a watermark of 0 is always met. This can lead to a premature OOM on boot. To ensure progress, accept one MAX_ORDER page if the watermark is zero. Link: https://lkml.kernel.org/r/20250310082855.2587122-1-kirill.shutemov@linux.intel.com Fixes: dcdfdd40fa82 ("mm: Add support for unaccepted memory") Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Farrah Chen <farrah.chen@intel.com> Reported-by: Farrah Chen <farrah.chen@intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Cc: Ashish Kalra <ashish.kalra@amd.com> Cc: David Hildenbrand <david@redhat.com> Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: "Mike Rapoport (IBM)" <rppt@kernel.org> Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: <stable@vger.kernel.org> [6.5+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-28mm/migrate: fix shmem xarray update during migrationZi Yan1-6/+4
commit 60cf233b585cdf1f3c5e52d1225606b86acd08b0 upstream. A shmem folio can be either in page cache or in swap cache, but not at the same time. Namely, once it is in swap cache, folio->mapping should be NULL, and the folio is no longer in a shmem mapping. In __folio_migrate_mapping(), to determine the number of xarray entries to update, folio_test_swapbacked() is used, but that conflates shmem in page cache case and shmem in swap cache case. It leads to xarray multi-index entry corruption, since it turns a sibling entry to a normal entry during xas_store() (see [1] for a userspace reproduction). Fix it by only using folio_test_swapcache() to determine whether xarray is storing swap cache entries or not to choose the right number of xarray entries to update. [1] https://lore.kernel.org/linux-mm/Z8idPCkaJW1IChjT@casper.infradead.org/ Note: In __split_huge_page(), folio_test_anon() && folio_test_swapcache() is used to get swap_cache address space, but that ignores the shmem folio in swap cache case. It could lead to NULL pointer dereferencing when a in-swap-cache shmem folio is split at __xa_store(), since !folio_test_anon() is true and folio->mapping is NULL. But fortunately, its caller split_huge_page_to_list_to_order() bails out early with EBUSY when folio->mapping is NULL. So no need to take care of it here. Link: https://lkml.kernel.org/r/20250305200403.2822855-1-ziy@nvidia.com Fixes: fc346d0a70a1 ("mm: migrate high-order folios in swap cache correctly") Signed-off-by: Zi Yan <ziy@nvidia.com> Reported-by: Liu Shixin <liushixin2@huawei.com> Closes: https://lore.kernel.org/all/28546fb4-5210-bf75-16d6-43e1f8646080@huawei.com/ Suggested-by: Hugh Dickins <hughd@google.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Charan Teja Kalla <quic_charante@quicinc.com> Cc: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Lance Yang <ioworker0@gmail.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-28mm: fix error handling in __filemap_get_folio() with FGP_NOWAITRaphael S. Carvalho1-1/+12
commit 182db972c9568dc530b2f586a2f82dfd039d9f2a upstream. original report: https://lore.kernel.org/all/CAKhLTr1UL3ePTpYjXOx2AJfNk8Ku2EdcEfu+CH1sf3Asr=B-Dw@mail.gmail.com/T/ When doing buffered writes with FGP_NOWAIT, under memory pressure, the system returned ENOMEM despite there being plenty of available memory, to be reclaimed from page cache. The user space used io_uring interface, which in turn submits I/O with FGP_NOWAIT (the fast path). retsnoop pointed to iomap_get_folio: 00:34:16.180612 -> 00:34:16.180651 TID/PID 253786/253721 (reactor-1/combined_tests): entry_SYSCALL_64_after_hwframe+0x76 do_syscall_64+0x82 __do_sys_io_uring_enter+0x265 io_submit_sqes+0x209 io_issue_sqe+0x5b io_write+0xdd xfs_file_buffered_write+0x84 iomap_file_buffered_write+0x1a6 32us [-ENOMEM] iomap_write_begin+0x408 iter=&{.inode=0xffff8c67aa031138,.len=4096,.flags=33,.iomap={.addr=0xffffffffffffffff,.length=4096,.type=1,.flags=3,.bdev=0x… pos=0 len=4096 foliop=0xffffb32c296b7b80 ! 4us [-ENOMEM] iomap_get_folio iter=&{.inode=0xffff8c67aa031138,.len=4096,.flags=33,.iomap={.addr=0xffffffffffffffff,.length=4096,.type=1,.flags=3,.bdev=0x… pos=0 len=4096 This is likely a regression caused by 66dabbb65d67 ("mm: return an ERR_PTR from __filemap_get_folio"), which moved error handling from io_map_get_folio() to __filemap_get_folio(), but broke FGP_NOWAIT handling, so ENOMEM is being escaped to user space. Had it correctly returned -EAGAIN with NOWAIT, either io_uring or user space itself would be able to retry the request. It's not enough to patch io_uring since the iomap interface is the one responsible for it, and pwritev2(RWF_NOWAIT) and AIO interfaces must return the proper error too. The patch was tested with scylladb test suite (its original reproducer), and the tests all pass now when memory is pressured. Link: https://lkml.kernel.org/r/20250224143700.23035-1-raphaelsc@scylladb.com Fixes: 66dabbb65d67 ("mm: return an ERR_PTR from __filemap_get_folio") Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Matthew Wilcow (Oracle) <willy@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-22mm: split critical region in remap_file_pages() and invoke LSMs in betweenKirill A. Shutemov1-17/+52
commit 58a039e679fe72bd0efa8b2abe669a7914bb4429 upstream. Commit ea7e2d5e49c0 ("mm: call the security_mmap_file() LSM hook in remap_file_pages()") fixed a security issue, it added an LSM check when trying to remap file pages, so that LSMs have the opportunity to evaluate such action like for other memory operations such as mmap() and mprotect(). However, that commit called security_mmap_file() inside the mmap_lock lock, while the other calls do it before taking the lock, after commit 8b3ec6814c83 ("take security_mmap_file() outside of ->mmap_sem"). This caused lock inversion issue with IMA which was taking the mmap_lock and i_mutex lock in the opposite way when the remap_file_pages() system call was called. Solve the issue by splitting the critical region in remap_file_pages() in two regions: the first takes a read lock of mmap_lock, retrieves the VMA and the file descriptor associated, and calculates the 'prot' and 'flags' variables; the second takes a write lock on mmap_lock, checks that the VMA flags and the VMA file descriptor are the same as the ones obtained in the first critical region (otherwise the system call fails), and calls do_mmap(). In between, after releasing the read lock and before taking the write lock, call security_mmap_file(), and solve the lock inversion issue. Link: https://lkml.kernel.org/r/20241018161415.3845146-1-roberto.sassu@huaweicloud.com Fixes: ea7e2d5e49c0 ("mm: call the security_mmap_file() LSM hook in remap_file_pages()") Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reported-by: syzbot+1cd571a672400ef3a930@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-security-module/66f7b10e.050a0220.46d20.0036.GAE@google.com/ Tested-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Jann Horn <jannh@google.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Reviewed-by: Paul Moore <paul@paul-moore.com> Tested-by: syzbot+1cd571a672400ef3a930@syzkaller.appspotmail.com Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> Cc: Eric Snowberg <eric.snowberg@oracle.com> Cc: James Morris <jmorris@namei.org> Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Shu Han <ebpqwerty472123@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jianqi Ren <jianqi.ren.cn@windriver.com> Signed-off-by: He Zhe <zhe.he@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-22mm: add nommu variant of vm_insert_pages()Jens Axboe1-0/+7
Commit 62346c6cb28b043f2a6e95337d9081ec0b37b5f5 upstream. An identical one exists for vm_insert_page(), add one for vm_insert_pages() to avoid needing to check for CONFIG_MMU in code using it. Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-13mm: hugetlb: Add huge page size param to huge_ptep_get_and_clear()Ryan Roberts1-2/+2
commit 02410ac72ac3707936c07ede66e94360d0d65319 upstream. In order to fix a bug, arm64 needs to be told the size of the huge page for which the huge_pte is being cleared in huge_ptep_get_and_clear(). Provide for this by adding an `unsigned long sz` parameter to the function. This follows the same pattern as huge_pte_clear() and set_huge_pte_at(). This commit makes the required interface modifications to the core mm as well as all arches that implement this function (arm64, loongarch, mips, parisc, powerpc, riscv, s390, sparc). The actual arm64 bug will be fixed in a separate commit. Cc: stable@vger.kernel.org Fixes: 66b3923a1a0f ("arm64: hugetlb: add support for PTE contiguous bit") Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> # riscv Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> 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> Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> # s390 Link: https://lore.kernel.org/r/20250226120656.2400136-2-ryan.roberts@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-13mm: don't skip arch_sync_kernel_mappings() in error pathsRyan Roberts2-4/+6
commit 3685024edd270f7c791f993157d65d3c928f3d6e upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-13mm/page_alloc: fix uninitialized variableHao Zhang1-0/+1
commit 8fe9ed44dc29fba0786b7e956d2e87179e407582 upstream. The variable "compact_result" is not initialized in function __alloc_pages_slowpath(). It causes should_compact_retry() to use an uninitialized value. Initialize variable "compact_result" with the value COMPACT_SKIPPED. BUG: KMSAN: uninit-value in __alloc_pages_slowpath+0xee8/0x16c0 mm/page_alloc.c:4416 __alloc_pages_slowpath+0xee8/0x16c0 mm/page_alloc.c:4416 __alloc_frozen_pages_noprof+0xa4c/0xe00 mm/page_alloc.c:4752 alloc_pages_mpol+0x4cd/0x890 mm/mempolicy.c:2270 alloc_frozen_pages_noprof mm/mempolicy.c:2341 [inline] alloc_pages_noprof mm/mempolicy.c:2361 [inline] folio_alloc_noprof+0x1dc/0x350 mm/mempolicy.c:2371 filemap_alloc_folio_noprof+0xa6/0x440 mm/filemap.c:1019 __filemap_get_folio+0xb9a/0x1840 mm/filemap.c:1970 grow_dev_folio fs/buffer.c:1039 [inline] grow_buffers fs/buffer.c:1105 [inline] __getblk_slow fs/buffer.c:1131 [inline] bdev_getblk+0x2c9/0xab0 fs/buffer.c:1431 getblk_unmovable include/linux/buffer_head.h:369 [inline] ext4_getblk+0x3b7/0xe50 fs/ext4/inode.c:864 ext4_bread_batch+0x9f/0x7d0 fs/ext4/inode.c:933 __ext4_find_entry+0x1ebb/0x36c0 fs/ext4/namei.c:1627 ext4_lookup_entry fs/ext4/namei.c:1729 [inline] ext4_lookup+0x189/0xb40 fs/ext4/namei.c:1797 __lookup_slow+0x538/0x710 fs/namei.c:1793 lookup_slow+0x6a/0xd0 fs/namei.c:1810 walk_component fs/namei.c:2114 [inline] link_path_walk+0xf29/0x1420 fs/namei.c:2479 path_openat+0x30f/0x6250 fs/namei.c:3985 do_filp_open+0x268/0x600 fs/namei.c:4016 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x2a1/0x310 fs/open.c:1454 x64_sys_call+0x36f5/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:258 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Local variable compact_result created at: __alloc_pages_slowpath+0x66/0x16c0 mm/page_alloc.c:4218 __alloc_frozen_pages_noprof+0xa4c/0xe00 mm/page_alloc.c:4752 Link: https://lkml.kernel.org/r/tencent_ED1032321D6510B145CDBA8CBA0093178E09@qq.com Reported-by: syzbot+0cfd5e38e96a5596f2b6@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=0cfd5e38e96a5596f2b6 Signed-off-by: Hao Zhang <zhanghao1@kylinos.cn> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-13NFS: fix nfs_release_folio() to not deadlock via kcompactd writebackMike Snitzer1-0/+3
commit ce6d9c1c2b5cc785016faa11b48b6cd317eb367e upstream. Add PF_KCOMPACTD flag and current_is_kcompactd() helper to check for it so nfs_release_folio() can skip calling nfs_wb_folio() from kcompactd. Otherwise NFS can deadlock waiting for kcompactd enduced writeback which recurses back to NFS (which triggers writeback to NFSD via NFS loopback mount on the same host, NFSD blocks waiting for XFS's call to __filemap_get_folio): 6070.550357] INFO: task kcompactd0:58 blocked for more than 4435 seconds. {--- [58] "kcompactd0" [<0>] folio_wait_bit+0xe8/0x200 [<0>] folio_wait_writeback+0x2b/0x80 [<0>] nfs_wb_folio+0x80/0x1b0 [nfs] [<0>] nfs_release_folio+0x68/0x130 [nfs] [<0>] split_huge_page_to_list_to_order+0x362/0x840 [<0>] migrate_pages_batch+0x43d/0xb90 [<0>] migrate_pages_sync+0x9a/0x240 [<0>] migrate_pages+0x93c/0x9f0 [<0>] compact_zone+0x8e2/0x1030 [<0>] compact_node+0xdb/0x120 [<0>] kcompactd+0x121/0x2e0 [<0>] kthread+0xcf/0x100 [<0>] ret_from_fork+0x31/0x40 [<0>] ret_from_fork_asm+0x1a/0x30 ---} [akpm@linux-foundation.org: fix build] Link: https://lkml.kernel.org/r/20250225022002.26141-1-snitzer@kernel.org Fixes: 96780ca55e3c ("NFS: fix up nfs_release_folio() to try to release the page") Signed-off-by: Mike Snitzer <snitzer@kernel.org> Cc: Anna Schumaker <anna.schumaker@oracle.com> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-13dma: kmsan: export kmsan_handle_dma() for modulesSebastian Andrzej Siewior1-0/+1
commit 19fac3c93991502a22c5132824c40b6a2e64b136 upstream. kmsan_handle_dma() is used by virtio_ring() which can be built as a module. kmsan_handle_dma() needs to be exported otherwise building the virtio_ring fails. Export kmsan_handle_dma for modules. Link: https://lkml.kernel.org/r/20250218091411.MMS3wBN9@linutronix.de Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202502150634.qjxwSeJR-lkp@intel.com/ Fixes: 7ade4f10779c ("dma: kmsan: unpoison DMA mappings") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Macro Elver <elver@google.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-27mm,madvise,hugetlb: check for 0-length range after end address adjustmentRicardo Cañuelo Navarro1-1/+10
commit 2ede647a6fde3e54a6bfda7cf01c716649655900 upstream. Add a sanity check to madvise_dontneed_free() to address a corner case in madvise where a race condition causes the current vma being processed to be backed by a different page size. During a madvise(MADV_DONTNEED) call on a memory region registered with a userfaultfd, there's a period of time where the process mm lock is temporarily released in order to send a UFFD_EVENT_REMOVE and let userspace handle the event. During this time, the vma covering the current address range may change due to an explicit mmap done concurrently by another thread. If, after that change, the memory region, which was originally backed by 4KB pages, is now backed by hugepages, the end address is rounded down to a hugepage boundary to avoid data loss (see "Fixes" below). This rounding may cause the end address to be truncated to the same address as the start. Make this corner case follow the same semantics as in other similar cases where the requested region has zero length (ie. return 0). This will make madvise_walk_vmas() continue to the next vma in the range (this time holding the process mm lock) which, due to the prev pointer becoming stale because of the vma change, will be the same hugepage-backed vma that was just checked before. The next time madvise_dontneed_free() runs for this vma, if the start address isn't aligned to a hugepage boundary, it'll return -EINVAL, which is also in line with the madvise api. From userspace perspective, madvise() will return EINVAL because the start address isn't aligned according to the new vma alignment requirements (hugepage), even though it was correctly page-aligned when the call was issued. Link: https://lkml.kernel.org/r/20250203075206.1452208-1-rcn@igalia.com Fixes: 8ebe0a5eaaeb ("mm,madvise,hugetlb: fix unexpected data loss with MADV_DONTNEED on hugetlbfs") Signed-off-by: Ricardo Cañuelo Navarro <rcn@igalia.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Florent Revest <revest@google.com> Cc: Rik van Riel <riel@surriel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-27memcg: fix soft lockup in the OOM processChen Ridong2-2/+13
[ Upstream commit ade81479c7dda1ce3eedb215c78bc615bbd04f06 ] A soft lockup issue was found in the product with about 56,000 tasks were in the OOM cgroup, it was traversing them when the soft lockup was triggered. watchdog: BUG: soft lockup - CPU#2 stuck for 23s! [VM Thread:1503066] CPU: 2 PID: 1503066 Comm: VM Thread Kdump: loaded Tainted: G Hardware name: Huawei Cloud OpenStack Nova, BIOS RIP: 0010:console_unlock+0x343/0x540 RSP: 0000:ffffb751447db9a0 EFLAGS: 00000247 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 00000000ffffffff RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000247 RBP: ffffffffafc71f90 R08: 0000000000000000 R09: 0000000000000040 R10: 0000000000000080 R11: 0000000000000000 R12: ffffffffafc74bd0 R13: ffffffffaf60a220 R14: 0000000000000247 R15: 0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2fe6ad91f0 CR3: 00000004b2076003 CR4: 0000000000360ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vprintk_emit+0x193/0x280 printk+0x52/0x6e dump_task+0x114/0x130 mem_cgroup_scan_tasks+0x76/0x100 dump_header+0x1fe/0x210 oom_kill_process+0xd1/0x100 out_of_memory+0x125/0x570 mem_cgroup_out_of_memory+0xb5/0xd0 try_charge+0x720/0x770 mem_cgroup_try_charge+0x86/0x180 mem_cgroup_try_charge_delay+0x1c/0x40 do_anonymous_page+0xb5/0x390 handle_mm_fault+0xc4/0x1f0 This is because thousands of processes are in the OOM cgroup, it takes a long time to traverse all of them. As a result, this lead to soft lockup in the OOM process. To fix this issue, call 'cond_resched' in the 'mem_cgroup_scan_tasks' function per 1000 iterations. For global OOM, call 'touch_softlockup_watchdog' per 1000 iterations to avoid this issue. Link: https://lkml.kernel.org/r/20241224025238.3768787-1-chenridong@huaweicloud.com Fixes: 9cbb78bb3143 ("mm, memcg: introduce own oom handler to iterate only over its own threads") Signed-off-by: Chen Ridong <chenridong@huawei.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Shakeel Butt <shakeelb@google.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-27mm: update mark_victim tracepoints fieldsCarlos Galo1-1/+5
[ Upstream commit 72ba14deb40a9e9668ec5e66a341ed657e5215c2 ] The current implementation of the mark_victim tracepoint provides only the process ID (pid) of the victim process. This limitation poses challenges for userspace tools requiring real-time OOM analysis and intervention. Although this information is available from the kernel logs, it’s not the appropriate format to provide OOM notifications. In Android, BPF programs are used with the mark_victim trace events to notify userspace of an OOM kill. For consistency, update the trace event to include the same information about the OOMed victim as the kernel logs. - UID In Android each installed application has a unique UID. Including the `uid` assists in correlating OOM events with specific apps. - Process Name (comm) Enables identification of the affected process. - OOM Score Will allow userspace to get additional insight of the relative kill priority of the OOM victim. In Android, the oom_score_adj is used to categorize app state (foreground, background, etc.), which aids in analyzing user-perceptible impacts of OOM events [1]. - Total VM, RSS Stats, and pgtables Amount of memory used by the victim that will, potentially, be freed up by killing it. [1] https://cs.android.com/android/platform/superproject/main/+/246dc8fc95b6d93afcba5c6d6c133307abb3ac2e:frameworks/base/services/core/java/com/android/server/am/ProcessList.java;l=188-283 Signed-off-by: Carlos Galo <carlosgalo@google.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Stable-dep-of: ade81479c7dd ("memcg: fix soft lockup in the OOM process") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21mm: gup: fix infinite loop within __get_longterm_lockedZhaoyang Huang1-10/+4
commit 1aaf8c122918aa8897605a9aa1e8ed6600d6f930 upstream. We can run into an infinite loop in __get_longterm_locked() when collect_longterm_unpinnable_folios() finds only folios that are isolated from the LRU or were never added to the LRU. This can happen when all folios to be pinned are never added to the LRU, for example when vm_ops->fault allocated pages using cma_alloc() and never added them to the LRU. Fix it by simply taking a look at the list in the single caller, to see if anything was added. [zhaoyang.huang@unisoc.com: move definition of local] Link: https://lkml.kernel.org/r/20250122012604.3654667-1-zhaoyang.huang@unisoc.com Link: https://lkml.kernel.org/r/20250121020159.3636477-1-zhaoyang.huang@unisoc.com Fixes: 67e139b02d99 ("mm/gup.c: refactor check_and_migrate_movable_pages()") Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: David Hildenbrand <david@redhat.com> Suggested-by: David Hildenbrand <david@redhat.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Aijun Sun <aijun.sun@unisoc.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Wentao Guan <guanwentao@uniontech.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-17mm: kmemleak: fix upper boundary check for physical address objectsCatalin Marinas1-1/+1
commit 488b5b9eca68497b533ced059be5eff19578bbca upstream. Memblock allocations are registered by kmemleak separately, based on their physical address. During the scanning stage, it checks whether an object is within the min_low_pfn and max_low_pfn boundaries and ignores it otherwise. With the recent addition of __percpu pointer leak detection (commit 6c99d4eb7c5e ("kmemleak: enable tracking for percpu pointers")), kmemleak started reporting leaks in setup_zone_pageset() and setup_per_cpu_pageset(). These were caused by the node_data[0] object (initialised in alloc_node_data()) ending on the PFN_PHYS(max_low_pfn) boundary. The non-strict upper boundary check introduced by commit 84c326299191 ("mm: kmemleak: check physical address when scan") causes the pg_data_t object to be ignored (not scanned) and the __percpu pointers it contains to be reported as leaks. Make the max_low_pfn upper boundary check strict when deciding whether to ignore a physical address object and not scan it. Link: https://lkml.kernel.org/r/20250127184233.2974311-1-catalin.marinas@arm.com Fixes: 84c326299191 ("mm: kmemleak: check physical address when scan") Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Jakub Kicinski <kuba@kernel.org> Tested-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Cc: Patrick Wang <patrick.wang.shcn@gmail.com> Cc: <stable@vger.kernel.org> [6.0.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-17kfence: skip __GFP_THISNODE allocations on NUMA systemsMarco Elver1-0/+2
commit e64f81946adf68cd75e2207dd9a51668348a4af8 upstream. On NUMA systems, __GFP_THISNODE indicates that an allocation _must_ be on a particular node, and failure to allocate on the desired node will result in a failed allocation. Skip __GFP_THISNODE allocations if we are running on a NUMA system, since KFENCE can't guarantee which node its pool pages are allocated on. Link: https://lkml.kernel.org/r/20250124120145.410066-1-elver@google.com Fixes: 236e9f153852 ("kfence: skip all GFP_ZONEMASK allocations") Signed-off-by: Marco Elver <elver@google.com> Reported-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: Alexander Potapenko <glider@google.com> Cc: Chistoph Lameter <cl@linux.com> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-01cachestat: fix page cache statistics permission checkingLinus Torvalds1-0/+19
commit 5f537664e705b0bf8b7e329861f20128534f6a83 upstream. When the 'cachestat()' system call was added in commit cf264e1329fb ("cachestat: implement cachestat syscall"), it was meant to be a much more convenient (and performant) version of mincore() that didn't need mapping things into the user virtual address space in order to work. But it ended up missing the "check for writability or ownership" fix for mincore(), done in commit 134fca9063ad ("mm/mincore.c: make mincore() more conservative"). This just adds equivalent logic to 'cachestat()', modified for the file context (rather than vma). Reported-by: Sudheendra Raghav Neela <sneela@tugraz.at> Fixes: cf264e1329fb ("cachestat: implement cachestat syscall") Tested-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-01Revert "libfs: Add simple_offset_empty()"Chuck Lever1-2/+2
[ Upstream commit d7bde4f27ceef3dc6d72010a20d4da23db835a32 ] simple_empty() and simple_offset_empty() perform the same task. The latter's use as a canary to find bugs has not found any new issues. A subsequent patch will remove the use of the mtree for iterating directory contents, so revert back to using a similar mechanism for determining whether a directory is indeed empty. Only one such mechanism is ever needed. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Link: https://lore.kernel.org/r/20241228175522.1854234-3-cel@kernel.org Reviewed-by: Yang Erkun <yangerkun@huawei.com> Signed-off-by: Christian Brauner <brauner@kernel.org> [ cel: adjusted to apply to origin/linux-6.6.y ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-01libfs: Add simple_offset_rename() APIChuck Lever1-2/+1
[ Upstream commit 5a1a25be995e1014abd01600479915683e356f5c ] I'm about to fix a tmpfs rename bug that requires the use of internal simple_offset helpers that are not available in mm/shmem.c Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Link: https://lore.kernel.org/r/20240415152057.4605-3-cel@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-01libfs: Add simple_offset_empty()Chuck Lever1-2/+2
[ Upstream commit ecba88a3b32d733d41e27973e25b2bc580f64281 ] For simple filesystems that use directory offset mapping, rely strictly on the directory offset map to tell when a directory has no children. After this patch is applied, the emptiness test holds only the RCU read lock when the directory being tested has no children. In addition, this adds another layer of confirmation that simple_offset_add/remove() are working as expected. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Link: https://lore.kernel.org/r/170820143463.6328.7872919188371286951.stgit@91.116.238.104.host.secureserver.net Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 5a1a25be995e ("libfs: Add simple_offset_rename() API") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-23filemap: avoid truncating 64-bit offset to 32 bitsMarco Nelissen1-1/+1
commit f505e6c91e7a22d10316665a86d79f84d9f0ba76 upstream. On 32-bit kernels, folio_seek_hole_data() was inadvertently truncating a 64-bit value to 32 bits, leading to a possible infinite loop when writing to an xfs filesystem. Link: https://lkml.kernel.org/r/20250102190540.1356838-1-marco.nelissen@gmail.com Fixes: 54fa39ac2e00 ("iomap: use mapping_seek_hole_data") Signed-off-by: Marco Nelissen <marco.nelissen@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-17mm: hugetlb: independent PMD page table shared countLiu Shixin1-9/+7
[ Upstream commit 59d9094df3d79443937add8700b2ef1a866b1081 ] The folio refcount may be increased unexpectly through try_get_folio() by caller such as split_huge_pages. In huge_pmd_unshare(), we use refcount to check whether a pmd page table is shared. The check is incorrect if the refcount is increased by the above caller, and this can cause the page table leaked: BUG: Bad page state in process sh pfn:109324 page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x66 pfn:0x109324 flags: 0x17ffff800000000(node=0|zone=2|lastcpupid=0xfffff) page_type: f2(table) raw: 017ffff800000000 0000000000000000 0000000000000000 0000000000000000 raw: 0000000000000066 0000000000000000 00000000f2000000 0000000000000000 page dumped because: nonzero mapcount ... CPU: 31 UID: 0 PID: 7515 Comm: sh Kdump: loaded Tainted: G B 6.13.0-rc2master+ #7 Tainted: [B]=BAD_PAGE Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 Call trace: show_stack+0x20/0x38 (C) dump_stack_lvl+0x80/0xf8 dump_stack+0x18/0x28 bad_page+0x8c/0x130 free_page_is_bad_report+0xa4/0xb0 free_unref_page+0x3cc/0x620 __folio_put+0xf4/0x158 split_huge_pages_all+0x1e0/0x3e8 split_huge_pages_write+0x25c/0x2d8 full_proxy_write+0x64/0xd8 vfs_write+0xcc/0x280 ksys_write+0x70/0x110 __arm64_sys_write+0x24/0x38 invoke_syscall+0x50/0x120 el0_svc_common.constprop.0+0xc8/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x34/0x128 el0t_64_sync_handler+0xc8/0xd0 el0t_64_sync+0x190/0x198 The issue may be triggered by damon, offline_page, page_idle, etc, which will increase the refcount of page table. 1. The page table itself will be discarded after reporting the "nonzero mapcount". 2. The HugeTLB page mapped by the page table miss freeing since we treat the page table as shared and a shared page table will not be unmapped. Fix it by introducing independent PMD page table shared count. As described by comment, pt_index/pt_mm/pt_frag_refcount are used for s390 gmap, x86 pgds and powerpc, pt_share_count is used for x86/arm64/riscv pmds, so we can reuse the field as pt_share_count. Link: https://lkml.kernel.org/r/20241216071147.3984217-1-liushixin2@huawei.com Fixes: 39dde65c9940 ("[PATCH] shared page table for hugetlb page") Signed-off-by: Liu Shixin <liushixin2@huawei.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Ken Chen <kenneth.w.chen@intel.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-17mm/hugetlb: enforce that PMD PT sharing has split PMD PT locksDavid Hildenbrand1-4/+4
[ Upstream commit 188cac58a8bcdf82c7f63275b68f7a46871e45d6 ] Sharing page tables between processes but falling back to per-MM page table locks cannot possibly work. So, let's make sure that we do have split PMD locks by adding a new Kconfig option and letting that depend on CONFIG_SPLIT_PMD_PTLOCKS. Link: https://lkml.kernel.org/r/20240726150728.3159964-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <muchun.song@linux.dev> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Stable-dep-of: 59d9094df3d7 ("mm: hugetlb: independent PMD page table shared count") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-17memblock: use numa_valid_node() helper to check for invalid node IDMike Rapoport (IBM)1-21/+7
commit 8043832e2a123fd9372007a29192f2f3ba328cd6 upstream. Introduce numa_valid_node(nid) that verifies that nid is a valid node ID and use that instead of comparing nid parameter with either NUMA_NO_NODE or MAX_NUMNODES. This makes the checks for valid node IDs consistent and more robust and allows to get rid of multiple WARNings. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-17memblock: make memblock_set_node() also warn about use of MAX_NUMNODESJan Beulich1-0/+4
[ Upstream commit e0eec24e2e199873f43df99ec39773ad3af2bff7 ] On an (old) x86 system with SRAT just covering space above 4Gb: ACPI: SRAT: Node 0 PXM 0 [mem 0x100000000-0xfffffffff] hotplug the commit referenced below leads to this NUMA configuration no longer being refused by a CONFIG_NUMA=y kernel (previously NUMA: nodes only cover 6144MB of your 8185MB e820 RAM. Not used. No NUMA configuration found Faking a node at [mem 0x0000000000000000-0x000000027fffffff] was seen in the log directly after the message quoted above), because of memblock_validate_numa_coverage() checking for NUMA_NO_NODE (only). This in turn led to memblock_alloc_range_nid()'s warning about MAX_NUMNODES triggering, followed by a NULL deref in memmap_init() when trying to access node 64's (NODE_SHIFT=6) node data. To compensate said change, make memblock_set_node() warn on and adjust a passed in value of MAX_NUMNODES, just like various other functions already do. Fixes: ff6c3d81f2e8 ("NUMA: optimize detection of memory with no node id assigned by firmware") Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/1c8a058c-5365-4f27-a9f1-3aeb7fb3e7b2@suse.com Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-09mm: vmscan: account for free pages to prevent infinite Loop in ↵Seiji Nishikawa1-1/+8
throttle_direct_reclaim() commit 6aaced5abd32e2a57cd94fd64f824514d0361da8 upstream. The task sometimes continues looping in throttle_direct_reclaim() because allow_direct_reclaim(pgdat) keeps returning false. #0 [ffff80002cb6f8d0] __switch_to at ffff8000080095ac #1 [ffff80002cb6f900] __schedule at ffff800008abbd1c #2 [ffff80002cb6f990] schedule at ffff800008abc50c #3 [ffff80002cb6f9b0] throttle_direct_reclaim at ffff800008273550 #4 [ffff80002cb6fa20] try_to_free_pages at ffff800008277b68 #5 [ffff80002cb6fae0] __alloc_pages_nodemask at ffff8000082c4660 #6 [ffff80002cb6fc50] alloc_pages_vma at ffff8000082e4a98 #7 [ffff80002cb6fca0] do_anonymous_page at ffff80000829f5a8 #8 [ffff80002cb6fce0] __handle_mm_fault at ffff8000082a5974 #9 [ffff80002cb6fd90] handle_mm_fault at ffff8000082a5bd4 At this point, the pgdat contains the following two zones: NODE: 4 ZONE: 0 ADDR: ffff00817fffe540 NAME: "DMA32" SIZE: 20480 MIN/LOW/HIGH: 11/28/45 VM_STAT: NR_FREE_PAGES: 359 NR_ZONE_INACTIVE_ANON: 18813 NR_ZONE_ACTIVE_ANON: 0 NR_ZONE_INACTIVE_FILE: 50 NR_ZONE_ACTIVE_FILE: 0 NR_ZONE_UNEVICTABLE: 0 NR_ZONE_WRITE_PENDING: 0 NR_MLOCK: 0 NR_BOUNCE: 0 NR_ZSPAGES: 0 NR_FREE_CMA_PAGES: 0 NODE: 4 ZONE: 1 ADDR: ffff00817fffec00 NAME: "Normal" SIZE: 8454144 PRESENT: 98304 MIN/LOW/HIGH: 68/166/264 VM_STAT: NR_FREE_PAGES: 146 NR_ZONE_INACTIVE_ANON: 94668 NR_ZONE_ACTIVE_ANON: 3 NR_ZONE_INACTIVE_FILE: 735 NR_ZONE_ACTIVE_FILE: 78 NR_ZONE_UNEVICTABLE: 0 NR_ZONE_WRITE_PENDING: 0 NR_MLOCK: 0 NR_BOUNCE: 0 NR_ZSPAGES: 0 NR_FREE_CMA_PAGES: 0 In allow_direct_reclaim(), while processing ZONE_DMA32, the sum of inactive/active file-backed pages calculated in zone_reclaimable_pages() based on the result of zone_page_state_snapshot() is zero. Additionally, since this system lacks swap, the calculation of inactive/ active anonymous pages is skipped. crash> p nr_swap_pages nr_swap_pages = $1937 = { counter = 0 } As a result, ZONE_DMA32 is deemed unreclaimable and skipped, moving on to the processing of the next zone, ZONE_NORMAL, despite ZONE_DMA32 having free pages significantly exceeding the high watermark. The problem is that the pgdat->kswapd_failures hasn't been incremented. crash> px ((struct pglist_data *) 0xffff00817fffe540)->kswapd_failures $1935 = 0x0 This is because the node deemed balanced. The node balancing logic in balance_pgdat() evaluates all zones collectively. If one or more zones (e.g., ZONE_DMA32) have enough free pages to meet their watermarks, the entire node is deemed balanced. This causes balance_pgdat() to exit early before incrementing the kswapd_failures, as it considers the overall memory state acceptable, even though some zones (like ZONE_NORMAL) remain under significant pressure. The patch ensures that zone_reclaimable_pages() includes free pages (NR_FREE_PAGES) in its calculation when no other reclaimable pages are available (e.g., file-backed or anonymous pages). This change prevents zones like ZONE_DMA32, which have sufficient free pages, from being mistakenly deemed unreclaimable. By doing so, the patch ensures proper node balancing, avoids masking pressure on other zones like ZONE_NORMAL, and prevents infinite loops in throttle_direct_reclaim() caused by allow_direct_reclaim(pgdat) repeatedly returning false. The kernel hangs due to a task stuck in throttle_direct_reclaim(), caused by a node being incorrectly deemed balanced despite pressure in certain zones, such as ZONE_NORMAL. This issue arises from zone_reclaimable_pages() returning 0 for zones without reclaimable file- backed or anonymous pages, causing zones like ZONE_DMA32 with sufficient free pages to be skipped. The lack of swap or reclaimable pages results in ZONE_DMA32 being ignored during reclaim, masking pressure in other zones. Consequently, pgdat->kswapd_failures remains 0 in balance_pgdat(), preventing fallback mechanisms in allow_direct_reclaim() from being triggered, leading to an infinite loop in throttle_direct_reclaim(). This patch modifies zone_reclaimable_pages() to account for free pages (NR_FREE_PAGES) when no other reclaimable pages exist. This ensures zones with sufficient free pages are not skipped, enabling proper balancing and reclaim behavior. [akpm@linux-foundation.org: coding-style cleanups] Link: https://lkml.kernel.org/r/20241130164346.436469-1-snishika@redhat.com Link: https://lkml.kernel.org/r/20241130161236.433747-2-snishika@redhat.com Fixes: 5a1c84b404a7 ("mm: remove reclaim and compaction retry approximations") Signed-off-by: Seiji Nishikawa <snishika@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-09mm/kmemleak: fix sleeping function called from invalid context at print messageAlessandro Carminati1-1/+1
commit cddc76b165161a02ff14c4d84d0f5266d9d32b9e upstream. Address a bug in the kernel that triggers a "sleeping function called from invalid context" warning when /sys/kernel/debug/kmemleak is printed under specific conditions: - CONFIG_PREEMPT_RT=y - Set SELinux as the LSM for the system - Set kptr_restrict to 1 - kmemleak buffer contains at least one item BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 136, name: cat preempt_count: 1, expected: 0 RCU nest depth: 2, expected: 2 6 locks held by cat/136: #0: ffff32e64bcbf950 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xb8/0xe30 #1: ffffafe6aaa9dea0 (scan_mutex){+.+.}-{3:3}, at: kmemleak_seq_start+0x34/0x128 #3: ffff32e6546b1cd0 (&object->lock){....}-{2:2}, at: kmemleak_seq_show+0x3c/0x1e0 #4: ffffafe6aa8d8560 (rcu_read_lock){....}-{1:2}, at: has_ns_capability_noaudit+0x8/0x1b0 #5: ffffafe6aabbc0f8 (notif_lock){+.+.}-{2:2}, at: avc_compute_av+0xc4/0x3d0 irq event stamp: 136660 hardirqs last enabled at (136659): [<ffffafe6a80fd7a0>] _raw_spin_unlock_irqrestore+0xa8/0xd8 hardirqs last disabled at (136660): [<ffffafe6a80fd85c>] _raw_spin_lock_irqsave+0x8c/0xb0 softirqs last enabled at (0): [<ffffafe6a5d50b28>] copy_process+0x11d8/0x3df8 softirqs last disabled at (0): [<0000000000000000>] 0x0 Preemption disabled at: [<ffffafe6a6598a4c>] kmemleak_seq_show+0x3c/0x1e0 CPU: 1 UID: 0 PID: 136 Comm: cat Tainted: G E 6.11.0-rt7+ #34 Tainted: [E]=UNSIGNED_MODULE Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0xa0/0x128 show_stack+0x1c/0x30 dump_stack_lvl+0xe8/0x198 dump_stack+0x18/0x20 rt_spin_lock+0x8c/0x1a8 avc_perm_nonode+0xa0/0x150 cred_has_capability.isra.0+0x118/0x218 selinux_capable+0x50/0x80 security_capable+0x7c/0xd0 has_ns_capability_noaudit+0x94/0x1b0 has_capability_noaudit+0x20/0x30 restricted_pointer+0x21c/0x4b0 pointer+0x298/0x760 vsnprintf+0x330/0xf70 seq_printf+0x178/0x218 print_unreferenced+0x1a4/0x2d0 kmemleak_seq_show+0xd0/0x1e0 seq_read_iter+0x354/0xe30 seq_read+0x250/0x378 full_proxy_read+0xd8/0x148 vfs_read+0x190/0x918 ksys_read+0xf0/0x1e0 __arm64_sys_read+0x70/0xa8 invoke_syscall.constprop.0+0xd4/0x1d8 el0_svc+0x50/0x158 el0t_64_sync+0x17c/0x180 %pS and %pK, in the same back trace line, are redundant, and %pS can void %pK service in certain contexts. %pS alone already provides the necessary information, and if it cannot resolve the symbol, it falls back to printing the raw address voiding the original intent behind the %pK. Additionally, %pK requires a privilege check CAP_SYSLOG enforced through the LSM, which can trigger a "sleeping function called from invalid context" warning under RT_PREEMPT kernels when the check occurs in an atomic context. This issue may also affect other LSMs. This change avoids the unnecessary privilege check and resolves the sleeping function warning without any loss of information. Link: https://lkml.kernel.org/r/20241217142032.55793-1-acarmina@redhat.com Fixes: 3a6f33d86baa ("mm/kmemleak: use %pK to display kernel pointers in backtrace") Signed-off-by: Alessandro Carminati <acarmina@redhat.com> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Clément Léger <clement.leger@bootlin.com> Cc: Alessandro Carminati <acarmina@redhat.com> Cc: Eric Chanudet <echanude@redhat.com> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-09mm/readahead: fix large folio support in async readaheadYafang Shao1-1/+5
commit 158cdce87c8c172787063998ad5dd3e2f658b963 upstream. When testing large folio support with XFS on our servers, we observed that only a few large folios are mapped when reading large files via mmap. After a thorough analysis, I identified it was caused by the `/sys/block/*/queue/read_ahead_kb` setting. On our test servers, this parameter is set to 128KB. After I tune it to 2MB, the large folio can work as expected. However, I believe the large folio behavior should not be dependent on the value of read_ahead_kb. It would be more robust if the kernel can automatically adopt to it. With /sys/block/*/queue/read_ahead_kb set to 128KB and performing a sequential read on a 1GB file using MADV_HUGEPAGE, the differences in /proc/meminfo are as follows: - before this patch FileHugePages: 18432 kB FilePmdMapped: 4096 kB - after this patch FileHugePages: 1067008 kB FilePmdMapped: 1048576 kB This shows that after applying the patch, the entire 1GB file is mapped to huge pages. The stable list is CCed, as without this patch, large folios don't function optimally in the readahead path. It's worth noting that if read_ahead_kb is set to a larger value that isn't aligned with huge page sizes (e.g., 4MB + 128KB), it may still fail to map to hugepages. Link: https://lkml.kernel.org/r/20241108141710.9721-1-laoar.shao@gmail.com Link: https://lkml.kernel.org/r/20241206083025.3478-1-laoar.shao@gmail.com Fixes: 4687fdbb805a ("mm/filemap: Support VM_HUGEPAGE for file mappings") Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Tested-by: kernel test robot <oliver.sang@intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-09memblock: allow zero threshold in validate_numa_converage()Mike Rapoport (Microsoft)1-2/+2
[ Upstream commit 9cdc6423acb49055efb444ecd895d853a70ef931 ] Currently memblock validate_numa_converage() returns false negative when threshold set to zero. Make the check if the memory size with invalid node ID is greater than the threshold exclusive to fix that. Link: https://lore.kernel.org/all/Z0mIDBD4KLyxyOCm@kernel.org/ Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-09NUMA: optimize detection of memory with no node id assigned by firmwareLiam Ni1-0/+34
[ Upstream commit ff6c3d81f2e86b63a3a530683f89ef393882782a ] Sanity check that makes sure the nodes cover all memory loops over numa_meminfo to count the pages that have node id assigned by the firmware, then loops again over memblock.memory to find the total amount of memory and in the end checks that the difference between the total memory and memory that covered by nodes is less than some threshold. Worse, the loop over numa_meminfo calls __absent_pages_in_range() that also partially traverses memblock.memory. It's much simpler and more efficient to have a single traversal of memblock.memory that verifies that amount of memory not covered by nodes is less than a threshold. Introduce memblock_validate_numa_coverage() that does exactly that and use it instead of numa_meminfo_cover_memory(). Link: https://lkml.kernel.org/r/20231026020329.327329-1-zhiguangni01@gmail.com Signed-off-by: Liam Ni <zhiguangni01@gmail.com> Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Bibo Mao <maobibo@loongson.cn> Cc: Binbin Zhou <zhoubinbin@loongson.cn> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Feiyang Chen <chenfeiyang@loongson.cn> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: WANG Xuerui <kernel@xen0n.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Stable-dep-of: 9cdc6423acb4 ("memblock: allow zero threshold in validate_numa_converage()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-27vmalloc: fix accounting with i915Matthew Wilcox (Oracle)1-2/+4
commit a2e740e216f5bf49ccb83b6d490c72a340558a43 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-14mm/damon/vaddr: fix issue in damon_va_evenly_split_region()Zheng Yejian2-2/+3
commit f3c7a1ede435e2e45177d7a490a85fb0a0ec96d1 upstream. Patch series "mm/damon/vaddr: Fix issue in damon_va_evenly_split_region()". v2. According to the logic of damon_va_evenly_split_region(), currently following split case would not meet the expectation: Suppose DAMON_MIN_REGION=0x1000, Case: Split [0x0, 0x3000) into 2 pieces, then the result would be acutually 3 regions: [0x0, 0x1000), [0x1000, 0x2000), [0x2000, 0x3000) but NOT the expected 2 regions: [0x0, 0x1000), [0x1000, 0x3000) !!! The root cause is that when calculating size of each split piece in damon_va_evenly_split_region(): `sz_piece = ALIGN_DOWN(sz_orig / nr_pieces, DAMON_MIN_REGION);` both the dividing and the ALIGN_DOWN may cause loss of precision, then each time split one piece of size 'sz_piece' from origin 'start' to 'end' would cause more pieces are split out than expected!!! To fix it, count for each piece split and make sure no more than 'nr_pieces'. In addition, add above case into damon_test_split_evenly(). And add 'nr_piece == 1' check in damon_va_evenly_split_region() for better code readability and add a corresponding kunit testcase. This patch (of 2): According to the logic of damon_va_evenly_split_region(), currently following split case would not meet the expectation: Suppose DAMON_MIN_REGION=0x1000, Case: Split [0x0, 0x3000) into 2 pieces, then the result would be acutually 3 regions: [0x0, 0x1000), [0x1000, 0x2000), [0x2000, 0x3000) but NOT the expected 2 regions: [0x0, 0x1000), [0x1000, 0x3000) !!! The root cause is that when calculating size of each split piece in damon_va_evenly_split_region(): `sz_piece = ALIGN_DOWN(sz_orig / nr_pieces, DAMON_MIN_REGION);` both the dividing and the ALIGN_DOWN may cause loss of precision, then each time split one piece of size 'sz_piece' from origin 'start' to 'end' would cause more pieces are split out than expected!!! To fix it, count for each piece split and make sure no more than 'nr_pieces'. In addition, add above case into damon_test_split_evenly(). After this patch, damon-operations test passed: # ./tools/testing/kunit/kunit.py run damon-operations [...] ============== damon-operations (6 subtests) =============== [PASSED] damon_test_three_regions_in_vmas [PASSED] damon_test_apply_three_regions1 [PASSED] damon_test_apply_three_regions2 [PASSED] damon_test_apply_three_regions3 [PASSED] damon_test_apply_three_regions4 [PASSED] damon_test_split_evenly ================ [PASSED] damon-operations ================= Link: https://lkml.kernel.org/r/20241022083927.3592237-1-zhengyejian@huaweicloud.com Link: https://lkml.kernel.org/r/20241022083927.3592237-2-zhengyejian@huaweicloud.com Fixes: 3f49584b262c ("mm/damon: implement primitives for the virtual memory address spaces") Signed-off-by: Zheng Yejian <zhengyejian@huaweicloud.com> Reviewed-by: SeongJae Park <sj@kernel.org> Cc: Fernand Sieber <sieberf@amazon.com> Cc: Leonard Foerster <foersleo@amazon.de> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Ye Weihua <yeweihua4@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-14mm/mempolicy: fix migrate_to_node() assuming there is at least one VMA in a MMDavid Hildenbrand1-0/+4
[ Upstream commit 091c1dd2d4df6edd1beebe0e5863d4034ade9572 ] We currently assume that there is at least one VMA in a MM, which isn't true. So we might end up having find_vma() return NULL, to then de-reference NULL. So properly handle find_vma() returning NULL. This fixes the report: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 UID: 0 PID: 6021 Comm: syz-executor284 Not tainted 6.12.0-rc7-syzkaller-00187-gf868cd251776 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:migrate_to_node mm/mempolicy.c:1090 [inline] RIP: 0010:do_migrate_pages+0x403/0x6f0 mm/mempolicy.c:1194 Code: ... RSP: 0018:ffffc9000375fd08 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffc9000375fd78 RCX: 0000000000000000 RDX: ffff88807e171300 RSI: dffffc0000000000 RDI: ffff88803390c044 RBP: ffff88807e171428 R08: 0000000000000014 R09: fffffbfff2039ef1 R10: ffffffff901cf78f R11: 0000000000000000 R12: 0000000000000003 R13: ffffc9000375fe90 R14: ffffc9000375fe98 R15: ffffc9000375fdf8 FS: 00005555919e1380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555919e1ca8 CR3: 000000007f12a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> kernel_migrate_pages+0x5b2/0x750 mm/mempolicy.c:1709 __do_sys_migrate_pages mm/mempolicy.c:1727 [inline] __se_sys_migrate_pages mm/mempolicy.c:1723 [inline] __x64_sys_migrate_pages+0x96/0x100 mm/mempolicy.c:1723 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f [akpm@linux-foundation.org: add unlikely()] Link: https://lkml.kernel.org/r/20241120201151.9518-1-david@redhat.com Fixes: 39743889aaf7 ("[PATCH] Swap Migration V5: sys_migrate_pages interface") Signed-off-by: David Hildenbrand <david@redhat.com> Reported-by: syzbot+3511625422f7aa637f0d@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/673d2696.050a0220.3c9d61.012f.GAE@google.com/T/ Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Reviewed-by: Christoph Lameter <cl@linux.com> Cc: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14mempolicy: fix migrate_pages(2) syscall return nr_failedHugh Dickins1-179/+159
[ Upstream commit 1cb5d11a370f661c5d0d888bb0cfc2cdc5791382 ] "man 2 migrate_pages" says "On success migrate_pages() returns the number of pages that could not be moved". Although 5.3 and 5.4 commits fixed mbind(MPOL_MF_STRICT|MPOL_MF_MOVE*) to fail with EIO when not all pages could be moved (because some could not be isolated for migration), migrate_pages(2) was left still reporting only those pages failing at the migration stage, forgetting those failing at the earlier isolation stage. Fix that by accumulating a long nr_failed count in struct queue_pages, returned by queue_pages_range() when it's not returning an error, for adding on to the nr_failed count from migrate_pages() in mm/migrate.c. A count of pages? It's more a count of folios, but changing it to pages would entail more work (also in mm/migrate.c): does not seem justified. queue_pages_range() itself should only return -EIO in the "strictly unmovable" case (STRICT without any MOVEs): in that case it's best to break out as soon as nr_failed gets set; but otherwise it should continue to isolate pages for MOVing even when nr_failed - as the mbind(2) manpage promises. There's a case when nr_failed should be incremented when it was missed: queue_folios_pte_range() and queue_folios_hugetlb() count the transient migration entries, like queue_folios_pmd() already did. And there's a case when nr_failed should not be incremented when it would have been: in meeting later PTEs of the same large folio, which can only be isolated once: fixed by recording the current large folio in struct queue_pages. Clean up the affected functions, fixing or updating many comments. Bool migrate_folio_add(), without -EIO: true if adding, or if skipping shared (but its arguable folio_estimated_sharers() heuristic left unchanged). Use MPOL_MF_WRLOCK flag to queue_pages_range(), instead of bool lock_vma. Use explicit STRICT|MOVE* flags where queue_pages_test_walk() checks for skipping, instead of hiding them behind MPOL_MF_VALID. Link: https://lkml.kernel.org/r/9a6b0b9-3bb-dbef-8adf-efab4397b8d@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Stable-dep-of: 091c1dd2d4df ("mm/mempolicy: fix migrate_to_node() assuming there is at least one VMA in a MM") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14kasan: make report_lock a raw spinlockJared Kangas1-3/+3
commit e30a0361b8515d424c73c67de1a43e45a13b8ba2 upstream. If PREEMPT_RT is enabled, report_lock is a sleeping spinlock and must not be locked when IRQs are disabled. However, KASAN reports may be triggered in such contexts. For example: char *s = kzalloc(1, GFP_KERNEL); kfree(s); local_irq_disable(); char c = *s; /* KASAN report here leads to spin_lock() */ local_irq_enable(); Make report_spinlock a raw spinlock to prevent rescheduling when PREEMPT_RT is enabled. Link: https://lkml.kernel.org/r/20241119210234.1602529-1-jkangas@redhat.com Fixes: 342a93247e08 ("locking/spinlock: Provide RT variant header: <linux/spinlock_rt.h>") Signed-off-by: Jared Kangas <jkangas@redhat.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-14mm: page_alloc: move mlocked flag clearance into free_pages_prepare()Roman Gushchin2-20/+15
commit 66edc3a5894c74f8887c8af23b97593a0dd0df4d upstream. Syzbot reported a bad page state problem caused by a page being freed using free_page() still having a mlocked flag at free_pages_prepare() stage: BUG: Bad page state in process syz.5.504 pfn:61f45 page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x61f45 flags: 0xfff00000080204(referenced|workingset|mlocked|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000080204 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x400dc0(GFP_KERNEL_ACCOUNT|__GFP_ZERO), pid 8443, tgid 8442 (syz.5.504), ts 201884660643, free_ts 201499827394 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x303f/0x3190 mm/page_alloc.c:3457 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 kvm_coalesced_mmio_init+0x1f/0xf0 virt/kvm/coalesced_mmio.c:99 kvm_create_vm virt/kvm/kvm_main.c:1235 [inline] kvm_dev_ioctl_create_vm virt/kvm/kvm_main.c:5488 [inline] kvm_dev_ioctl+0x12dc/0x2240 virt/kvm/kvm_main.c:5530 __do_compat_sys_ioctl fs/ioctl.c:1007 [inline] __se_compat_sys_ioctl+0x510/0xc90 fs/ioctl.c:950 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e page last free pid 8399 tgid 8399 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_folios+0xf12/0x18d0 mm/page_alloc.c:2686 folios_put_refs+0x76c/0x860 mm/swap.c:1007 free_pages_and_swap_cache+0x5c8/0x690 mm/swap_state.c:335 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline] tlb_batch_pages_flush mm/mmu_gather.c:149 [inline] tlb_flush_mmu_free mm/mmu_gather.c:366 [inline] tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:465 exit_mmap+0x496/0xc40 mm/mmap.c:1926 __mmput+0x115/0x390 kernel/fork.c:1348 exit_mm+0x220/0x310 kernel/exit.c:571 do_exit+0x9b2/0x28e0 kernel/exit.c:926 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 __do_sys_exit_group kernel/exit.c:1099 [inline] __se_sys_exit_group kernel/exit.c:1097 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Modules linked in: CPU: 0 UID: 0 PID: 8442 Comm: syz.5.504 Not tainted 6.12.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 bad_page+0x176/0x1d0 mm/page_alloc.c:501 free_page_is_bad mm/page_alloc.c:918 [inline] free_pages_prepare mm/page_alloc.c:1100 [inline] free_unref_page+0xed0/0xf20 mm/page_alloc.c:2638 kvm_destroy_vm virt/kvm/kvm_main.c:1327 [inline] kvm_put_kvm+0xc75/0x1350 virt/kvm/kvm_main.c:1386 kvm_vcpu_release+0x54/0x60 virt/kvm/kvm_main.c:4143 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xa2f/0x28e0 kernel/exit.c:939 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 __do_sys_exit_group kernel/exit.c:1099 [inline] __se_sys_exit_group kernel/exit.c:1097 [inline] __ia32_sys_exit_group+0x3f/0x40 kernel/exit.c:1097 ia32_sys_call+0x2624/0x2630 arch/x86/include/generated/asm/syscalls_32.h:253 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf745d579 Code: Unable to access opcode bytes at 0xf745d54f. RSP: 002b:00000000f75afd6c EFLAGS: 00000206 ORIG_RAX: 00000000000000fc RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 00000000ffffff9c RDI: 00000000f744cff4 RBP: 00000000f717ae61 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> The problem was originally introduced by commit b109b87050df ("mm/munlock: replace clear_page_mlock() by final clearance"): it was focused on handling pagecache and anonymous memory and wasn't suitable for lower level get_page()/free_page() API's used for example by KVM, as with this reproducer. Fix it by moving the mlocked flag clearance down to free_page_prepare(). The bug itself if fairly old and harmless (aside from generating these warnings), aside from a small memory leak - "bad" pages are stopped from being allocated again. Link: https://lkml.kernel.org/r/20241106195354.270757-1-roman.gushchin@linux.dev Fixes: b109b87050df ("mm/munlock: replace clear_page_mlock() by final clearance") Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev> Reported-by: syzbot+e985d3026c4fd041578e@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/6729f475.050a0220.701a.0019.GAE@google.com Acked-by: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Sean Christopherson <seanjc@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09mm/slub: Avoid list corruption when removing a slab from the full listyuan.gao2-1/+13
commit dbc16915279a548a204154368da23d402c141c81 upstream. Boot with slub_debug=UFPZ. If allocated object failed in alloc_consistency_checks, all objects of the slab will be marked as used, and then the slab will be removed from the partial list. When an object belonging to the slab got freed later, the remove_full() function is called. Because the slab is neither on the partial list nor on the full list, it eventually lead to a list corruption (actually a list poison being detected). So we need to mark and isolate the slab page with metadata corruption, do not put it back in circulation. Because the debug caches avoid all the fastpaths, reusing the frozen bit to mark slab page with metadata corruption seems to be fine. [ 4277.385669] list_del corruption, ffffea00044b3e50->next is LIST_POISON1 (dead000000000100) [ 4277.387023] ------------[ cut here ]------------ [ 4277.387880] kernel BUG at lib/list_debug.c:56! [ 4277.388680] invalid opcode: 0000 [#1] PREEMPT SMP PTI [ 4277.389562] CPU: 5 PID: 90 Comm: kworker/5:1 Kdump: loaded Tainted: G OE 6.6.1-1 #1 [ 4277.392113] Workqueue: xfs-inodegc/vda1 xfs_inodegc_worker [xfs] [ 4277.393551] RIP: 0010:__list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.394518] Code: 48 91 82 e8 37 f9 9a ff 0f 0b 48 89 fe 48 c7 c7 28 49 91 82 e8 26 f9 9a ff 0f 0b 48 89 fe 48 c7 c7 58 49 91 [ 4277.397292] RSP: 0018:ffffc90000333b38 EFLAGS: 00010082 [ 4277.398202] RAX: 000000000000004e RBX: ffffea00044b3e50 RCX: 0000000000000000 [ 4277.399340] RDX: 0000000000000002 RSI: ffffffff828f8715 RDI: 00000000ffffffff [ 4277.400545] RBP: ffffea00044b3e40 R08: 0000000000000000 R09: ffffc900003339f0 [ 4277.401710] R10: 0000000000000003 R11: ffffffff82d44088 R12: ffff888112cf9910 [ 4277.402887] R13: 0000000000000001 R14: 0000000000000001 R15: ffff8881000424c0 [ 4277.404049] FS: 0000000000000000(0000) GS:ffff88842fd40000(0000) knlGS:0000000000000000 [ 4277.405357] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4277.406389] CR2: 00007f2ad0b24000 CR3: 0000000102a3a006 CR4: 00000000007706e0 [ 4277.407589] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 4277.408780] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 4277.410000] PKRU: 55555554 [ 4277.410645] Call Trace: [ 4277.411234] <TASK> [ 4277.411777] ? die+0x32/0x80 [ 4277.412439] ? do_trap+0xd6/0x100 [ 4277.413150] ? __list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.414158] ? do_error_trap+0x6a/0x90 [ 4277.414948] ? __list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.415915] ? exc_invalid_op+0x4c/0x60 [ 4277.416710] ? __list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.417675] ? asm_exc_invalid_op+0x16/0x20 [ 4277.418482] ? __list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.419466] ? __list_del_entry_valid_or_report+0x7b/0xc0 [ 4277.420410] free_to_partial_list+0x515/0x5e0 [ 4277.421242] ? xfs_iext_remove+0x41a/0xa10 [xfs] [ 4277.422298] xfs_iext_remove+0x41a/0xa10 [xfs] [ 4277.423316] ? xfs_inodegc_worker+0xb4/0x1a0 [xfs] [ 4277.424383] xfs_bmap_del_extent_delay+0x4fe/0x7d0 [xfs] [ 4277.425490] __xfs_bunmapi+0x50d/0x840 [xfs] [ 4277.426445] xfs_itruncate_extents_flags+0x13a/0x490 [xfs] [ 4277.427553] xfs_inactive_truncate+0xa3/0x120 [xfs] [ 4277.428567] xfs_inactive+0x22d/0x290 [xfs] [ 4277.429500] xfs_inodegc_worker+0xb4/0x1a0 [xfs] [ 4277.430479] process_one_work+0x171/0x340 [ 4277.431227] worker_thread+0x277/0x390 [ 4277.431962] ? __pfx_worker_thread+0x10/0x10 [ 4277.432752] kthread+0xf0/0x120 [ 4277.433382] ? __pfx_kthread+0x10/0x10 [ 4277.434134] ret_from_fork+0x2d/0x50 [ 4277.434837] ? __pfx_kthread+0x10/0x10 [ 4277.435566] ret_from_fork_asm+0x1b/0x30 [ 4277.436280] </TASK> Fixes: 643b113849d8 ("slub: enable tracking of full slabs") Suggested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Suggested-by: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: yuan.gao <yuan.gao@ucloud.cn> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09vmstat: call fold_vm_zone_numa_events() before show per zone NUMA eventMengEn Sun1-0/+1
commit 2ea80b039b9af0b71c00378523b71c254fb99c23 upstream. Since 5.14-rc1, NUMA events will only be folded from per-CPU statistics to per zone and global statistics when the user actually needs it. Currently, the kernel has performs the fold operation when reading /proc/vmstat, but does not perform the fold operation in /proc/zoneinfo. This can lead to inaccuracies in the following statistics in zoneinfo: - numa_hit - numa_miss - numa_foreign - numa_interleave - numa_local - numa_other Therefore, before printing per-zone vm_numa_event when reading /proc/zoneinfo, we should also perform the fold operation. Link: https://lkml.kernel.org/r/1730433998-10461-1-git-send-email-mengensun@tencent.com Fixes: f19298b9516c ("mm/vmstat: convert NUMA statistics to basic NUMA counters") Signed-off-by: MengEn Sun <mengensun@tencent.com> Reviewed-by: JinLiang Zheng <alexjlzheng@tencent.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09Rename .data.once to .data..once to fix resetting WARN*_ONCEMasahiro Yamada1-1/+1
[ Upstream commit dbefa1f31a91670c9e7dac9b559625336206466f ] Commit b1fca27d384e ("kernel debug: support resetting WARN*_ONCE") added support for clearing the state of once warnings. However, it is not functional when CONFIG_LD_DEAD_CODE_DATA_ELIMINATION or CONFIG_LTO_CLANG is enabled, because .data.once matches the .data.[0-9a-zA-Z_]* pattern in the DATA_MAIN macro. Commit cb87481ee89d ("kbuild: linker script do not match C names unless LD_DEAD_CODE_DATA_ELIMINATION is configured") was introduced to suppress the issue for the default CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=n case, providing a minimal fix for stable backporting. We were aware this did not address the issue for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y. The plan was to apply correct fixes and then revert cb87481ee89d. [1] Seven years have passed since then, yet the #ifdef workaround remains in place. Meanwhile, commit b1fca27d384e introduced the .data.once section, and commit dc5723b02e52 ("kbuild: add support for Clang LTO") extended the #ifdef. Using a ".." separator in the section name fixes the issue for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION and CONFIG_LTO_CLANG. [1]: https://lore.kernel.org/linux-kbuild/CAK7LNASck6BfdLnESxXUeECYL26yUDm0cwRZuM4gmaWUkxjL5g@mail.gmail.com/ Fixes: b1fca27d384e ("kernel debug: support resetting WARN*_ONCE") Fixes: dc5723b02e52 ("kbuild: add support for Clang LTO") Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-22mm/damon/core: copy nr_accesses when splitting regionSeongJae Park1-0/+1
commit 1f3730fd9e8d4d77fb99c60d0e6ad4b1104e7e04 upstream. Regions split function ('damon_split_region_at()') is called at the beginning of an aggregation interval, and when DAMOS applying the actions and charging quota. Because 'nr_accesses' fields of all regions are reset at the beginning of each aggregation interval, and DAMOS was applying the action at the end of each aggregation interval, there was no need to copy the 'nr_accesses' field to the split-out region. However, commit 42f994b71404 ("mm/damon/core: implement scheme-specific apply interval") made DAMOS applies action on its own timing interval. Hence, 'nr_accesses' should also copied to split-out regions, but the commit didn't. Fix it by copying it. Link: https://lkml.kernel.org/r/20231119171529.66863-1-sj@kernel.org Fixes: 42f994b71404 ("mm/damon/core: implement scheme-specific apply interval") Signed-off-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22mm/damon/core: handle zero schemes apply intervalSeongJae Park1-4/+4
commit 8e7bde615f634a82a44b1f3d293c049fd3ef9ca9 upstream. DAMON's logics to determine if this is the time to apply damos schemes assumes next_apply_sis is always set larger than current passed_sample_intervals. And therefore assume continuously incrementing passed_sample_intervals will make it reaches to the next_apply_sis in future. The logic hence does apply the scheme and update next_apply_sis only if passed_sample_intervals is same to next_apply_sis. If Schemes apply interval is set as zero, however, next_apply_sis is set same to current passed_sample_intervals, respectively. And passed_sample_intervals is incremented before doing the next_apply_sis check. Hence, next_apply_sis becomes larger than next_apply_sis, and the logic says it is not the time to apply schemes and update next_apply_sis. In other words, DAMON stops applying schemes until passed_sample_intervals overflows. Based on the documents and the common sense, a reasonable behavior for such inputs would be applying the schemes for every sampling interval. Handle the case by removing the assumption. Link: https://lkml.kernel.org/r/20241031183757.49610-3-sj@kernel.org Fixes: 42f994b71404 ("mm/damon/core: implement scheme-specific apply interval") Signed-off-by: SeongJae Park <sj@kernel.org> Cc: <stable@vger.kernel.org> [6.7.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22mm/damon/core: check apply interval in damon_do_apply_schemes()SeongJae Park1-4/+11
commit e9e3db69966d5e9e6f7e7d017b407c0025180fe5 upstream. kdamond_apply_schemes() checks apply intervals of schemes and avoid further applying any schemes if no scheme passed its apply interval. However, the following schemes applying function, damon_do_apply_schemes() iterates all schemes without the apply interval check. As a result, the shortest apply interval is applied to all schemes. Fix the problem by checking the apply interval in damon_do_apply_schemes(). Link: https://lkml.kernel.org/r/20240205201306.88562-1-sj@kernel.org Fixes: 42f994b71404 ("mm/damon/core: implement scheme-specific apply interval") Signed-off-by: SeongJae Park <sj@kernel.org> Cc: <stable@vger.kernel.org> [6.7.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22mm: resolve faulty mmap_region() error path behaviourLorenzo Stoakes1-49/+66
[ Upstream commit 5de195060b2e251a835f622759550e6202167641 ] The mmap_region() function is somewhat terrifying, with spaghetti-like control flow and numerous means by which issues can arise and incomplete state, memory leaks and other unpleasantness can occur. A large amount of the complexity arises from trying to handle errors late in the process of mapping a VMA, which forms the basis of recently observed issues with resource leaks and observable inconsistent state. Taking advantage of previous patches in this series we move a number of checks earlier in the code, simplifying things by moving the core of the logic into a static internal function __mmap_region(). Doing this allows us to perform a number of checks up front before we do any real work, and allows us to unwind the writable unmap check unconditionally as required and to perform a CONFIG_DEBUG_VM_MAPLE_TREE validation unconditionally also. We move a number of things here: 1. We preallocate memory for the iterator before we call the file-backed memory hook, allowing us to exit early and avoid having to perform complicated and error-prone close/free logic. We carefully free iterator state on both success and error paths. 2. The enclosing mmap_region() function handles the mapping_map_writable() logic early. Previously the logic had the mapping_map_writable() at the point of mapping a newly allocated file-backed VMA, and a matching mapping_unmap_writable() on success and error paths. We now do this unconditionally if this is a file-backed, shared writable mapping. If a driver changes the flags to eliminate VM_MAYWRITE, however doing so does not invalidate the seal check we just performed, and we in any case always decrement the counter in the wrapper. We perform a debug assert to ensure a driver does not attempt to do the opposite. 3. We also move arch_validate_flags() up into the mmap_region() function. This is only relevant on arm64 and sparc64, and the check is only meaningful for SPARC with ADI enabled. We explicitly add a warning for this arch if a driver invalidates this check, though the code ought eventually to be fixed to eliminate the need for this. With all of these measures in place, we no longer need to explicitly close the VMA on error paths, as we place all checks which might fail prior to a call to any driver mmap hook. This eliminates an entire class of errors, makes the code easier to reason about and more robust. Link: https://lkml.kernel.org/r/6e0becb36d2f5472053ac5d544c0edfe9b899e25.1730224667.git.lorenzo.stoakes@oracle.com Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Tested-by: Mark Brown <broonie@kernel.org> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22mm: refactor arch_calc_vm_flag_bits() and arm64 MTE handlingLorenzo Stoakes3-5/+2
[ Upstream commit 5baf8b037debf4ec60108ccfeccb8636d1dbad81 ] Currently MTE is permitted in two circumstances (desiring to use MTE having been specified by the VM_MTE flag) - where MAP_ANONYMOUS is specified, as checked by arch_calc_vm_flag_bits() and actualised by setting the VM_MTE_ALLOWED flag, or if the file backing the mapping is shmem, in which case we set VM_MTE_ALLOWED in shmem_mmap() when the mmap hook is activated in mmap_region(). The function that checks that, if VM_MTE is set, VM_MTE_ALLOWED is also set is the arm64 implementation of arch_validate_flags(). Unfortunately, we intend to refactor mmap_region() to perform this check earlier, meaning that in the case of a shmem backing we will not have invoked shmem_mmap() yet, causing the mapping to fail spuriously. It is inappropriate to set this architecture-specific flag in general mm code anyway, so a sensible resolution of this issue is to instead move the check somewhere else. We resolve this by setting VM_MTE_ALLOWED much earlier in do_mmap(), via the arch_calc_vm_flag_bits() call. This is an appropriate place to do this as we already check for the MAP_ANONYMOUS case here, and the shmem file case is simply a variant of the same idea - we permit RAM-backed memory. This requires a modification to the arch_calc_vm_flag_bits() signature to pass in a pointer to the struct file associated with the mapping, however this is not too egregious as this is only used by two architectures anyway - arm64 and parisc. So this patch performs this adjustment and removes the unnecessary assignment of VM_MTE_ALLOWED in shmem_mmap(). [akpm@linux-foundation.org: fix whitespace, per Catalin] Link: https://lkml.kernel.org/r/ec251b20ba1964fb64cf1607d2ad80c47f3873df.1730224667.git.lorenzo.stoakes@oracle.com Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andreas Larsson <andreas@gaisler.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Brown <broonie@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22mm: refactor map_deny_write_exec()Lorenzo Stoakes2-2/+2
[ Upstream commit 0fb4a7ad270b3b209e510eb9dc5b07bf02b7edaf ] Refactor the map_deny_write_exec() to not unnecessarily require a VMA parameter but rather to accept VMA flags parameters, which allows us to use this function early in mmap_region() in a subsequent commit. While we're here, we refactor the function to be more readable and add some additional documentation. Link: https://lkml.kernel.org/r/6be8bb59cd7c68006ebb006eb9d8dc27104b1f70.1730224667.git.lorenzo.stoakes@oracle.com Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Jann Horn <jannh@google.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Brown <broonie@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22mm: unconditionally close VMAs on errorLorenzo Stoakes3-8/+22
[ Upstream commit 4080ef1579b2413435413988d14ac8c68e4d42c8 ] Incorrect invocation of VMA callbacks when the VMA is no longer in a consistent state is bug prone and risky to perform. With regards to the important vm_ops->close() callback We have gone to great lengths to try to track whether or not we ought to close VMAs. Rather than doing so and risking making a mistake somewhere, instead unconditionally close and reset vma->vm_ops to an empty dummy operations set with a NULL .close operator. We introduce a new function to do so - vma_close() - and simplify existing vms logic which tracked whether we needed to close or not. This simplifies the logic, avoids incorrect double-calling of the .close() callback and allows us to update error paths to simply call vma_close() unconditionally - making VMA closure idempotent. Link: https://lkml.kernel.org/r/28e89dda96f68c505cb6f8e9fc9b57c3e9f74b42.1730224667.git.lorenzo.stoakes@oracle.com Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Jann Horn <jannh@google.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Brown <broonie@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22mm: avoid unsafe VMA hook invocation when error arises on mmap hookLorenzo Stoakes3-4/+31
[ Upstream commit 3dd6ed34ce1f2356a77fb88edafb5ec96784e3cf ] Patch series "fix error handling in mmap_region() and refactor (hotfixes)", v4. mmap_region() is somewhat terrifying, with spaghetti-like control flow and numerous means by which issues can arise and incomplete state, memory leaks and other unpleasantness can occur. A large amount of the complexity arises from trying to handle errors late in the process of mapping a VMA, which forms the basis of recently observed issues with resource leaks and observable inconsistent state. This series goes to great lengths to simplify how mmap_region() works and to avoid unwinding errors late on in the process of setting up the VMA for the new mapping, and equally avoids such operations occurring while the VMA is in an inconsistent state. The patches in this series comprise the minimal changes required to resolve existing issues in mmap_region() error handling, in order that they can be hotfixed and backported. There is additionally a follow up series which goes further, separated out from the v1 series and sent and updated separately. This patch (of 5): After an attempted mmap() fails, we are no longer in a situation where we can safely interact with VMA hooks. This is currently not enforced, meaning that we need complicated handling to ensure we do not incorrectly call these hooks. We can avoid the whole issue by treating the VMA as suspect the moment that the file->f_ops->mmap() function reports an error by replacing whatever VMA operations were installed with a dummy empty set of VMA operations. We do so through a new helper function internal to mm - mmap_file() - which is both more logically named than the existing call_mmap() function and correctly isolates handling of the vm_op reassignment to mm. All the existing invocations of call_mmap() outside of mm are ultimately nested within the call_mmap() from mm, which we now replace. It is therefore safe to leave call_mmap() in place as a convenience function (and to avoid churn). The invokers are: ovl_file_operations -> mmap -> ovl_mmap() -> backing_file_mmap() coda_file_operations -> mmap -> coda_file_mmap() shm_file_operations -> shm_mmap() shm_file_operations_huge -> shm_mmap() dma_buf_fops -> dma_buf_mmap_internal -> i915_dmabuf_ops -> i915_gem_dmabuf_mmap() None of these callers interact with vm_ops or mappings in a problematic way on error, quickly exiting out. Link: https://lkml.kernel.org/r/cover.1730224667.git.lorenzo.stoakes@oracle.com Link: https://lkml.kernel.org/r/d41fd763496fd0048a962f3fd9407dc72dd4fd86.1730224667.git.lorenzo.stoakes@oracle.com Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Jann Horn <jannh@google.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Brown <broonie@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22mm/damon/core: handle zero {aggregation,ops_update} intervalsSeongJae Park1-3/+3
[ Upstream commit 3488af0970445ff5532c7e8dc5e6456b877aee5e ] Patch series "mm/damon/core: fix handling of zero non-sampling intervals". DAMON's internal intervals accounting logic is not correctly handling non-sampling intervals of zero values for a wrong assumption. This could cause unexpected monitoring behavior, and even result in infinite hang of DAMON sysfs interface user threads in case of zero aggregation interval. Fix those by updating the intervals accounting logic. For details of the root case and solutions, please refer to commit messages of fixes. This patch (of 2): DAMON's logics to determine if this is the time to do aggregation and ops update assumes next_{aggregation,ops_update}_sis are always set larger than current passed_sample_intervals. And therefore it further assumes continuously incrementing passed_sample_intervals every sampling interval will make it reaches to the next_{aggregation,ops_update}_sis in future. The logic therefore make the action and update next_{aggregation,ops_updaste}_sis only if passed_sample_intervals is same to the counts, respectively. If Aggregation interval or Ops update interval are zero, however, next_aggregation_sis or next_ops_update_sis are set same to current passed_sample_intervals, respectively. And passed_sample_intervals is incremented before doing the next_{aggregation,ops_update}_sis check. Hence, passed_sample_intervals becomes larger than next_{aggregation,ops_update}_sis, and the logic says it is not the time to do the action and update next_{aggregation,ops_update}_sis forever, until an overflow happens. In other words, DAMON stops doing aggregations or ops updates effectively forever, and users cannot get monitoring results. Based on the documents and the common sense, a reasonable behavior for such inputs is doing an aggregation and an ops update for every sampling interval. Handle the case by removing the assumption. Note that this could incur particular real issue for DAMON sysfs interface users, in case of zero Aggregation interval. When user starts DAMON with zero Aggregation interval and asks online DAMON parameter tuning via DAMON sysfs interface, the request is handled by the aggregation callback. Until the callback finishes the work, the user who requested the online tuning just waits. Hence, the user will be stuck until the passed_sample_intervals overflows. Link: https://lkml.kernel.org/r/20241031183757.49610-1-sj@kernel.org Link: https://lkml.kernel.org/r/20241031183757.49610-2-sj@kernel.org Fixes: 4472edf63d66 ("mm/damon/core: use number of passed access sampling as a timer") Signed-off-by: SeongJae Park <sj@kernel.org> Cc: <stable@vger.kernel.org> [6.7.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-22mm/damon/core: implement scheme-specific apply intervalSeongJae Park5-9/+72
[ Upstream commit 42f994b71404b17abcd6b170de7a6aa95ffe5d4a ] DAMON-based operation schemes are applied for every aggregation interval. That was mainly because schemes were using nr_accesses, which be complete to be used for every aggregation interval. However, the schemes are now using nr_accesses_bp, which is updated for each sampling interval in a way that reasonable to be used. Therefore, there is no reason to apply schemes for each aggregation interval. The unnecessary alignment with aggregation interval was also making some use cases of DAMOS tricky. Quotas setting under long aggregation interval is one such example. Suppose the aggregation interval is ten seconds, and there is a scheme having CPU quota 100ms per 1s. The scheme will actually uses 100ms per ten seconds, since it cannobe be applied before next aggregation interval. The feature is working as intended, but the results might not that intuitive for some users. This could be fixed by updating the quota to 1s per 10s. But, in the case, the CPU usage of DAMOS could look like spikes, and would actually make a bad effect to other CPU-sensitive workloads. Implement a dedicated timing interval for each DAMON-based operation scheme, namely apply_interval. The interval will be sampling interval aligned, and each scheme will be applied for its apply_interval. The interval is set to 0 by default, and it means the scheme should use the aggregation interval instead. This avoids old users getting any behavioral difference. Link: https://lkml.kernel.org/r/20230916020945.47296-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Cc: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Stable-dep-of: 3488af097044 ("mm/damon/core: handle zero {aggregation,ops_update} intervals") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-22nommu: pass NULL argument to vma_iter_prealloc()Hajime Tazaki1-1/+1
commit 247d720b2c5d22f7281437fd6054a138256986ba upstream. When deleting a vma entry from a maple tree, it has to pass NULL to vma_iter_prealloc() in order to calculate internal state of the tree, but it passed a wrong argument. As a result, nommu kernels crashed upon accessing a vma iterator, such as acct_collect() reading the size of vma entries after do_munmap(). This commit fixes this issue by passing a right argument to the preallocation call. Link: https://lkml.kernel.org/r/20241108222834.3625217-1-thehajime@gmail.com Fixes: b5df09226450 ("mm: set up vma iterator for vma_iter_prealloc() calls") Signed-off-by: Hajime Tazaki <thehajime@gmail.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>