mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/
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25,609 commits
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3dc58c9ce1 |
A couple of late-breaking MM fixes. One against a new-in-this-cycle patch
and the other addresses a locking issue which has been there for 1+ years. -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaYZRhQAKCRDdBJ7gKXxA jhxUAQCPsCziTG1PTXTY12tt4UIY0lppNXP7ltuddHBwry1RRgEAwMbAZq5tvx1S bVnCux9M4uIcBJbWak738Q4wMxcqigg= =8OWj -----END PGP SIGNATURE----- Merge tag 'mm-hotfixes-stable-2026-02-06-12-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull hotfixes from Andrew Morton: "A couple of late-breaking MM fixes. One against a new-in-this-cycle patch and the other addresses a locking issue which has been there for over a year" * tag 'mm-hotfixes-stable-2026-02-06-12-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: mm/memory-failure: reject unsupported non-folio compound page procfs: avoid fetching build ID while holding VMA lock |
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5ca98c22b5 |
slab fix for 6.19-rc8
-----BEGIN PGP SIGNATURE----- iQFPBAABCAA5FiEEe7vIQRWZI0iWSE3xu+CwddJFiJoFAmmFq/4bFIAAAAAABAAO bWFudTIsMi41KzEuMTEsMiwyAAoJELvgsHXSRYiajNsH/Rwx9KuJepaUyCIPHNNK +i7+uAhro222mXNRxz0JtC/uI+Fal/hD9EpnQ9pKfrrTJ7dBoZCP7oMekZXhZkto TzYLb7iSzUIdnvu4e3gcO5H88LCLr0gMLJwY+U1Uk51O5yYsl9LY+B5oC/foi0JV pVAjZofupRLUbu7aPzrz///ia0UYf8TmKZaGrnMa1d/kiK3tWl1G0Tvhph7e4Lgj AF4X3IFf3LsxhKEfkyqyNAXuAFBCB91Hm1wiqf5SDeBGXl5OIylVfj82aV/ZO5TI wjXrUBo/nP5y3xMzPvJfnZT/++aqJFDSC9eIxSelYxpqm5xlNS54Zeo5fFpasHPS Q+c= =MAii -----END PGP SIGNATURE----- Merge tag 'slab-for-6.19-rc8-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab Pull slab fix from Vlastimil Babka: "A stable fix for memory allocation profiling tag not being cleared when aborting an allocation due to memcg charge failure (Hao Ge)" * tag 'slab-for-6.19-rc8-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: mm/slab: Add alloc_tagging_slab_free_hook for memcg_alloc_abort_single |
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e6c53ead2d |
mm/slab: Add alloc_tagging_slab_free_hook for memcg_alloc_abort_single
When CONFIG_MEM_ALLOC_PROFILING_DEBUG is enabled, the following warning
may be noticed:
[ 3959.023862] ------------[ cut here ]------------
[ 3959.023891] alloc_tag was not cleared (got tag for lib/xarray.c:378)
[ 3959.023947] WARNING: ./include/linux/alloc_tag.h:155 at alloc_tag_add+0x128/0x178, CPU#6: mkfs.ntfs/113998
[ 3959.023978] Modules linked in: dns_resolver tun brd overlay exfat btrfs blake2b libblake2b xor xor_neon raid6_pq loop sctp ip6_udp_tunnel udp_tunnel ext4 crc16 mbcache jbd2 rfkill sunrpc vfat fat sg fuse nfnetlink sr_mod virtio_gpu cdrom drm_client_lib virtio_dma_buf drm_shmem_helper drm_kms_helper ghash_ce drm sm4 backlight virtio_net net_failover virtio_scsi failover virtio_console virtio_blk virtio_mmio dm_mirror dm_region_hash dm_log dm_multipath dm_mod i2c_dev aes_neon_bs aes_ce_blk [last unloaded: hwpoison_inject]
[ 3959.024170] CPU: 6 UID: 0 PID: 113998 Comm: mkfs.ntfs Kdump: loaded Tainted: G W 6.19.0-rc7+ #7 PREEMPT(voluntary)
[ 3959.024182] Tainted: [W]=WARN
[ 3959.024186] Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022
[ 3959.024192] pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 3959.024199] pc : alloc_tag_add+0x128/0x178
[ 3959.024207] lr : alloc_tag_add+0x128/0x178
[ 3959.024214] sp : ffff80008b696d60
[ 3959.024219] x29: ffff80008b696d60 x28: 0000000000000000 x27: 0000000000000240
[ 3959.024232] x26: 0000000000000000 x25: 0000000000000240 x24: ffff800085d17860
[ 3959.024245] x23: 0000000000402800 x22: ffff0000c0012dc0 x21: 00000000000002d0
[ 3959.024257] x20: ffff0000e6ef3318 x19: ffff800085ae0410 x18: 0000000000000000
[ 3959.024269] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[ 3959.024281] x14: 0000000000000000 x13: 0000000000000001 x12: ffff600064101293
[ 3959.024292] x11: 1fffe00064101292 x10: ffff600064101292 x9 : dfff800000000000
[ 3959.024305] x8 : 00009fff9befed6e x7 : ffff000320809493 x6 : 0000000000000001
[ 3959.024316] x5 : ffff000320809490 x4 : ffff600064101293 x3 : ffff800080691838
[ 3959.024328] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000d5bcd640
[ 3959.024340] Call trace:
[ 3959.024346] alloc_tag_add+0x128/0x178 (P)
[ 3959.024355] __alloc_tagging_slab_alloc_hook+0x11c/0x1a8
[ 3959.024362] kmem_cache_alloc_lru_noprof+0x1b8/0x5e8
[ 3959.024369] xas_alloc+0x304/0x4f0
[ 3959.024381] xas_create+0x1e0/0x4a0
[ 3959.024388] xas_store+0x68/0xda8
[ 3959.024395] __filemap_add_folio+0x5b0/0xbd8
[ 3959.024409] filemap_add_folio+0x16c/0x7e0
[ 3959.024416] __filemap_get_folio_mpol+0x2dc/0x9e8
[ 3959.024424] iomap_get_folio+0xfc/0x180
[ 3959.024435] __iomap_get_folio+0x2f8/0x4b8
[ 3959.024441] iomap_write_begin+0x198/0xc18
[ 3959.024448] iomap_write_iter+0x2ec/0x8f8
[ 3959.024454] iomap_file_buffered_write+0x19c/0x290
[ 3959.024461] blkdev_write_iter+0x38c/0x978
[ 3959.024470] vfs_write+0x4d4/0x928
[ 3959.024482] ksys_write+0xfc/0x1f8
[ 3959.024489] __arm64_sys_write+0x74/0xb0
[ 3959.024496] invoke_syscall+0xd4/0x258
[ 3959.024507] el0_svc_common.constprop.0+0xb4/0x240
[ 3959.024514] do_el0_svc+0x48/0x68
[ 3959.024520] el0_svc+0x40/0xf8
[ 3959.024526] el0t_64_sync_handler+0xa0/0xe8
[ 3959.024533] el0t_64_sync+0x1ac/0x1b0
[ 3959.024540] ---[ end trace 0000000000000000 ]---
When __memcg_slab_post_alloc_hook() fails, there are two different
free paths depending on whether size == 1 or size != 1. In the
kmem_cache_free_bulk() path, we do call alloc_tagging_slab_free_hook().
However, in memcg_alloc_abort_single() we don't, the above warning will be
triggered on the next allocation.
Therefore, add alloc_tagging_slab_free_hook() to the
memcg_alloc_abort_single() path.
Fixes:
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ae9fd76c11 |
mm/memory-failure: reject unsupported non-folio compound page
When !CONFIG_TRANSPARENT_HUGEPAGE, a non-folio compound page can appear in
a userspace mapping via either vm_insert_*() functions or
vm_operatios_struct->fault(). They are not folios, thus should not be
considered for folio operations like split. To reject these pages, make
sure get_hwpoison_page() is always called as HWPoisonHandlable() will do
the right work.
[Some commit log borrowed from Zi Yan. Thanks.]
Link: https://lkml.kernel.org/r/20260205075328.523211-1-linmiaohe@huawei.com
Fixes:
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b20624608f |
5 hotfixes. 2 are cc:stable, 2 are for MM.
All are singletons - please see the changelogs for details. -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaYPcbwAKCRDdBJ7gKXxA jpM9AQDRiBlZRBdYY8/nS2zMc8hE7s5O3koXu/UMf2O01aJjsgD6AssmcJzkbLir O1mlBSD0wlR3TZLEqSOUYIxgw7evLww= =ZHeq -----END PGP SIGNATURE----- Merge tag 'mm-hotfixes-stable-2026-02-04-15-55' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "Five hotfixes. Two are cc:stable, two are for MM. All are singletons - please see the changelogs for details" * tag 'mm-hotfixes-stable-2026-02-04-15-55' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: Documentation: document liveupdate cmdline parameter mm, shmem: prevent infinite loop on truncate race mailmap: update Alexander Mikhalitsyn's emails liveupdate: luo_file: do not clear serialized_data on unfreeze x86/kfence: fix booting on 32bit non-PAE systems |
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2030dddf95 |
mm, shmem: prevent infinite loop on truncate race
When truncating a large swap entry, shmem_free_swap() returns 0 when the entry's index doesn't match the given index due to lookup alignment. The failure fallback path checks if the entry crosses the end border and aborts when it happens, so truncate won't erase an unexpected entry or range. But one scenario was ignored. When `index` points to the middle of a large swap entry, and the large swap entry doesn't go across the end border, find_get_entries() will return that large swap entry as the first item in the batch with `indices[0]` equal to `index`. The entry's base index will be smaller than `indices[0]`, so shmem_free_swap() will fail and return 0 due to the "base < index" check. The code will then call shmem_confirm_swap(), get the order, check if it crosses the END boundary (which it doesn't), and retry with the same index. The next iteration will find the same entry again at the same index with same indices, leading to an infinite loop. Fix this by retrying with a round-down index, and abort if the index is smaller than the truncate range. Link: https://lkml.kernel.org/r/aXo6ltB5iqAKJzY8@KASONG-MC4 Fixes: |
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bcb6058a4b |
16 hotfixes. 9 are cc:stable, 12 are for MM.
- There's a 3 patch series from Pratyush Yadav which fixes a few things in the new-in-6.19 LUO memfd code. - Plus the usual shower of singletons - please see the changelogs for details. -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaXub9wAKCRDdBJ7gKXxA jjoHAP48ag3lmJnpej977MxrA4VUBhv6ATmbFE2+czCzbRJaigEAiIMWtUlSVYbH WuEYQvcFeSR0hYjs0ClKUiZYOUcj+wI= =lHEL -----END PGP SIGNATURE----- Merge tag 'mm-hotfixes-stable-2026-01-29-09-41' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "16 hotfixes. 9 are cc:stable, 12 are for MM. There's a patch series from Pratyush Yadav which fixes a few things in the new-in-6.19 LUO memfd code. Plus the usual shower of singletons - please see the changelogs for details" * tag 'mm-hotfixes-stable-2026-01-29-09-41' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: vmcoreinfo: make hwerr_data visible for debugging mm/zone_device: reinitialize large zone device private folios mm/mm_init: don't cond_resched() in deferred_init_memmap_chunk() if called from deferred_grow_zone() mm/kfence: randomize the freelist on initialization kho: kho_preserve_vmalloc(): don't return 0 when ENOMEM kho: init alloc tags when restoring pages from reserved memory mm: memfd_luo: restore and free memfd_luo_ser on failure mm: memfd_luo: use memfd_alloc_file() instead of shmem_file_setup() memfd: export alloc_file() flex_proportions: make fprop_new_period() hardirq safe mailmap: add entry for Viacheslav Bocharov mm/memory-failure: teach kill_accessing_process to accept hugetlb tail page pfn mm/memory-failure: fix missing ->mf_stats count in hugetlb poison mm, swap: restore swap_space attr aviod kernel panic mm/kasan: fix KASAN poisoning in vrealloc() mm/shmem, swap: fix race of truncate and swap entry split |
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12b2285bf3 |
mm/zone_device: reinitialize large zone device private folios
Reinitialize metadata for large zone device private folios in
zone_device_page_init prior to creating a higher-order zone device private
folio. This step is necessary when the folio's order changes dynamically
between zone_device_page_init calls to avoid building a corrupt folio. As
part of the metadata reinitialization, the dev_pagemap must be passed in
from the caller because the pgmap stored in the folio page may have been
overwritten with a compound head.
Without this fix, individual pages could have invalid pgmap fields and
flags (with PG_locked being notably problematic) due to prior different
order allocations, which can, and will, result in kernel crashes.
Link: https://lkml.kernel.org/r/20260116111325.1736137-2-francois.dugast@intel.com
Fixes:
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cbbbf7795f |
mm/mm_init: don't cond_resched() in deferred_init_memmap_chunk() if called from deferred_grow_zone()
Commit |
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870ff19251 |
mm/kfence: randomize the freelist on initialization
Randomize the KFENCE freelist during pool initialization to make
allocation patterns less predictable. This is achieved by shuffling the
order in which metadata objects are added to the freelist using
get_random_u32_below().
Additionally, ensure the error path correctly calculates the address range
to be reset if initialization fails, as the address increment logic has
been moved to a separate loop.
Link: https://lkml.kernel.org/r/20260120161510.3289089-1-pimyn@google.com
Fixes:
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c657c5dc13 |
mm: memfd_luo: restore and free memfd_luo_ser on failure
memfd_luo_ser has the serialization metadata. It is of no use once
restoration fails. Free it on failure.
Link: https://lkml.kernel.org/r/20260122151842.4069702-4-pratyush@kernel.org
Fixes:
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02e117b8ca |
mm: memfd_luo: use memfd_alloc_file() instead of shmem_file_setup()
When restoring a memfd, the file is created using shmem_file_setup().
While memfd creation also calls this function to get the file, it also
does other things:
1. The O_LARGEFILE flag is set on the file. If this is not done,
writes on the memfd exceeding 2 GiB fail.
2. FMODE_LSEEK, FMODE_PREAD, and FMODE_PWRITE are set on the file.
This makes sure the file is seekable and can be used with pread() and
pwrite().
3. Initializes the security field for the inode and makes sure that
inode creation is permitted by the security module.
Currently, none of those things are done. This means writes above 2 GiB
fail, pread(), and pwrite() fail, and so on. lseek() happens to work
because file_init_path() sets it because shmem defines fop->llseek.
Fix this by using memfd_alloc_file() to get the file to make sure the
initialization sequence for normal and preserved memfd is the same.
Link: https://lkml.kernel.org/r/20260122151842.4069702-3-pratyush@kernel.org
Fixes:
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71e2b5eadb |
memfd: export alloc_file()
Patch series "mm: memfd_luo hotfixes". This series contains a couple of fixes for memfd preservation using LUO. This patch (of 3): The Live Update Orchestrator's (LUO) memfd preservation works by preserving all the folios of a memfd, re-creating an empty memfd on the next boot, and then inserting back the preserved folios. Currently it creates the file by directly calling shmem_file_setup(). This leaves out other work done by alloc_file() like setting up the file mode, flags, or calling the security hooks. Export alloc_file() to let memfd_luo use it. Rename it to memfd_alloc_file() since it is no longer private and thus needs a subsystem prefix. Link: https://lkml.kernel.org/r/20260122151842.4069702-1-pratyush@kernel.org Link: https://lkml.kernel.org/r/20260122151842.4069702-2-pratyush@kernel.org Signed-off-by: Pratyush Yadav (Google) <pratyush@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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057a6f2632 |
mm/memory-failure: teach kill_accessing_process to accept hugetlb tail page pfn
When a hugetlb folio is being poisoned again, try_memory_failure_hugetlb() passed head pfn to kill_accessing_process(), that is not right. The precise pfn of the poisoned page should be used in order to determine the precise vaddr as the SIGBUS payload. This issue has already been taken care of in the normal path, that is, hwpoison_user_mappings(), see [1][2]. Further more, for [3] to work correctly in the hugetlb repoisoning case, it's essential to inform VM the precise poisoned page, not the head page. [1] https://lkml.kernel.org/r/20231218135837.3310403-1-willy@infradead.org [2] https://lkml.kernel.org/r/20250224211445.2663312-1-jane.chu@oracle.com [3] https://lore.kernel.org/lkml/20251116013223.1557158-1-jiaqiyan@google.com/ Link: https://lkml.kernel.org/r/20260120232234.3462258-2-jane.chu@oracle.com Signed-off-by: Jane Chu <jane.chu@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Acked-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Chris Mason <clm@meta.com> Cc: David Hildenbrand <david@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Jiaqi Yan <jiaqiyan@google.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Suren Baghdasaryan <surenb@google.com> Cc: William Roche <william.roche@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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a148a20401 |
mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
When a newly poisoned subpage ends up in an already poisoned hugetlb
folio, 'num_poisoned_pages' is incremented, but the per node ->mf_stats is
not. Fix the inconsistency by designating action_result() to update them
both.
While at it, define __get_huge_page_for_hwpoison() return values in terms
of symbol names for better readibility. Also rename
folio_set_hugetlb_hwpoison() to hugetlb_update_hwpoison() since the
function does more than the conventional bit setting and the fact three
possible return values are expected.
Link: https://lkml.kernel.org/r/20260120232234.3462258-1-jane.chu@oracle.com
Fixes:
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a0f3c0845a |
mm, swap: restore swap_space attr aviod kernel panic
commit |
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9b47d4eea3 |
mm/kasan: fix KASAN poisoning in vrealloc()
A KASAN warning can be triggered when vrealloc() changes the requested
size to a value that is not aligned to KASAN_GRANULE_SIZE.
------------[ cut here ]------------
WARNING: CPU: 2 PID: 1 at mm/kasan/shadow.c:174 kasan_unpoison+0x40/0x48
...
pc : kasan_unpoison+0x40/0x48
lr : __kasan_unpoison_vmalloc+0x40/0x68
Call trace:
kasan_unpoison+0x40/0x48 (P)
vrealloc_node_align_noprof+0x200/0x320
bpf_patch_insn_data+0x90/0x2f0
convert_ctx_accesses+0x8c0/0x1158
bpf_check+0x1488/0x1900
bpf_prog_load+0xd20/0x1258
__sys_bpf+0x96c/0xdf0
__arm64_sys_bpf+0x50/0xa0
invoke_syscall+0x90/0x160
Introduce a dedicated kasan_vrealloc() helper that centralizes KASAN
handling for vmalloc reallocations. The helper accounts for KASAN granule
alignment when growing or shrinking an allocation and ensures that partial
granules are handled correctly.
Use this helper from vrealloc_node_align_noprof() to fix poisoning logic.
[ryabinin.a.a@gmail.com: move kasan_enabled() check, fix build]
Link: https://lkml.kernel.org/r/20260119144509.32767-1-ryabinin.a.a@gmail.com
Link: https://lkml.kernel.org/r/20260113191516.31015-1-ryabinin.a.a@gmail.com
Fixes:
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8a1968bd99 |
mm/shmem, swap: fix race of truncate and swap entry split
The helper for shmem swap freeing is not handling the order of swap
entries correctly. It uses xa_cmpxchg_irq to erase the swap entry, but it
gets the entry order before that using xa_get_order without lock
protection, and it may get an outdated order value if the entry is split
or changed in other ways after the xa_get_order and before the
xa_cmpxchg_irq.
And besides, the order could grow and be larger than expected, and cause
truncation to erase data beyond the end border. For example, if the
target entry and following entries are swapped in or freed, then a large
folio was added in place and swapped out, using the same entry, the
xa_cmpxchg_irq will still succeed, it's very unlikely to happen though.
To fix that, open code the Xarray cmpxchg and put the order retrieval and
value checking in the same critical section. Also, ensure the order won't
exceed the end border, skip it if the entry goes across the border.
Skipping large swap entries crosses the end border is safe here. Shmem
truncate iterates the range twice, in the first iteration,
find_lock_entries already filtered such entries, and shmem will swapin the
entries that cross the end border and partially truncate the folio (split
the folio or at least zero part of it). So in the second loop here, if we
see a swap entry that crosses the end order, it must at least have its
content erased already.
I observed random swapoff hangs and kernel panics when stress testing
ZSWAP with shmem. After applying this patch, all problems are gone.
Link: https://lkml.kernel.org/r/20260120-shmem-swap-fix-v3-1-3d33ebfbc057@tencent.com
Fixes:
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119d1cbc6e |
slab fix for 6.19-rc7
-----BEGIN PGP SIGNATURE----- iQFPBAABCAA5FiEEe7vIQRWZI0iWSE3xu+CwddJFiJoFAmlwq+MbFIAAAAAABAAO bWFudTIsMi41KzEuMTEsMiwyAAoJELvgsHXSRYiagDcH+gIapvbu8Y7gi3XT1rcj YBalI8n3MH5ZpZP/a44Xs7rICb2Kmk2Kre6x22vI62aGmMHc3vJWlXslWSXrCLZj d5K3ILSkV70GVgtVYEJv3iFde/OCGS6ksakzjZMs4vSMJhsAWNrRTZiVd6p9mNSw yy+PM34xt6hTL7nYSLMTmVoS7zHiZDIusqElto721ZCiTG9Nb7FdojvneKKYvCt8 5WW7h4FoKEFBv5Q8oCWuevSGEclxOHL3H+3dlDy2/OE2SaqAWB5AcwOvoc6Gbzgk bzxF0vLjQX1YP60J/GNOOueEHUhhiqNQwnkhUvqq3rg08qNVQ2jRz5J4luxtrMB6 tqU= =7faF -----END PGP SIGNATURE----- Merge tag 'slab-for-6.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab Pull slab fix from Vlastimil Babka: - A stable fix for kmalloc_nolock() in non-preemptible contexts on PREEMPT_RT (Swaraj Gaikwad) * tag 'slab-for-6.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: slab: fix kmalloc_nolock() context check for PREEMPT_RT |
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99a3e3a1cf |
slab: fix kmalloc_nolock() context check for PREEMPT_RT
On PREEMPT_RT kernels, local_lock becomes a sleeping lock. The current
check in kmalloc_nolock() only verifies we're not in NMI or hard IRQ
context, but misses the case where preemption is disabled.
When a BPF program runs from a tracepoint with preemption disabled
(preempt_count > 0), kmalloc_nolock() proceeds to call
local_lock_irqsave() which attempts to acquire a sleeping lock,
triggering:
BUG: sleeping function called from invalid context
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 6128
preempt_count: 2, expected: 0
Fix this by checking !preemptible() on PREEMPT_RT, which directly
expresses the constraint that we cannot take a sleeping lock when
preemption is disabled. This encompasses the previous checks for NMI
and hard IRQ contexts while also catching cases where preemption is
disabled.
Fixes:
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c25f2fb1f4 |
17 hotfixes. 12 are cc:stable, 16 are for MM.
- A 4 patch series from David Hildenbrand which fixes a few things realted to hugetlb PMD sharing - The remainder are singletons, please see their changelogs for details. -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaW/vEQAKCRDdBJ7gKXxA jtMcAQCK1tKnINRmVjY3UJCqZMAaXvOdOoUIgHDaTXD/DWKm9AD9HRwWzYB4+TNr k/Te8F33d418LcMBTW9CLhrplQpaIAI= =+d1A -----END PGP SIGNATURE----- Merge tag 'mm-hotfixes-stable-2026-01-20-13-09' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: - A patch series from David Hildenbrand which fixes a few things related to hugetlb PMD sharing - The remainder are singletons, please see their changelogs for details * tag 'mm-hotfixes-stable-2026-01-20-13-09' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: mm: restore per-memcg proactive reclaim with !CONFIG_NUMA mm/kfence: fix potential deadlock in reboot notifier Docs/mm/allocation-profiling: describe sysctrl limitations in debug mode mm: do not copy page tables unnecessarily for VM_UFFD_WP mm/hugetlb: fix excessive IPI broadcasts when unsharing PMD tables using mmu_gather mm/rmap: fix two comments related to huge_pmd_unshare() mm/hugetlb: fix two comments related to huge_pmd_unshare() mm/hugetlb: fix hugetlb_pmd_shared() mm: remove unnecessary and incorrect mmap lock assert x86/kfence: avoid writing L1TF-vulnerable PTEs mm/vma: do not leak memory when .mmap_prepare swaps the file migrate: correct lock ordering for hugetlb file folios panic: only warn about deprecated panic_print on write access fs/writeback: skip AS_NO_DATA_INTEGRITY mappings in wait_sb_inodes() mm: take into account mm_cid size for mm_struct static definitions mm: rename cpu_bitmap field to flexible_array mm: add missing static initializer for init_mm::mm_cid.lock |
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c03e9c42ae |
dma-mapping fixes for Linux 6.19
- minor fixes for the corner cases of the SWIOTLB pool management (Robin Murphy) -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQSrngzkoBtlA8uaaJ+Jp1EFxbsSRAUCaW+NbgAKCRCJp1EFxbsS RKU3AQCIpNwIYN6evmnTXO/Y+AFRjsrb1pE1cUyHn5QTY4/o4wEA6BiSgMCrZEbv HTEs1ZSHgLOwBwZre1Z11icGg3BkRgY= =6fBC -----END PGP SIGNATURE----- Merge tag 'dma-mapping-6.19-2026-01-20' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux Pull dma-mapping fixes from Marek Szyprowski: - minor fixes for the corner cases of the SWIOTLB pool management (Robin Murphy) * tag 'dma-mapping-6.19-2026-01-20' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: dma/pool: Avoid allocating redundant pools mm_zone: Generalise has_managed_dma() dma/pool: Improve pool lookup |
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16aca2c98a |
mm: restore per-memcg proactive reclaim with !CONFIG_NUMA
Commit |
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9bc9ccbf4c |
mm/kfence: fix potential deadlock in reboot notifier
The reboot notifier callback can deadlock when calling
cancel_delayed_work_sync() if toggle_allocation_gate() is blocked in
wait_event_idle() waiting for allocations, that might not happen on
shutdown path.
The issue is that cancel_delayed_work_sync() waits for the work to
complete, but the work is waiting for kfence_allocation_gate > 0 which
requires allocations to happen (each allocation is increased by 1) -
allocations that may have stopped during shutdown.
Fix this by:
1. Using cancel_delayed_work() (non-sync) to avoid blocking. Now the
callback succeeds and return.
2. Adding wake_up() to unblock any waiting toggle_allocation_gate()
3. Adding !kfence_enabled to the wait condition so the wake succeeds
The static_branch_disable() IPI will still execute after the wake, but at
this early point in shutdown (reboot notifier runs with INT_MAX priority),
the system is still functional and CPUs can respond to IPIs.
Link: https://lkml.kernel.org/r/20260116-kfence_fix-v1-1-4165a055933f@debian.org
Fixes:
|
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35e2470326 |
mm: do not copy page tables unnecessarily for VM_UFFD_WP
Commit |
||
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8ce720d5bd |
mm/hugetlb: fix excessive IPI broadcasts when unsharing PMD tables using mmu_gather
As reported, ever since commit |
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a8682d500f |
mm/rmap: fix two comments related to huge_pmd_unshare()
PMD page table unsharing no longer touches the refcount of a PMD page
table. Also, it is not about dropping the refcount of a "PMD page" but
the "PMD page table".
Let's just simplify by saying that the PMD page table was unmapped,
consequently also unmapping the folio that was mapped into this page.
This code should be deduplicated in the future.
Link: https://lkml.kernel.org/r/20251223214037.580860-4-david@kernel.org
Fixes:
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3937027cae |
mm/hugetlb: fix two comments related to huge_pmd_unshare()
Ever since we stopped using the page count to detect shared PMD page tables, these comments are outdated. The only reason we have to flush the TLB early is because once we drop the i_mmap_rwsem, the previously shared page table could get freed (to then get reallocated and used for other purpose). So we really have to flush the TLB before that could happen. So let's simplify the comments a bit. The "If we unshared PMDs, the TLB flush was not recorded in mmu_gather." part introduced as in commit |
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90888b4ae1 |
mm: remove unnecessary and incorrect mmap lock assert
This check was introduced by commit |
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605f6586ec |
mm/vma: do not leak memory when .mmap_prepare swaps the file
The current implementation of mmap() is set up such that a struct file object is obtained for the input fd in ksys_mmap_pgoff() via fget(), and its reference count decremented at the end of the function via. fput(). If a merge can be achieved, we are fine to simply decrement the refcount on the file. Otherwise, in __mmap_new_file_vma(), we increment the reference count on the file via get_file() such that the fput() in ksys_mmap_pgoff() does not free the now-referenced file object. The introduction of the f_op->mmap_prepare hook changes things, as it becomes possible for a driver to replace the file object right at the beginning of the mmap operation. The current implementation is buggy if this happens because it unconditionally calls get_file() on the mapping's file whether or not it was replaced (and thus whether or not its reference count will be decremented at the end of ksys_mmap_pgoff()). This results in a memory leak, and was exposed in commit |
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b7880cb166 |
migrate: correct lock ordering for hugetlb file folios
Syzbot has found a deadlock (analyzed by Lance Yang):
1) Task (5749): Holds folio_lock, then tries to acquire i_mmap_rwsem(read lock).
2) Task (5754): Holds i_mmap_rwsem(write lock), then tries to acquire
folio_lock.
migrate_pages()
-> migrate_hugetlbs()
-> unmap_and_move_huge_page() <- Takes folio_lock!
-> remove_migration_ptes()
-> __rmap_walk_file()
-> i_mmap_lock_read() <- Waits for i_mmap_rwsem(read lock)!
hugetlbfs_fallocate()
-> hugetlbfs_punch_hole() <- Takes i_mmap_rwsem(write lock)!
-> hugetlbfs_zero_partial_page()
-> filemap_lock_hugetlb_folio()
-> filemap_lock_folio()
-> __filemap_get_folio <- Waits for folio_lock!
The migration path is the one taking locks in the wrong order according to
the documentation at the top of mm/rmap.c. So expand the scope of the
existing i_mmap_lock to cover the calls to remove_migration_ptes() too.
This is (mostly) how it used to be after commit
|
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6ac433f8b2 |
mm: rename cpu_bitmap field to flexible_array
The cpu_bitmap flexible array now contains more than just the cpu_bitmap.
In preparation for changing the static mm_struct definitions to cover for
the additional space required, change the cpu_bitmap type from "unsigned
long" to "char", require an unsigned long alignment of the flexible array,
and rename the field from "cpu_bitmap" to "flexible_array".
Introduce the MM_STRUCT_FLEXIBLE_ARRAY_INIT macro to statically initialize
the flexible array. This covers the init_mm and efi_mm static
definitions.
This is a preparation step for fixing the missing mm_cid size for static
mm_struct definitions.
Link: https://lkml.kernel.org/r/20251224173358.647691-3-mathieu.desnoyers@efficios.com
Fixes:
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12a6ddfc76 |
mm: add missing static initializer for init_mm::mm_cid.lock
Initialize the mm_cid.lock struct member of init_mm.
Link: https://lkml.kernel.org/r/20251224173358.647691-2-mathieu.desnoyers@efficios.com
Fixes:
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6782a30d20 |
cxl fixes for v6.19-rc6
- Recognize all ZONE_DEVICE users as physaddr consumers - Fix format string for extended_linear_cache_size_show() - Fix target list setup for multiple decoders sharing the same downstream port - Restore HBIW check before derefernce platform data - Fix potential infinite loop in __cxl_dpa_reserve() - Check for invalid addresses returned from translation functions on error. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEE5DAy15EJMCV1R6v9YGjFFmlTOEoFAmlqdOUACgkQYGjFFmlT OEp6bA/8C5uSMf4BMN+gJMerX1wTcVfmDy3nYyk80ZM4Gw2QqxrhtRzG3bfeYaXm IioxYVMWscqasN16xuX7uje2sSDvoPTZYJ2tfnzKfAbyReknlolXvjWJtgoSuVKj IGZDGLjuW0CcTpFW8NgNGiiSExnv6Iap7CnzRTXj72ZQkGcb8Goh4JL/CmAWrF8m HQDbFZWQHI60rOLgxTXgWzlNKej4/tZfCTRKV1KIhqRv+MCurzNPb62H+giCwGDh M+apYESCW3xCk2B7RbGmc6U+rcSmCNc3O31JL3Yt9TKPp4V5N0kaH8dd1196GnQX HOJFlDjV5J/HTJjk4vondyAcIcUaSw3T7IJLtBRbXOBrs1zQ76adV96UNSwSEQC4 KaRjRf0uCsdDvwBw44VbxnWJiH6Y6jrMhKGPyCrXxFikX2EIR5I1l7+ytKDTNC/+ wdAf3+ch3qc6PfTBtooAWzji9e8JFfWpby87UHkWSz0eeKedJQnMbKtbloc6tHLc fO/jiUbhay5QGfnvdPwL31zTGqvZB9eGUR2oBSasRJ7taWvURN2ibAzhAnTY8UTN EQrTZ7isXPfxHwEkaGtpFNWts0iX8kJYzl/wjZjWtukltT4NmMy7NfMlkecXWQ5N iueUMr6tHKYeDpmmFbdC+Y83LFSWv3i9TiINF1vMWuRj8MryRVU= =pIv9 -----END PGP SIGNATURE----- Merge tag 'cxl-fixes-6.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl Pull Compute Express Link (CXL) fixes from Dave Jiang: - Recognize all ZONE_DEVICE users as physaddr consumers - Fix format string for extended_linear_cache_size_show() - Fix target list setup for multiple decoders sharing the same downstream port - Restore HBIW check before derefernce platform data - Fix potential infinite loop in __cxl_dpa_reserve() - Check for invalid addresses returned from translation functions on error * tag 'cxl-fixes-6.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: cxl: Check for invalid addresses returned from translation functions on errors cxl/hdm: Fix potential infinite loop in __cxl_dpa_reserve() cxl/acpi: Restore HBIW check before dereferencing platform_data cxl/port: Fix target list setup for multiple decoders sharing the same dport cxl/region: fix format string for resource_size_t x86/kaslr: Recognize all ZONE_DEVICE users as physaddr consumers |
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f46c26f1bc |
mm: numa,memblock: include <asm/numa.h> for 'numa_nodes_parsed'
The 'numa_nodes_parsed' is defined in <asm/numa.h> but this file
is not included in mm/numa_memblks.c (build x86_64) so add this
to the incldues to fix the following sparse warning:
mm/numa_memblks.c:13:12: warning: symbol 'numa_nodes_parsed' was not declared. Should it be static?
Link: https://lkml.kernel.org/r/20260108101539.229192-1-ben.dooks@codethink.co.uk
Fixes:
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038a102535 |
mm/page_alloc: prevent pcp corruption with SMP=n
The kernel test robot has reported: BUG: spinlock trylock failure on UP on CPU#0, kcompactd0/28 lock: 0xffff888807e35ef0, .magic: dead4ead, .owner: kcompactd0/28, .owner_cpu: 0 CPU: 0 UID: 0 PID: 28 Comm: kcompactd0 Not tainted 6.18.0-rc5-00127-ga06157804399 #1 PREEMPT 8cc09ef94dcec767faa911515ce9e609c45db470 Call Trace: <IRQ> __dump_stack (lib/dump_stack.c:95) dump_stack_lvl (lib/dump_stack.c:123) dump_stack (lib/dump_stack.c:130) spin_dump (kernel/locking/spinlock_debug.c:71) do_raw_spin_trylock (kernel/locking/spinlock_debug.c:?) _raw_spin_trylock (include/linux/spinlock_api_smp.h:89 kernel/locking/spinlock.c:138) __free_frozen_pages (mm/page_alloc.c:2973) ___free_pages (mm/page_alloc.c:5295) __free_pages (mm/page_alloc.c:5334) tlb_remove_table_rcu (include/linux/mm.h:? include/linux/mm.h:3122 include/asm-generic/tlb.h:220 mm/mmu_gather.c:227 mm/mmu_gather.c:290) ? __cfi_tlb_remove_table_rcu (mm/mmu_gather.c:289) ? rcu_core (kernel/rcu/tree.c:?) rcu_core (include/linux/rcupdate.h:341 kernel/rcu/tree.c:2607 kernel/rcu/tree.c:2861) rcu_core_si (kernel/rcu/tree.c:2879) handle_softirqs (arch/x86/include/asm/jump_label.h:36 include/trace/events/irq.h:142 kernel/softirq.c:623) __irq_exit_rcu (arch/x86/include/asm/jump_label.h:36 kernel/softirq.c:725) irq_exit_rcu (kernel/softirq.c:741) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1052) </IRQ> <TASK> RIP: 0010:_raw_spin_unlock_irqrestore (arch/x86/include/asm/preempt.h:95 include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) free_pcppages_bulk (mm/page_alloc.c:1494) drain_pages_zone (include/linux/spinlock.h:391 mm/page_alloc.c:2632) __drain_all_pages (mm/page_alloc.c:2731) drain_all_pages (mm/page_alloc.c:2747) kcompactd (mm/compaction.c:3115) kthread (kernel/kthread.c:465) ? __cfi_kcompactd (mm/compaction.c:3166) ? __cfi_kthread (kernel/kthread.c:412) ret_from_fork (arch/x86/kernel/process.c:164) ? __cfi_kthread (kernel/kthread.c:412) ret_from_fork_asm (arch/x86/entry/entry_64.S:255) </TASK> Matthew has analyzed the report and identified that in drain_page_zone() we are in a section protected by spin_lock(&pcp->lock) and then get an interrupt that attempts spin_trylock() on the same lock. The code is designed to work this way without disabling IRQs and occasionally fail the trylock with a fallback. However, the SMP=n spinlock implementation assumes spin_trylock() will always succeed, and thus it's normally a no-op. Here the enabled lock debugging catches the problem, but otherwise it could cause a corruption of the pcp structure. The problem has been introduced by commit |
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4795d205d7 |
mm: kmsan: fix poisoning of high-order non-compound pages
kmsan_free_page() is called by the page allocator's free_pages_prepare()
during page freeing. Its job is to poison all the memory covered by the
page. It can be called with an order-0 page, a compound high-order page
or a non-compound high-order page. But page_size() only works for order-0
and compound pages. For a non-compound high-order page it will
incorrectly return PAGE_SIZE.
The implication is that the tail pages of a high-order non-compound page
do not get poisoned at free, so any invalid access while they are free
could go unnoticed. It looks like the pages will be poisoned again at
allocation time, so that would bookend the window.
Fix this by using the order parameter to calculate the size.
Link: https://lkml.kernel.org/r/20260104134348.3544298-1-ryan.roberts@arm.com
Fixes:
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3b617fd3d3 |
mm/vma: enforce VMA fork limit on unfaulted,faulted mremap merge too
The is_mergeable_anon_vma() function uses vmg->middle as the source VMA. However when merging a new VMA, this field is NULL. In all cases except mremap(), the new VMA will either be newly established and thus lack an anon_vma, or will be an expansion of an existing VMA thus we do not care about whether VMA is CoW'd or not. In the case of an mremap(), we can end up in a situation where we can accidentally allow an unfaulted/faulted merge with a VMA that has been forked, violating the general rule that we do not permit this for reasons of anon_vma lock scalability. Now we have the ability to be aware of the fact we are copying a VMA and also know which VMA that is, we can explicitly check for this, so do so. This is pertinent since commit |
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61f67c230a |
mm/vma: fix anon_vma UAF on mremap() faulted, unfaulted merge
Patch series "mm/vma: fix anon_vma UAF on mremap() faulted, unfaulted merge", v2. Commit |
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590b13669b |
mm/zswap: fix error pointer free in zswap_cpu_comp_prepare()
crypto_alloc_acomp_node() may return ERR_PTR(), but the fail path checks
only for NULL and can pass an error pointer to crypto_free_acomp(). Use
IS_ERR_OR_NULL() to only free valid acomp instances.
Link: https://lkml.kernel.org/r/20251231074638.2564302-1-pbutsykin@cloudlinux.com
Fixes:
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392b3d9d59 |
mm/damon/sysfs-scheme: cleanup access_pattern subdirs on scheme dir setup failure
When a DAMOS-scheme DAMON sysfs directory setup fails after setup of
access_pattern/ directory, subdirectories of access_pattern/ directory are
not cleaned up. As a result, DAMON sysfs interface is nearly broken until
the system reboots, and the memory for the unremoved directory is leaked.
Cleanup the directories under such failures.
Link: https://lkml.kernel.org/r/20251225023043.18579-5-sj@kernel.org
Fixes:
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dc7e1d75fd |
mm/damon/sysfs-scheme: cleanup quotas subdirs on scheme dir setup failure
When a DAMOS-scheme DAMON sysfs directory setup fails after setup of
quotas/ directory, subdirectories of quotas/ directory are not cleaned up.
As a result, DAMON sysfs interface is nearly broken until the system
reboots, and the memory for the unremoved directory is leaked.
Cleanup the directories under such failures.
Link: https://lkml.kernel.org/r/20251225023043.18579-4-sj@kernel.org
Fixes:
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9814cc832b |
mm/damon/sysfs: cleanup attrs subdirs on context dir setup failure
When a context DAMON sysfs directory setup is failed after setup of attrs/
directory, subdirectories of attrs/ directory are not cleaned up. As a
result, DAMON sysfs interface is nearly broken until the system reboots,
and the memory for the unremoved directory is leaked.
Cleanup the directories under such failures.
Link: https://lkml.kernel.org/r/20251225023043.18579-3-sj@kernel.org
Fixes:
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a24ca8ebb0 |
mm/damon/sysfs: cleanup intervals subdirs on attrs dir setup failure
Patch series "mm/damon/sysfs: free setup failures generated zombie sub-sub
dirs".
Some DAMON sysfs directory setup functions generates its sub and sub-sub
directories. For example, 'monitoring_attrs/' directory setup creates
'intervals/' and 'intervals/intervals_goal/' directories under
'monitoring_attrs/' directory. When such sub-sub directories are
successfully made but followup setup is failed, the setup function should
recursively clean up the subdirectories.
However, such setup functions are only dereferencing sub directory
reference counters. As a result, under certain setup failures, the
sub-sub directories keep having non-zero reference counters. It means the
directories cannot be removed like zombies, and the memory for the
directories cannot be freed.
The user impact of this issue is limited due to the following reasons.
When the issue happens, the zombie directories are still taking the path.
Hence attempts to generate the directories again will fail, without
additional memory leak. This means the upper bound memory leak is
limited. Nonetheless this also implies controlling DAMON with a feature
that requires the setup-failed sysfs files will be impossible until the
system reboots.
Also, the setup operations are quite simple. The certain failures would
hence only rarely happen, and are difficult to artificially trigger.
This patch (of 4):
When attrs/ DAMON sysfs directory setup is failed after setup of
intervals/ directory, intervals/intervals_goal/ directory is not cleaned
up. As a result, DAMON sysfs interface is nearly broken until the system
reboots, and the memory for the unremoved directory is leaked.
Cleanup the directory under such failures.
Link: https://lkml.kernel.org/r/20251225023043.18579-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20251225023043.18579-2-sj@kernel.org
Fixes:
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f9132fbc2e |
mm/damon/core: remove call_control in inactive contexts
If damon_call() is executed against a DAMON context that is not running,
the function returns error while keeping the damon_call_control object
linked to the context's call_controls list. Let's suppose the object is
deallocated after the damon_call(), and yet another damon_call() is
executed against the same context. The function tries to add the new
damon_call_control object to the call_controls list, which still has the
pointer to the previous damon_call_control object, which is deallocated.
As a result, use-after-free happens.
This can actually be triggered using the DAMON sysfs interface. It is not
easily exploitable since it requires the sysfs write permission and making
a definitely weird file writes, though. Please refer to the report for
more details about the issue reproduction steps.
Fix the issue by making two changes. Firstly, move the final
kdamond_call() for cancelling all existing damon_call() requests from
terminating DAMON context to be done before the ctx->kdamond reset. This
makes any code that sees NULL ctx->kdamond can safely assume the context
may not access damon_call() requests anymore. Secondly, let damon_call()
to cleanup the damon_call_control objects that were added to the
already-terminated DAMON context, before returning the error.
Link: https://lkml.kernel.org/r/20251231012315.75835-1-sj@kernel.org
Fixes:
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b020191692 |
mm/hugetlb: ignore hugepage kernel args if hugepages are unsupported
Skip processing hugepage kernel arguments (hugepagesz, hugepages, and
default_hugepagesz) when hugepages are not supported by the architecture.
Some architectures may need to disable hugepages based on conditions
discovered during kernel boot. The hugepages_supported() helper allows
architecture code to advertise whether hugepages are supported.
Currently, normal hugepage allocation is guarded by hugepages_supported(),
but gigantic hugepages are allocated regardless of this check. This
causes problems on powerpc for fadump (firmware- assisted dump).
In the fadump (firmware-assisted dump) scenario, a production kernel crash
causes the system to boot into a special kernel whose sole purpose is to
collect the memory dump and reboot. Features such as hugepages are not
required in this environment and should be disabled.
For example, when the fadump kernel boots with the following kernel
arguments:
default_hugepagesz=1GB hugepagesz=1GB hugepages=200
Before this patch, the kernel prints the following logs:
HugeTLB: allocating 200 of page size 1.00 GiB failed. Only allocated 58 hugepages.
HugeTLB support is disabled!
HugeTLB: huge pages not supported, ignoring associated command-line parameters
hugetlbfs: disabling because there are no supported hugepage sizes
Even though the logs state that HugeTLB support is disabled, gigantic
hugepages are still allocated. This causes the fadump kernel to run out
of memory during boot.
After this patch is applied, the kernel prints the following logs for
the same command line:
HugeTLB: hugepages unsupported, ignoring default_hugepagesz=1GB cmdline
HugeTLB: hugepages unsupported, ignoring hugepagesz=1GB cmdline
HugeTLB: hugepages unsupported, ignoring hugepages=200 cmdline
HugeTLB support is disabled!
hugetlbfs: disabling because there are no supported hugepage sizes
To fix the issue, gigantic hugepage allocation should be guarded by
hugepages_supported().
Previously, two approaches were proposed to bring gigantic hugepage
allocation under hugepages_supported():
[1] Check hugepages_supported() in the generic code before allocating
gigantic hugepages
[2] Make arch_hugetlb_valid_size() return false for all hugetlb sizes
Approach [2] has two minor issues:
1. It prints misleading logs about invalid hugepage sizes
2. The kernel still processes hugepage kernel arguments unnecessarily
To control gigantic hugepage allocation, skip processing hugepage kernel
arguments (default_hugepagesz, hugepagesz and hugepages) when
hugepages_supported() returns false.
Note for backporting: This fix is a partial reversion of the commit
mentioned in the Fixes tag and is only valid once the change referenced by
the Depends-on tag is present. When backporting this patch, the commit
mentioned in the Depends-on tag must be included first.
Link: https://lore.kernel.org/all/20250121150419.1342794-1-sourabhjain@linux.ibm.com/ [1]
Link: https://lore.kernel.org/all/20250128043358.163372-1-sourabhjain@linux.ibm.com/ [2]
Link: https://lkml.kernel.org/r/20251224115524.1272010-1-sourabhjain@linux.ibm.com
Fixes:
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b9efe36b5e |
mm/page_alloc: make percpu_pagelist_high_fraction reads lock-free
When page isolation loops indefinitely during memory offline, reading /proc/sys/vm/percpu_pagelist_high_fraction blocks on pcp_batch_high_lock, causing hung task warnings. Make procfs reads lock-free since percpu_pagelist_high_fraction is a simple integer with naturally atomic reads, writers still serialize via the mutex. This prevents hung task warnings when reading the procfs file during long-running memory offline operations. [akpm@linux-foundation.org: add comment, per Michal] Link: https://lkml.kernel.org/r/aS_y9AuJQFydLEXo@tiehlicka Link: https://lkml.kernel.org/r/20251201060009.1420792-1-aboorvad@linux.ibm.com Signed-off-by: Aboorva Devarajan <aboorvad@linux.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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a38be54626 |
mm/damon/core: get memcg reference before access
The commit |
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eb3f781ab7 |
mm: vmalloc: fix up vrealloc_node_align() kernel-doc macro name
Sphinx reports kernel-doc warning:
WARNING: ./mm/vmalloc.c:4284 expecting prototype for vrealloc_node_align_noprof(). Prototype was for vrealloc_node_align() instead
Fix the macro name in vrealloc_node_align_noprof() kernel-doc comment.
Link: https://lkml.kernel.org/r/20251219014006.16328-5-bagasdotme@gmail.com
Fixes:
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6626734dd2 |
mm_zone: Generalise has_managed_dma()
It would be useful to be able to check for potential DMA pages beyond just ZONE_DMA - generalise the existing has_managed_dma() function to allow checking other zones too. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Tested-by: Vladimir Kondratiev <vladimir.kondratiev@mobileye.com> Reviewed-by: Baoquan He <bhe@redhat.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/r/bd002d2351074e57be1ca08f03f333debac658fb.1768230104.git.robin.murphy@arm.com |