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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull futex fixes from Ingo Molnar:
- Tighten up the sys_futex_requeue() ABI a bit, to disallow dissimilar
futex flags and potential UaF access (Peter Zijlstra)
- Fix UaF between futex_key_to_node_opt() and vma_replace_policy()
(Hao-Yu Yang)
- Clear stale exiting pointer in futex_lock_pi() retry path, which
triggered a warning (and potential misbehavior) in stress-testing
(Davidlohr Bueso)
* tag 'locking-urgent-2026-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Clear stale exiting pointer in futex_lock_pi() retry path
futex: Fix UaF between futex_key_to_node_opt() and vma_replace_policy()
futex: Require sys_futex_requeue() to have identical flags
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git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"10 hotfixes. 8 are cc:stable. 9 are for MM.
There's a 3-patch series of DAMON fixes from Josh Law and SeongJae
Park. The rest are singletons - please see the changelogs for details"
* tag 'mm-hotfixes-stable-2026-03-28-10-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm/mseal: update VMA end correctly on merge
bug: avoid format attribute warning for clang as well
mm/pagewalk: fix race between concurrent split and refault
mm/memory: fix PMD/PUD checks in follow_pfnmap_start()
mm/damon/sysfs: check contexts->nr in repeat_call_fn
mm/damon/sysfs: check contexts->nr before accessing contexts_arr[0]
mm/damon/sysfs: fix param_ctx leak on damon_sysfs_new_test_ctx() failure
mm/swap: fix swap cache memcg accounting
MAINTAINERS, mailmap: update email address for Harry Yoo
mm/huge_memory: fix folio isn't locked in softleaf_to_folio()
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Previously we stored the end of the current VMA in curr_end, and then upon
iterating to the next VMA updated curr_start to curr_end to advance to the
next VMA.
However, this doesn't take into account the fact that a VMA might be
updated due to a merge by vma_modify_flags(), which can result in curr_end
being stale and thus, upon setting curr_start to curr_end, ending up with
an incorrect curr_start on the next iteration.
Resolve the issue by setting curr_end to vma->vm_end unconditionally to
ensure this value remains updated should this occur.
While we're here, eliminate this entire class of bug by simply setting
const curr_[start/end] to be clamped to the input range and VMAs, which
also happens to simplify the logic.
Link: https://lkml.kernel.org/r/20260327173104.322405-1-ljs@kernel.org
Fixes: 6c2da14ae1e0 ("mm/mseal: rework mseal apply logic")
Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Reported-by: Antonius <antonius@bluedragonsec.com>
Closes: https://lore.kernel.org/linux-mm/CAK8a0jwWGj9-SgFk0yKFh7i8jMkwKm5b0ao9=kmXWjO54veX2g@mail.gmail.com/
Suggested-by: David Hildenbrand (ARM) <david@kernel.org>
Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Jeff Xu <jeffxu@chromium.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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The splitting of a PUD entry in walk_pud_range() can race with a
concurrent thread refaulting the PUD leaf entry causing it to try walking
a PMD range that has disappeared.
An example and reproduction of this is to try reading numa_maps of a
process while VFIO-PCI is setting up DMA (specifically the
vfio_pin_pages_remote call) on a large BAR for that process.
This will trigger a kernel BUG:
vfio-pci 0000:03:00.0: enabling device (0000 -> 0002)
BUG: unable to handle page fault for address: ffffa23980000000
PGD 0 P4D 0
Oops: Oops: 0000 [#1] SMP NOPTI
...
RIP: 0010:walk_pgd_range+0x3b5/0x7a0
Code: 8d 43 ff 48 89 44 24 28 4d 89 ce 4d 8d a7 00 00 20 00 48 8b 4c 24
28 49 81 e4 00 00 e0 ff 49 8d 44 24 ff 48 39 c8 4c 0f 43 e3 <49> f7 06
9f ff ff ff 75 3b 48 8b 44 24 20 48 8b 40 28 48 85 c0 74
RSP: 0018:ffffac23e1ecf808 EFLAGS: 00010287
RAX: 00007f44c01fffff RBX: 00007f4500000000 RCX: 00007f44ffffffff
RDX: 0000000000000000 RSI: 000ffffffffff000 RDI: ffffffff93378fe0
RBP: ffffac23e1ecf918 R08: 0000000000000004 R09: ffffa23980000000
R10: 0000000000000020 R11: 0000000000000004 R12: 00007f44c0200000
R13: 00007f44c0000000 R14: ffffa23980000000 R15: 00007f44c0000000
FS: 00007fe884739580(0000) GS:ffff9b7d7a9c0000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffa23980000000 CR3: 000000c0650e2005 CR4: 0000000000770ef0
PKRU: 55555554
Call Trace:
<TASK>
__walk_page_range+0x195/0x1b0
walk_page_vma+0x62/0xc0
show_numa_map+0x12b/0x3b0
seq_read_iter+0x297/0x440
seq_read+0x11d/0x140
vfs_read+0xc2/0x340
ksys_read+0x5f/0xe0
do_syscall_64+0x68/0x130
? get_page_from_freelist+0x5c2/0x17e0
? mas_store_prealloc+0x17e/0x360
? vma_set_page_prot+0x4c/0xa0
? __alloc_pages_noprof+0x14e/0x2d0
? __mod_memcg_lruvec_state+0x8d/0x140
? __lruvec_stat_mod_folio+0x76/0xb0
? __folio_mod_stat+0x26/0x80
? do_anonymous_page+0x705/0x900
? __handle_mm_fault+0xa8d/0x1000
? __count_memcg_events+0x53/0xf0
? handle_mm_fault+0xa5/0x360
? do_user_addr_fault+0x342/0x640
? arch_exit_to_user_mode_prepare.constprop.0+0x16/0xa0
? irqentry_exit_to_user_mode+0x24/0x100
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fe88464f47e
Code: c0 e9 b6 fe ff ff 50 48 8d 3d be 07 0b 00 e8 69 01 02 00 66 0f 1f
84 00 00 00 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00
f0 ff ff 77 5a c3 66 0f 1f 84 00 00 00 00 00 48 83 ec 28
RSP: 002b:00007ffe6cd9a9b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007fe88464f47e
RDX: 0000000000020000 RSI: 00007fe884543000 RDI: 0000000000000003
RBP: 00007fe884543000 R08: 00007fe884542010 R09: 0000000000000000
R10: fffffffffffffbc5 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000
</TASK>
Fix this by validating the PUD entry in walk_pmd_range() using a stable
snapshot (pudp_get()). If the PUD is not present or is a leaf, retry the
walk via ACTION_AGAIN instead of descending further. This mirrors the
retry logic in walk_pte_range(), which lets walk_pmd_range() retry if the
PTE is not being got by pte_offset_map_lock().
Link: https://lkml.kernel.org/r/20260325-pagewalk-check-pmd-refault-v2-1-707bff33bc60@akamai.com
Fixes: f9e54c3a2f5b ("vfio/pci: implement huge_fault support")
Co-developed-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Max Boone <mboone@akamai.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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follow_pfnmap_start() suffers from two problems:
(1) We are not re-fetching the pmd/pud after taking the PTL
Therefore, we are not properly stabilizing what the lock actually
protects. If there is concurrent zapping, we would indicate to the
caller that we found an entry, however, that entry might already have
been invalidated, or contain a different PFN after taking the lock.
Properly use pmdp_get() / pudp_get() after taking the lock.
(2) pmd_leaf() / pud_leaf() are not well defined on non-present entries
pmd_leaf()/pud_leaf() could wrongly trigger on non-present entries.
There is no real guarantee that pmd_leaf()/pud_leaf() returns something
reasonable on non-present entries. Most architectures indeed either
perform a present check or make it work by smart use of flags.
However, for example loongarch checks the _PAGE_HUGE flag in pmd_leaf(),
and always sets the _PAGE_HUGE flag in __swp_entry_to_pmd(). Whereby
pmd_trans_huge() explicitly checks pmd_present(), pmd_leaf() does not do
that.
Let's check pmd_present()/pud_present() before assuming "the is a present
PMD leaf" when spotting pmd_leaf()/pud_leaf(), like other page table
handling code that traverses user page tables does.
Given that non-present PMD entries are likely rare in VM_IO|VM_PFNMAP, (1)
is likely more relevant than (2). It is questionable how often (1) would
actually trigger, but let's CC stable to be sure.
This was found by code inspection.
Link: https://lkml.kernel.org/r/20260323-follow_pfnmap_fix-v1-1-5b0ec10872b3@kernel.org
Fixes: 6da8e9634bb7 ("mm: new follow_pfnmap API")
Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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damon_sysfs_repeat_call_fn() calls damon_sysfs_upd_tuned_intervals(),
damon_sysfs_upd_schemes_stats(), and
damon_sysfs_upd_schemes_effective_quotas() without checking contexts->nr.
If nr_contexts is set to 0 via sysfs while DAMON is running, these
functions dereference contexts_arr[0] and cause a NULL pointer
dereference. Add the missing check.
For example, the issue can be reproduced using DAMON sysfs interface and
DAMON user-space tool (damo) [1] like below.
$ sudo damo start --refresh_interval 1s
$ echo 0 | sudo tee \
/sys/kernel/mm/damon/admin/kdamonds/0/contexts/nr_contexts
Link: https://patch.msgid.link/20260320163559.178101-3-objecting@objecting.org
Link: https://lkml.kernel.org/r/20260321175427.86000-4-sj@kernel.org
Link: https://github.com/damonitor/damo [1]
Fixes: d809a7c64ba8 ("mm/damon/sysfs: implement refresh_ms file internal work")
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> [6.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Multiple sysfs command paths dereference contexts_arr[0] without first
verifying that kdamond->contexts->nr == 1. A user can set nr_contexts to
0 via sysfs while DAMON is running, causing NULL pointer dereferences.
In more detail, the issue can be triggered by privileged users like
below.
First, start DAMON and make contexts directory empty
(kdamond->contexts->nr == 0).
# damo start
# cd /sys/kernel/mm/damon/admin/kdamonds/0
# echo 0 > contexts/nr_contexts
Then, each of below commands will cause the NULL pointer dereference.
# echo update_schemes_stats > state
# echo update_schemes_tried_regions > state
# echo update_schemes_tried_bytes > state
# echo update_schemes_effective_quotas > state
# echo update_tuned_intervals > state
Guard all commands (except OFF) at the entry point of
damon_sysfs_handle_cmd().
Link: https://lkml.kernel.org/r/20260321175427.86000-3-sj@kernel.org
Fixes: 0ac32b8affb5 ("mm/damon/sysfs: support DAMOS stats")
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> [5.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Patch series "mm/damon/sysfs: fix memory leak and NULL dereference
issues", v4.
DAMON_SYSFS can leak memory under allocation failure, and do NULL pointer
dereference when a privileged user make wrong sequences of control. Fix
those.
This patch (of 3):
When damon_sysfs_new_test_ctx() fails in damon_sysfs_commit_input(),
param_ctx is leaked because the early return skips the cleanup at the out
label. Destroy param_ctx before returning.
Link: https://lkml.kernel.org/r/20260321175427.86000-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20260321175427.86000-2-sj@kernel.org
Fixes: f0c5118ebb0e ("mm/damon/sysfs: catch commit test ctx alloc failure")
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> [6.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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The swap readahead path was recently refactored and while doing this, the
order between the charging of the folio in the memcg and the addition of
the folio in the swap cache was inverted.
Since the accounting of the folio is done while adding the folio to the
swap cache and the folio is not charged in the memcg yet, the accounting
is then done at the node level, which is wrong.
Fix this by charging the folio in the memcg before adding it to the swap cache.
Link: https://lkml.kernel.org/r/20260320050601.1833108-1-alex@ghiti.fr
Fixes: 2732acda82c9 ("mm, swap: use swap cache as the swap in synchronize layer")
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: Kairui Song <kasong@tencent.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Acked-by: Chris Li <chrisl@kernel.org>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux
Pull dma-mapping fixes from Marek Szyprowski:
"A set of fixes for DMA-mapping subsystem, which resolve false-
positive warnings from KMSAN and DMA-API debug (Shigeru Yoshida
and Leon Romanovsky) as well as a simple build fix (Miguel Ojeda)"
* tag 'dma-mapping-7.0-2026-03-25' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
dma-mapping: add missing `inline` for `dma_free_attrs`
mm/hmm: Indicate that HMM requires DMA coherency
RDMA/umem: Tell DMA mapping that UMEM requires coherency
iommu/dma: add support for DMA_ATTR_REQUIRE_COHERENT attribute
dma-direct: prevent SWIOTLB path when DMA_ATTR_REQUIRE_COHERENT is set
dma-mapping: Introduce DMA require coherency attribute
dma-mapping: Clarify valid conditions for CPU cache line overlap
dma-mapping: handle DMA_ATTR_CPU_CACHE_CLEAN in trace output
dma-debug: Allow multiple invocations of overlapping entries
dma: swiotlb: add KMSAN annotations to swiotlb_bounce()
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During futex_key_to_node_opt() execution, vma->vm_policy is read under
speculative mmap lock and RCU. Concurrently, mbind() may call
vma_replace_policy() which frees the old mempolicy immediately via
kmem_cache_free().
This creates a race where __futex_key_to_node() dereferences a freed
mempolicy pointer, causing a use-after-free read of mpol->mode.
[ 151.412631] BUG: KASAN: slab-use-after-free in __futex_key_to_node (kernel/futex/core.c:349)
[ 151.414046] Read of size 2 at addr ffff888001c49634 by task e/87
[ 151.415969] Call Trace:
[ 151.416732] __asan_load2 (mm/kasan/generic.c:271)
[ 151.416777] __futex_key_to_node (kernel/futex/core.c:349)
[ 151.416822] get_futex_key (kernel/futex/core.c:374 kernel/futex/core.c:386 kernel/futex/core.c:593)
Fix by adding rcu to __mpol_put().
Fixes: c042c505210d ("futex: Implement FUTEX2_MPOL")
Reported-by: Hao-Yu Yang <naup96721@gmail.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Hao-Yu Yang <naup96721@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Link: https://patch.msgid.link/20260324174418.GB1850007@noisy.programming.kicks-ass.net
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DAMON_STAT usage document (Documentation/admin-guide/mm/damon/stat.rst)
says it monitors the system's entire physical memory. But, it is
monitoring only the biggest System RAM resource of the system. When there
are multiple System RAM resources, this results in monitoring only an
unexpectedly small fraction of the physical memory. For example, suppose
the system has a 500 GiB System RAM, 10 MiB non-System RAM, and 500 GiB
System RAM resources in order on the physical address space. DAMON_STAT
will monitor only the first 500 GiB System RAM. This situation is
particularly common on NUMA systems.
Select a physical address range that covers all System RAM areas of the
system, to fix this issue and make it work as documented.
[sj@kernel.org: return error if monitoring target region is invalid]
Link: https://lkml.kernel.org/r/20260317053631.87907-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20260316235118.873-1-sj@kernel.org
Fixes: 369c415e6073 ("mm/damon: introduce DAMON_STAT module")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> [6.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Commit e2c3b6b21c77 ("mm: zswap: use SG list decompression APIs from
zsmalloc") updated zswap_decompress() to use the scatterwalk API to copy
data for uncompressed pages.
In doing so, it mapped kernel memory locally for 32-bit kernels using
kmap_local_folio(), however it never unmapped this memory.
This resulted in the linked syzbot report where a BUG_ON() is triggered
due to leaking the kmap slot.
This patch fixes the issue by explicitly unmapping the established kmap.
Also, add flush_dcache_folio() after the kunmap_local() call
I had assumed that a new folio here combined with the flush that is done at
the point of setting the PTE would suffice, but it doesn't seem that's
actually the case, as update_mmu_cache() will in many archtectures only
actually flush entries where a dcache flush was done on a range previously.
I had also wondered whether kunmap_local() might suffice, but it doesn't
seem to be the case.
Some arches do seem to actually dcache flush on unmap, parisc does it if
CONFIG_HIGHMEM is not set by setting ARCH_HAS_FLUSH_ON_KUNMAP and calling
kunmap_flush_on_unmap() from __kunmap_local(), otherwise non-CONFIG_HIGHMEM
callers do nothing here.
Otherwise arch_kmap_local_pre_unmap() is called which does:
* sparc - flush_cache_all()
* arm - if VIVT, __cpuc_flush_dcache_area()
* otherwise - nothing
Also arch_kmap_local_post_unmap() is called which does:
* arm - local_flush_tlb_kernel_page()
* csky - kmap_flush_tlb()
* microblaze, ppc - local_flush_tlb_page()
* mips - local_flush_tlb_one()
* sparc - flush_tlb_all() (again)
* x86 - arch_flush_lazy_mmu_mode()
* otherwise - nothing
But this is only if it's high memory, and doesn't cover all architectures,
so is presumably intended to handle other cache consistency concerns.
In any case, VIPT is problematic here whether low or high memory (in spite
of what the documentation claims, see [0] - 'the kernel did write to a page
that is in the page cache page and / or in high memory'), because dirty
cache lines may exist at the set indexed by the kernel direct mapping,
which won't exist in the set indexed by any subsequent userland mapping,
meaning userland might read stale data from L2 cache.
Even if the documentation is correct and low memory is fine not to be
flushed here, we can't be sure as to whether the memory is low or high
(kmap_local_folio() will be a no-op if low), and this call should be
harmless if it is low.
VIVT would require more work if the memory were shared and already mapped,
but this isn't the case here, and would anyway be handled by the dcache
flush call.
In any case, we definitely need this flush as far as I can tell.
And we should probably consider updating the documentation unless it turns
out there's somehow dcache synchronisation that happens for low
memory/64-bit kernels elsewhere?
[ljs@kernel.org: add flush_dcache_folio() after the kunmap_local() call]
Link: https://lkml.kernel.org/r/13e09a99-181f-45ac-a18d-057faf94bccb@lucifer.local
Link: https://lkml.kernel.org/r/20260316140122.339697-1-ljs@kernel.org
Link: https://docs.kernel.org/core-api/cachetlb.html [0]
Fixes: e2c3b6b21c77 ("mm: zswap: use SG list decompression APIs from zsmalloc")
Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Reported-by: syzbot+fe426bef95363177631d@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/69b75e2c.050a0220.12d28.015a.GAE@google.com
Acked-by: Yosry Ahmed <yosry@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Acked-by: Yosry Ahmed <yosry@kernel.org>
Acked-by: Nhat Pham <nphamcs@gmail.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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One major usage of damon_call() is online DAMON parameters update. It is
done by calling damon_commit_ctx() inside the damon_call() callback
function. damon_commit_ctx() can fail for two reasons: 1) invalid
parameters and 2) internal memory allocation failures. In case of
failures, the damon_ctx that attempted to be updated (commit destination)
can be partially updated (or, corrupted from a perspective), and therefore
shouldn't be used anymore. The function only ensures the damon_ctx object
can safely deallocated using damon_destroy_ctx().
The API callers are, however, calling damon_commit_ctx() only after
asserting the parameters are valid, to avoid damon_commit_ctx() fails due
to invalid input parameters. But it can still theoretically fail if the
internal memory allocation fails. In the case, DAMON may run with the
partially updated damon_ctx. This can result in unexpected behaviors
including even NULL pointer dereference in case of damos_commit_dests()
failure [1]. Such allocation failure is arguably too small to fail, so
the real world impact would be rare. But, given the bad consequence, this
needs to be fixed.
Avoid such partially-committed (maybe-corrupted) damon_ctx use by saving
the damon_commit_ctx() failure on the damon_ctx object. For this,
introduce damon_ctx->maybe_corrupted field. damon_commit_ctx() sets it
when it is failed. kdamond_call() checks if the field is set after each
damon_call_control->fn() is executed. If it is set, ignore remaining
callback requests and return. All kdamond_call() callers including
kdamond_fn() also check the maybe_corrupted field right after
kdamond_call() invocations. If the field is set, break the kdamond_fn()
main loop so that DAMON sill doesn't use the context that might be
corrupted.
[sj@kernel.org: let kdamond_call() with cancel regardless of maybe_corrupted]
Link: https://lkml.kernel.org/r/20260320031553.2479-1-sj@kernel.org
Link: https://sashiko.dev/#/patchset/20260319145218.86197-1-sj%40kernel.org
Link: https://lkml.kernel.org/r/20260319145218.86197-1-sj@kernel.org
Link: https://lore.kernel.org/20260319043309.97966-1-sj@kernel.org [1]
Fixes: 3301f1861d34 ("mm/damon/sysfs: handle commit command using damon_call()")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> [6.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Commit 542eda1a8329 ("mm/rmap: improve anon_vma_clone(),
unlink_anon_vmas() comments, add asserts") alters the way errors are
handled, but overlooked one important aspect of clean up.
When a VMA encounters an error state in anon_vma_clone() (that is, on
attempted allocation of anon_vma_chain objects), it cleans up partially
established state in cleanup_partial_anon_vmas(), before returning an
error.
However, this occurs prior to anon_vma->num_active_vmas being incremented,
and it also fails to clear the VMA's vma->anon_vma field, which remains in
place.
This is immediately an inconsistent state, because
anon_vma->num_active_vmas is supposed to track the number of VMAs whose
vma->anon_vma field references that anon_vma, and now that count is
off-by-negative-1 for each VMA for which this error state has occurred.
When VMAs are unlinked from this anon_vma, unlink_anon_vmas() will
eventually underflow anon_vma->num_active_vmas, which will trigger a
warning.
This will always eventually happen, as we unlink anon_vma's at process
teardown.
It could also cause maybe_reuse_anon_vma() to incorrectly permit the reuse
of an anon_vma which has active VMAs attached, which will lead to a
persistently invalid state.
The solution is to clear the VMA's anon_vma field when we clean up partial
state, as the fact we are doing so indicates clearly that the VMA is not
correctly integrated into the anon_vma tree and thus this field is
invalid.
Link: https://lkml.kernel.org/r/20260318122632.63404-1-ljs@kernel.org
Fixes: 542eda1a8329 ("mm/rmap: improve anon_vma_clone(), unlink_anon_vmas() comments, add asserts")
Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Reported-by: Sasha Levin <sashal@kernel.org>
Closes: https://lore.kernel.org/linux-mm/20260302151547.2389070-1-sashal@kernel.org/
Reported-by: Jiakai Xu <jiakaipeanut@gmail.com>
Closes: https://lore.kernel.org/linux-mm/CAFb8wJvRhatRD-9DVmr5v5pixTMPEr3UKjYBJjCd09OfH55CKg@mail.gmail.com/
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Tested-by: Jiakai Xu <jiakaipeanut@gmail.com>
Acked-by: Harry Yoo <harry.yoo@oracle.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Sasha Levin (Microsoft) <sashal@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
HMM is fundamentally about allowing a sophisticated device to perform DMA
directly to a process’s memory while the CPU accesses that same memory at
the same time. It is similar to SVA but does not rely on IOMMU support.
Because the entire model depends on concurrent access to shared memory, it
fails as a uAPI if SWIOTLB substitutes the memory or if the CPU caches are
not coherent with DMA.
Until now, there has been no reliable way to report this, and various
approximations have been used:
int hmm_dma_map_alloc(struct device *dev, struct hmm_dma_map *map,
size_t nr_entries, size_t dma_entry_size)
{
<...>
/*
* The HMM API violates our normal DMA buffer ownership rules and can't
* transfer buffer ownership. The dma_addressing_limited() check is a
* best approximation to ensure no swiotlb buffering happens.
*/
dma_need_sync = !dev->dma_skip_sync;
if (dma_need_sync || dma_addressing_limited(dev))
return -EOPNOTSUPP;
So let's mark mapped buffers with DMA_ATTR_REQUIRE_COHERENT attribute
to prevent silent data corruption if someone tries to use hmm in a system
with swiotlb or incoherent DMA
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20260316-dma-debug-overlap-v3-8-1dde90a7f08b@nvidia.com
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"6 hotfixes. 4 are cc:stable. 3 are for MM.
All are singletons - please see the changelogs for details"
* tag 'mm-hotfixes-stable-2026-03-16-12-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
MAINTAINERS: update email address for Ignat Korchagin
mm/huge_memory: fix early failure try_to_migrate() when split huge pmd for shared THP
mm/rmap: fix incorrect pte restoration for lazyfree folios
mm/huge_memory: fix use of NULL folio in move_pages_huge_pmd()
build_bug.h: correct function parameters names in kernel-doc
crash_dump: don't log dm-crypt key bytes in read_key_from_user_keying
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab fixes from Vlastimil Babka:
- Fix for a memory leak that can occur when already so low on memory
that we can't allocate a new slab anymore (Qing Wang)
- Fix for a case where slabobj_ext array for a slab might be allocated
from the same slab, making it permanently non-freeable (Harry Yoo)
* tag 'slab-for-7.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
slab: fix memory leak when refill_sheaf() fails
mm/slab: fix an incorrect check in obj_exts_alloc_size()
|
|
When refill_sheaf() partially fills one sheaf (e.g., fills 5 objects
but need to fill 10), it will update sheaf->size and return -ENOMEM.
However, the callers (alloc_full_sheaf() and __pcs_replace_empty_main())
directly call free_empty_sheaf() on failure, which only does kfree(sheaf),
causing the partially allocated objects memory in sheaf->objects[] leaked.
Fix this by calling sheaf_flush_unused() before free_empty_sheaf() to
free objects of sheaf->objects[]. And also add a WARN_ON() in
free_empty_sheaf() to catch any future cases where a non-empty sheaf is
being freed.
Fixes: ed30c4adfc2b ("slab: add optimized sheaf refill from partial list")
Signed-off-by: Qing Wang <wangqing7171@gmail.com>
Link: https://patch.msgid.link/20260311093617.4155965-1-wangqing7171@gmail.com
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Hao Li <hao.li@linux.dev>
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
|
|
shared THP
Commit 60fbb14396d5 ("mm/huge_memory: adjust try_to_migrate_one() and
split_huge_pmd_locked()") return false unconditionally after
split_huge_pmd_locked(). This may fail try_to_migrate() early when
TTU_SPLIT_HUGE_PMD is specified.
The reason is the above commit adjusted try_to_migrate_one() to, when a
PMD-mapped THP entry is found, and TTU_SPLIT_HUGE_PMD is specified (for
example, via unmap_folio()), return false unconditionally. This breaks
the rmap walk and fail try_to_migrate() early, if this PMD-mapped THP is
mapped in multiple processes.
The user sensible impact of this bug could be:
* On memory pressure, shrink_folio_list() may split partially mapped
folio with split_folio_to_list(). Then free unmapped pages without IO.
If failed, it may not be reclaimed.
* On memory failure, memory_failure() would call try_to_split_thp_page()
to split folio contains the bad page. If succeed, the PG_has_hwpoisoned
bit is only set in the after-split folio contains @split_at. By doing
so, we limit bad memory. If failed to split, the whole folios is not
usable.
One way to reproduce:
Create an anonymous THP range and fork 512 children, so we have a
THP shared mapped in 513 processes. Then trigger folio split with
/sys/kernel/debug/split_huge_pages debugfs to split the THP folio to
order 0.
Without the above commit, we can successfully split to order 0. With the
above commit, the folio is still a large folio.
And currently there are two core users of TTU_SPLIT_HUGE_PMD:
* try_to_unmap_one()
* try_to_migrate_one()
try_to_unmap_one() would restart the rmap walk, so only
try_to_migrate_one() is affected.
We can't simply revert commit 60fbb14396d5 ("mm/huge_memory: adjust
try_to_migrate_one() and split_huge_pmd_locked()"), since it removed some
duplicated check covered by page_vma_mapped_walk().
This patch fixes this by restart page_vma_mapped_walk() after
split_huge_pmd_locked(). Since we cannot simply return "true" to fix the
problem, as that would affect another case:
When invoking folio_try_share_anon_rmap_pmd() from
split_huge_pmd_locked(), the latter can fail and leave a large folio
mapped through PTEs, in which case we ought to return true from
try_to_migrate_one(). This might result in unnecessary walking of the
rmap but is relatively harmless.
Link: https://lkml.kernel.org/r/20260305015006.27343-1-richard.weiyang@gmail.com
Fixes: 60fbb14396d5 ("mm/huge_memory: adjust try_to_migrate_one() and split_huge_pmd_locked()")
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Tested-by: Lance Yang <lance.yang@linux.dev>
Reviewed-by: Lance Yang <lance.yang@linux.dev>
Reviewed-by: Gavin Guo <gavinguo@igalia.com>
Acked-by: David Hildenbrand (arm) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
We batch unmap anonymous lazyfree folios by folio_unmap_pte_batch. If the
batch has a mix of writable and non-writable bits, we may end up setting
the entire batch writable. Fix this by respecting writable bit during
batching.
Although on a successful unmap of a lazyfree folio, the soft-dirty bit is
lost, preserve it on pte restoration by respecting the bit during
batching, to make the fix consistent w.r.t both writable bit and
soft-dirty bit.
I was able to write the below reproducer and crash the kernel.
Explanation of reproducer (set 64K mTHP to always):
Fault in a 64K large folio. Split the VMA at mid-point with
MADV_DONTFORK. fork() - parent points to the folio with 8 writable ptes
and 8 non-writable ptes. Merge the VMAs with MADV_DOFORK so that
folio_unmap_pte_batch() can determine all the 16 ptes as a batch. Do
MADV_FREE on the range to mark the folio as lazyfree. Write to the memory
to dirty the pte, eventually rmap will dirty the folio. Then trigger
reclaim, we will hit the pte restoration path, and the kernel will crash
with the trace given below.
The BUG happens at:
BUG_ON(atomic_inc_return(&ptc->anon_map_count) > 1 && rw);
The code path is asking for anonymous page to be mapped writable into the
pagetable. The BUG_ON() firing implies that such a writable page has been
mapped into the pagetables of more than one process, which breaks
anonymous memory/CoW semantics.
[ 21.134473] kernel BUG at mm/page_table_check.c:118!
[ 21.134497] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
[ 21.135917] Modules linked in:
[ 21.136085] CPU: 1 UID: 0 PID: 1735 Comm: dup-lazyfree Not tainted 7.0.0-rc1-00116-g018018a17770 #1028 PREEMPT
[ 21.136858] Hardware name: linux,dummy-virt (DT)
[ 21.137019] pstate: 21400005 (nzCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
[ 21.137308] pc : page_table_check_set+0x28c/0x2a8
[ 21.137607] lr : page_table_check_set+0x134/0x2a8
[ 21.137885] sp : ffff80008a3b3340
[ 21.138124] x29: ffff80008a3b3340 x28: fffffdffc3d14400 x27: ffffd1a55e03d000
[ 21.138623] x26: 0040000000000040 x25: ffffd1a55f7dd000 x24: 0000000000000001
[ 21.139045] x23: 0000000000000001 x22: 0000000000000001 x21: ffffd1a55f217f30
[ 21.139629] x20: 0000000000134521 x19: 0000000000134519 x18: 005c43e000040000
[ 21.140027] x17: 0001400000000000 x16: 0001700000000000 x15: 000000000000ffff
[ 21.140578] x14: 000000000000000c x13: 005c006000000000 x12: 0000000000000020
[ 21.140828] x11: 0000000000000000 x10: 005c000000000000 x9 : ffffd1a55c079ee0
[ 21.141077] x8 : 0000000000000001 x7 : 005c03e000040000 x6 : 000000004000ffff
[ 21.141490] x5 : ffff00017fffce00 x4 : 0000000000000001 x3 : 0000000000000002
[ 21.141741] x2 : 0000000000134510 x1 : 0000000000000000 x0 : ffff0000c08228c0
[ 21.141991] Call trace:
[ 21.142093] page_table_check_set+0x28c/0x2a8 (P)
[ 21.142265] __page_table_check_ptes_set+0x144/0x1e8
[ 21.142441] __set_ptes_anysz.constprop.0+0x160/0x1a8
[ 21.142766] contpte_set_ptes+0xe8/0x140
[ 21.142907] try_to_unmap_one+0x10c4/0x10d0
[ 21.143177] rmap_walk_anon+0x100/0x250
[ 21.143315] try_to_unmap+0xa0/0xc8
[ 21.143441] shrink_folio_list+0x59c/0x18a8
[ 21.143759] shrink_lruvec+0x664/0xbf0
[ 21.144043] shrink_node+0x218/0x878
[ 21.144285] __node_reclaim.constprop.0+0x98/0x338
[ 21.144763] user_proactive_reclaim+0x2a4/0x340
[ 21.145056] reclaim_store+0x3c/0x60
[ 21.145216] dev_attr_store+0x20/0x40
[ 21.145585] sysfs_kf_write+0x84/0xa8
[ 21.145835] kernfs_fop_write_iter+0x130/0x1c8
[ 21.145994] vfs_write+0x2b8/0x368
[ 21.146119] ksys_write+0x70/0x110
[ 21.146240] __arm64_sys_write+0x24/0x38
[ 21.146380] invoke_syscall+0x50/0x120
[ 21.146513] el0_svc_common.constprop.0+0x48/0xf8
[ 21.146679] do_el0_svc+0x28/0x40
[ 21.146798] el0_svc+0x34/0x110
[ 21.146926] el0t_64_sync_handler+0xa0/0xe8
[ 21.147074] el0t_64_sync+0x198/0x1a0
[ 21.147225] Code: f9400441 b4fff241 17ffff94 d4210000 (d4210000)
[ 21.147440] ---[ end trace 0000000000000000 ]---
#define _GNU_SOURCE
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <string.h>
#include <sys/wait.h>
#include <sched.h>
#include <fcntl.h>
void write_to_reclaim() {
const char *path = "/sys/devices/system/node/node0/reclaim";
const char *value = "409600000000";
int fd = open(path, O_WRONLY);
if (fd == -1) {
perror("open");
exit(EXIT_FAILURE);
}
if (write(fd, value, sizeof("409600000000") - 1) == -1) {
perror("write");
close(fd);
exit(EXIT_FAILURE);
}
printf("Successfully wrote %s to %s\n", value, path);
close(fd);
}
int main()
{
char *ptr = mmap((void *)(1UL << 30), 1UL << 16, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if ((unsigned long)ptr != (1UL << 30)) {
perror("mmap");
return 1;
}
/* a 64K folio gets faulted in */
memset(ptr, 0, 1UL << 16);
/* 32K half will not be shared into child */
if (madvise(ptr, 1UL << 15, MADV_DONTFORK)) {
perror("madvise madv dontfork");
return 1;
}
pid_t pid = fork();
if (pid < 0) {
perror("fork");
return 1;
} else if (pid == 0) {
sleep(15);
} else {
/* merge VMAs. now first half of the 16 ptes are writable, the other half not. */
if (madvise(ptr, 1UL << 15, MADV_DOFORK)) {
perror("madvise madv fork");
return 1;
}
if (madvise(ptr, (1UL << 16), MADV_FREE)) {
perror("madvise madv free");
return 1;
}
/* dirty the large folio */
(*ptr) += 10;
write_to_reclaim();
// sleep(10);
waitpid(pid, NULL, 0);
}
}
Link: https://lkml.kernel.org/r/20260303061528.2429162-1-dev.jain@arm.com
Fixes: 354dffd29575 ("mm: support batched unmap for lazyfree large folios during reclamation")
Signed-off-by: Dev Jain <dev.jain@arm.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Barry Song <baohua@kernel.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Tested-by: Lance Yang <lance.yang@linux.dev>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Harry Yoo <harry.yoo@oracle.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
move_pages_huge_pmd() handles UFFDIO_MOVE for both normal THPs and huge
zero pages. For the huge zero page path, src_folio is explicitly set to
NULL, and is used as a sentinel to skip folio operations like lock and
rmap.
In the huge zero page branch, src_folio is NULL, so folio_mk_pmd(NULL,
pgprot) passes NULL through folio_pfn() and page_to_pfn(). With
SPARSEMEM_VMEMMAP this silently produces a bogus PFN, installing a PMD
pointing to non-existent physical memory. On other memory models it is a
NULL dereference.
Use page_folio(src_page) to obtain the valid huge zero folio from the
page, which was obtained from pmd_page() and remains valid throughout.
After commit d82d09e48219 ("mm/huge_memory: mark PMD mappings of the huge
zero folio special"), moved huge zero PMDs must remain special so
vm_normal_page_pmd() continues to treat them as special mappings.
move_pages_huge_pmd() currently reconstructs the destination PMD in the
huge zero page branch, which drops PMD state such as pmd_special() on
architectures with CONFIG_ARCH_HAS_PTE_SPECIAL. As a result,
vm_normal_page_pmd() can treat the moved huge zero PMD as a normal page
and corrupt its refcount.
Instead of reconstructing the PMD from the folio, derive the destination
entry from src_pmdval after pmdp_huge_clear_flush(), then handle the PMD
metadata the same way move_huge_pmd() does for moved entries by marking it
soft-dirty and clearing uffd-wp.
Link: https://lkml.kernel.org/r/a1e787dd-b911-474d-8570-f37685357d86@lucifer.local
Fixes: e3981db444a0 ("mm: add folio_mk_pmd()")
Signed-off-by: Chris Down <chris@chrisdown.name>
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Tested-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"15 hotfixes. 6 are cc:stable. 14 are for MM.
Singletons, with one doubleton - please see the changelogs for details"
* tag 'mm-hotfixes-stable-2026-03-09-16-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
MAINTAINERS, mailmap: update email address for Lorenzo Stoakes
mm/mmu_notifier: clean up mmu_notifier.h kernel-doc
uaccess: correct kernel-doc parameter format
mm/huge_memory: fix a folio_split() race condition with folio_try_get()
MAINTAINERS: add co-maintainer and reviewer for SLAB ALLOCATOR
MAINTAINERS: add RELAY entry
memcg: fix slab accounting in refill_obj_stock() trylock path
mm/hugetlb.c: use __pa() instead of virt_to_phys() in early bootmem alloc code
zram: rename writeback_compressed device attr
tools/testing: fix testing/vma and testing/radix-tree build
Revert "ptdesc: remove references to folios from __pagetable_ctor() and pagetable_dtor()"
mm/cma: move put_page_testzero() out of VM_WARN_ON in cma_release()
mm/damon/core: clear walk_control on inactive context in damos_walk()
mm: memfd_luo: always dirty all folios
mm: memfd_luo: always make all folios uptodate
|
|
obj_exts_alloc_size() prevents recursive allocation of slabobj_ext
array from the same cache, to avoid creating slabs that are never freed.
There is one mistake that returns the original size when memory
allocation profiling is disabled. The assumption was that
memcg-triggered slabobj_ext allocation is always served from
KMALLOC_CGROUP type. But this is wrong [1]: when the caller specifies
both __GFP_RECLAIMABLE and __GFP_ACCOUNT with SLUB_TINY enabled, the
allocation is served from normal kmalloc. This is because kmalloc_type()
prioritizes __GFP_RECLAIMABLE over __GFP_ACCOUNT, and SLUB_TINY aliases
KMALLOC_RECLAIM with KMALLOC_NORMAL.
As a result, the recursion guard is bypassed and the problematic slabs
can be created. Fix this by removing the mem_alloc_profiling_enabled()
check entirely. The remaining is_kmalloc_normal() check is still
sufficient to detect whether the cache is of KMALLOC_NORMAL type and
avoid bumping the size if it's not.
Without SLUB_TINY, no functional change intended.
With SLUB_TINY, allocations with __GFP_ACCOUNT|__GFP_RECLAIMABLE
now allocate a larger array if the sizes equal.
Reported-by: Zw Tang <shicenci@gmail.com>
Fixes: 280ea9c3154b ("mm/slab: avoid allocating slabobj_ext array from its own slab")
Closes: https://lore.kernel.org/linux-mm/CAPHJ_VKuMKSke8b11AZQw1PTSFN4n2C0gFxC6xGOG0ZLHgPmnA@mail.gmail.com [1]
Cc: stable@vger.kernel.org
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Link: https://patch.msgid.link/20260309072219.22653-1-harry.yoo@oracle.com
Tested-by: Zw Tang <shicenci@gmail.com>
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
|
|
Pull drm fixes from Dave Airlie:
"Weekly fixes pull.
There is one mm fix in here for a HMM livelock triggered by the xe
driver tests. Otherwise it's a pretty wide range of fixes across the
board, ttm UAF regression fix, amdgpu fixes, nouveau doesn't crash my
laptop anymore fix, and a fair bit of misc.
Seems about right for rc3.
mm:
- mm: Fix a hmm_range_fault() livelock / starvation problem
pagemap:
- Revert "drm/pagemap: Disable device-to-device migration"
ttm:
- fix function return breaking reclaim
- fix build failure on PREEMPT_RT
- fix bo->resource UAF
dma-buf:
- include ioctl.h in uapi header
sched:
- fix kernel doc warning
amdgpu:
- LUT fixes
- VCN5 fix
- Dispclk fix
- SMU 13.x fix
- Fix race in VM acquire
- PSP 15.x fix
- UserQ fix
amdxdna:
- fix invalid payload for failed command
- fix NULL ptr dereference
- fix major fw version check
- avoid inconsistent fw state on error
i915/display:
- Fix for Lenovo T14 G7 display not refreshing
xe:
- Do not preempt fence signaling CS instructions
- Some leak and finalization fixes
- Workaround fix
nouveau:
- avoid runtime suspend oops when using dp aux
panthor:
- fix gem_sync argument ordering
solomon:
- fix incorrect display output
renesas:
- fix DSI divider programming
ethosu:
- fix job submit error clean-up refcount
- fix NPU_OP_ELEMENTWISE validation
- handle possible underflows in IFM size calcs"
* tag 'drm-fixes-2026-03-07' of https://gitlab.freedesktop.org/drm/kernel: (38 commits)
accel: ethosu: Handle possible underflow in IFM size calculations
accel: ethosu: Fix NPU_OP_ELEMENTWISE validation with scalar
accel: ethosu: Fix job submit error clean-up refcount underflows
accel/amdxdna: Split mailbox channel create function
drm/panthor: Correct the order of arguments passed to gem_sync
Revert "drm/syncobj: Fix handle <-> fd ioctls with dirty stack"
drm/ttm: Fix bo resource use-after-free
nouveau/dpcd: return EBUSY for aux xfer if the device is asleep
accel/amdxdna: Fix major version check on NPU1 platform
drm/amdgpu/userq: refcount userqueues to avoid any race conditions
drm/amdgpu/userq: Consolidate wait ioctl exit path
drm/amdgpu/psp: Use Indirect access address for GFX to PSP mailbox
drm/amdgpu: Fix use-after-free race in VM acquire
drm/amd/pm: remove invalid gpu_metrics.energy_accumulator on smu v13.0.x
drm/xe: Fix memory leak in xe_vm_madvise_ioctl
drm/xe/reg_sr: Fix leak on xa_store failure
drm/xe/xe2_hpg: Correct implementation of Wa_16025250150
drm/xe/gsc: Fix GSC proxy cleanup on early initialization failure
Revert "drm/pagemap: Disable device-to-device migration"
drm/i915/psr: Fix for Panel Replay X granularity DPCD register handling
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab fixes from Vlastimil Babka:
- Fix for slab->stride truncation on 64k page systems due to short
type. It was not due to races and lack of barriers in the end. (Harry
Yoo)
- Fix for severe performance regression due to unnecessary sheaf refill
restrictions exposed by mempool allocation strategy. (Vlastimil
Babka)
- Stable fix for potential silent percpu sheaf flushing failures on
PREEMPT_RT. (Vlastimil Babka)
* tag 'slab-for-7.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
mm/slab: change stride type from unsigned short to unsigned int
mm/slab: allow sheaf refill if blocking is not allowed
slab: distinguish lock and trylock for sheaf_flush_main()
|
|
This came up as a result of the tracing fix pull request, and commit
e39bb9e02b68 ("tracing: Fix WARN_ON in tracing_buffers_mmap_close") in
particular.
The use of MADV_DOFORK confused the ring buffer mapping reference
counting just because it was unexpected, since the mapping was
originally done with VM_DONTCOPY.
The tracing code may well be the only case of this (and fixed it all by
just using the mmap open callback to unconfuse itself), but it's just
strange that we allow MADV_DOFORK on special mappings where the kernel
has set the "don't copy this" bit.
The code already disallowed it for VM_IO mappings (going back to the
original commit f822566165dd: "madvise MADV_DONTFORK/MADV_DOFORK"), so
just extend it to any of the VM_SPECIAL cases (which includes
VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP in addition to VM_IO).
We could also allow MADV_DOFORK only on mappings that had been marked
DONTFORK by the user. But that would require us to track that
(presumably with another VM_xyz bit), so let's just do this trivial and
straightforward modifications.
If anybody notices, Lorenzo will be boarding Flying Pig Airlines.
Suggested-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Link: https://lore.kernel.org/all/a8907468-d7e9-4727-af28-66d905093230@kernel.org/
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
During a pagecache folio split, the values in the related xarray should
not be changed from the original folio at xarray split time until all
after-split folios are well formed and stored in the xarray. Current use
of xas_try_split() in __split_unmapped_folio() lets some after-split
folios show up at wrong indices in the xarray. When these misplaced
after-split folios are unfrozen, before correct folios are stored via
__xa_store(), and grabbed by folio_try_get(), they are returned to
userspace at wrong file indices, causing data corruption. More detailed
explanation is at the bottom.
The reproducer is at: https://github.com/dfinity/thp-madv-remove-test
It
1. creates a memfd,
2. forks,
3. in the child process, maps the file with large folios (via shmem code
path) and reads the mapped file continuously with 16 threads,
4. in the parent process, uses madvise(MADV_REMOVE) to punch poles in the
large folio.
Data corruption can be observed without the fix. Basically, data from a
wrong page->index is returned.
Fix it by using the original folio in xas_try_split() calls, so that
folio_try_get() can get the right after-split folios after the original
folio is unfrozen.
Uniform split, split_huge_page*(), is not affected, since it uses
xas_split_alloc() and xas_split() only once and stores the original folio
in the xarray. Change xas_split() used in uniform split branch to use the
original folio to avoid confusion.
Fixes below points to the commit introduces the code, but folio_split() is
used in a later commit 7460b470a131f ("mm/truncate: use folio_split() in
truncate operation").
More details:
For example, a folio f is split non-uniformly into f, f2, f3, f4 like
below:
+----------------+---------+----+----+
| f | f2 | f3 | f4 |
+----------------+---------+----+----+
but the xarray would look like below after __split_unmapped_folio() is
done:
+----------------+---------+----+----+
| f | f2 | f3 | f3 |
+----------------+---------+----+----+
After __split_unmapped_folio(), the code changes the xarray and unfreezes
after-split folios:
1. unfreezes f2, __xa_store(f2)
2. unfreezes f3, __xa_store(f3)
3. unfreezes f4, __xa_store(f4), which overwrites the second f3 to f4.
4. unfreezes f.
Meanwhile, a parallel filemap_get_entry() can read the second f3 from the
xarray and use folio_try_get() on it at step 2 when f3 is unfrozen. Then,
f3 is wrongly returned to user.
After the fix, the xarray looks like below after __split_unmapped_folio():
+----------------+---------+----+----+
| f | f | f | f |
+----------------+---------+----+----+
so that the race window no longer exists.
[ziy@nvidia.com: move comment, per David]
Link: https://lkml.kernel.org/r/5C9FA053-A4C6-4615-BE05-74E47A6462B3@nvidia.com
Link: https://lkml.kernel.org/r/20260302203159.3208341-1-ziy@nvidia.com
Fixes: 00527733d0dc ("mm/huge_memory: add two new (not yet used) functions for folio_split()")
Signed-off-by: Zi Yan <ziy@nvidia.com>
Reported-by: Bas van Dijk <bas@dfinity.org>
Closes: https://lore.kernel.org/all/CAKNNEtw5_kZomhkugedKMPOG-sxs5Q5OLumWJdiWXv+C9Yct0w@mail.gmail.com/
Tested-by: Lance Yang <lance.yang@linux.dev>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Nico Pache <npache@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
In the trylock path of refill_obj_stock(), mod_objcg_mlstate() should use
the real alloc/free bytes (i.e., nr_acct) for accounting, rather than
nr_bytes.
The user-visible impact is that the NR_SLAB_RECLAIMABLE_B and
NR_SLAB_UNRECLAIMABLE_B stats can end up being incorrect.
For example, if a user allocates a 6144-byte object, then before this
fix efill_obj_stock() calls mod_objcg_mlstate(..., nr_bytes=2048), even
though it should account for 6144 bytes (i.e., nr_acct).
When the user later frees the same object with kfree(),
refill_obj_stock() calls mod_objcg_mlstate(..., nr_bytes=6144). This
ends up adding 6144 to the stats, but it should be applying -6144
(i.e., nr_acct) since the object is being freed.
Link: https://lkml.kernel.org/r/20260226115145.62903-1-hao.li@linux.dev
Fixes: 200577f69f29 ("memcg: objcg stock trylock without irq disabling")
Signed-off-by: Hao Li <hao.li@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Vlastimil Babka <vbabka@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Architecture like powerpc, checks for pfn_valid() in their virt_to_phys()
implementation (when CONFIG_DEBUG_VIRTUAL is enabled) [1]. Commit
d49004c5f0c1 "arch, mm: consolidate initialization of nodes, zones and
memory map" changed the order of initialization between
hugetlb_bootmem_alloc() and free_area_init(). This means, pfn_valid() can
now return false in alloc_bootmem() path, since sparse_init() is not yet
done.
Since, alloc_bootmem() uses memblock_alloc(.., MEMBLOCK_ALLOC_ACCESSIBLE),
this means these allocations are always going to happen below high_memory,
where __pa() should return valid physical addresses. Hence this patch
converts the two callers of virt_to_phys() in alloc_bootmem() path to
__pa() to avoid this bootup warning:
------------[ cut here ]------------
WARNING: arch/powerpc/include/asm/io.h:879 at virt_to_phys+0x44/0x1b8, CPU#0: swapper/0
Modules linked in:
<...>
NIP [c000000000601584] virt_to_phys+0x44/0x1b8
LR [c000000004075de4] alloc_bootmem+0x144/0x1a8
Call Trace:
[c000000004d1fb50] [c000000004075dd4] alloc_bootmem+0x134/0x1a8
[c000000004d1fba0] [c000000004075fac] __alloc_bootmem_huge_page+0x164/0x230
[c000000004d1fbe0] [c000000004030bc4] alloc_bootmem_huge_page+0x44/0x138
[c000000004d1fc10] [c000000004076e48] hugetlb_hstate_alloc_pages+0x350/0x5ac
[c000000004d1fd30] [c0000000040782f0] hugetlb_bootmem_alloc+0x15c/0x19c
[c000000004d1fd70] [c00000000406d7b4] mm_core_init_early+0x7c/0xdf4
[c000000004d1ff30] [c000000004011d84] start_kernel+0xac/0xc58
[c000000004d1ffe0] [c00000000000e99c] start_here_common+0x1c/0x20
[1]: https://lore.kernel.org/linuxppc-dev/87tsv5h544.ritesh.list@gmail.com/
Link: https://lkml.kernel.org/r/b4a7d2c6c4c1dd81dddc904fc21f01303290a4b8.1772107852.git.riteshh@linux.ibm.com
Fixes: d49004c5f0c1 ("arch, mm: consolidate initialization of nodes, zones and memory map")
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
When CONFIG_DEBUG_VM is not set, VM_WARN_ON is a NOP. Putting any
statement with side effect inside it is incorrect. Collect all
!put_page_testzero() results and check the sum using WARN instead after
the loop. It restores the same check in free_contig_range() before commit
e0c1326779cc ("mm: page_alloc: add alloc_contig_frozen_{range,pages}()"),
the commit prior to the Fixes one.
Link: https://lkml.kernel.org/r/20260225031231.2352011-1-ziy@nvidia.com
Fixes: 9bda131c6093 ("mm: cma: add cma_alloc_frozen{_compound}()")
Signed-off-by: Zi Yan <ziy@nvidia.com>
Reported-by: Ron Economos <re@w6rz.net>
Closes: https://lore.kernel.org/all/1b17c38f-30d3-4bb4-a7e1-e74b19ada885@w6rz.net/
Suggested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Debugged-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Tested-by: Ron Economos <re@w6rz.net>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
damos_walk() sets ctx->walk_control to the caller-provided control
structure before checking whether the context is running. If the context
is inactive (damon_is_running() returns false), the function returns
-EINVAL without clearing ctx->walk_control. This leaves a dangling
pointer to a stack-allocated structure that will be freed when the caller
returns.
This is structurally identical to the bug fixed in commit f9132fbc2e83
("mm/damon/core: remove call_control in inactive contexts") for
damon_call(), which had the same pattern of linking a control object and
returning an error without unlinking it.
The dangling walk_control pointer can cause:
1. Use-after-free if the context is later started and kdamond
dereferences ctx->walk_control (e.g., in damos_walk_cancel()
which writes to control->canceled and calls complete())
2. Permanent -EBUSY from subsequent damos_walk() calls, since the
stale pointer is non-NULL
Nonetheless, the real user impact is quite restrictive. The
use-after-free is impossible because there is no damos_walk() callers who
starts the context later. The permanent -EBUSY can actually confuse
users, as DAMON is not running. But the symptom is kept only while the
context is turned off. Turning it on again will make DAMON internally
uses a newly generated damon_ctx object that doesn't have the invalid
damos_walk_control pointer, so everything will work fine again.
Fix this by clearing ctx->walk_control under walk_control_lock before
returning -EINVAL, mirroring the fix pattern from f9132fbc2e83.
Link: https://lkml.kernel.org/r/20260224011102.56033-1-sj@kernel.org
Fixes: bf0eaba0ff9c ("mm/damon/core: implement damos_walk()")
Reported-by: Raul Pazemecxas De Andrade <raul_pazemecxas@hotmail.com>
Closes: https://lore.kernel.org/CPUPR80MB8171025468965E583EF2490F956CA@CPUPR80MB8171.lamprd80.prod.outlook.com
Signed-off-by: Raul Pazemecxas De Andrade <raul_pazemecxas@hotmail.com>
Signed-off-by: SeongJae Park <sj@kernel.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> [6.14+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
A dirty folio is one which has been written to. A clean folio is its
opposite. Since a clean folio has no user data, it can be freed under
memory pressure.
memfd preservation with LUO saves the flag at preserve(). This is
problematic. The folio might get dirtied later. Saving it at freeze()
also doesn't work, since the dirty bit from PTE is normally synced at
unmap and there might still be mappings of the file at freeze().
To see why this is a problem, say a folio is clean at preserve, but gets
dirtied later. The serialized state of the folio will mark it as clean.
After retrieve, the next kernel will see the folio as clean and might try
to reclaim it under memory pressure. This will result in losing user
data.
Mark all folios of the file as dirty, and always set the
MEMFD_LUO_FOLIO_DIRTY flag. This comes with the side effect of making all
clean folios un-reclaimable. This is a cost that has to be paid for
participants of live update. It is not expected to be a common use case
to preserve a lot of clean folios anyway.
Since the value of pfolio->flags is a constant now, drop the flags
variable and set it directly.
Link: https://lkml.kernel.org/r/20260223173931.2221759-3-pratyush@kernel.org
Fixes: b3749f174d68 ("mm: memfd_luo: allow preserving memfd")
Signed-off-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Patch series "mm: memfd_luo: fixes for folio flag preservation".
This series contains a couple fixes for flag preservation for memfd live
update.
The first patch fixes memfd preservation when fallocate() was used to
pre-allocate some pages. For these memfds, all the writes to fallocated
pages touched after preserve were lost.
The second patch fixes dirty flag tracking. If the dirty flag is not
tracked correctly, the next kernel might incorrectly reclaim some folios
under memory pressure, losing user data. This is a theoretical bug that I
observed when reading the code, and haven't been able to reproduce it.
This patch (of 2):
When a folio is added to a shmem file via fallocate, it is not zeroed on
allocation. This is done as a performance optimization since it is
possible the folio will never end up being used at all. When the folio is
used, shmem checks for the uptodate flag, and if absent, zeroes the folio
(and sets the flag) before returning to user.
With LUO, the flags of each folio are saved at preserve time. It is
possible to have a memfd with some folios fallocated but not uptodate.
For those, the uptodate flag doesn't get saved. The folios might later
end up being used and become uptodate. They would get passed to the next
kernel via KHO correctly since they did get preserved. But they won't
have the MEMFD_LUO_FOLIO_UPTODATE flag.
This means that when the memfd is retrieved, the folios will be added to
the shmem file without the uptodate flag. They will be zeroed before
first use, losing the data in those folios.
Since we take a big performance hit in allocating, zeroing, and pinning
all folios at prepare time anyway, take some more and zero all
non-uptodate ones too.
Later when there is a stronger need to make prepare faster, this can be
optimized.
To avoid racing with another uptodate operation, take the folio lock.
Link: https://lkml.kernel.org/r/20260223173931.2221759-2-pratyush@kernel.org
Fixes: b3749f174d68 ("mm: memfd_luo: allow preserving memfd")
Signed-off-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Commit 7a8e71bc619d ("mm/slab: use stride to access slabobj_ext")
defined the type of slab->stride as unsigned short, because the author
initially planned to store stride within the lower 16 bits of the
page_type field, but later stored it in unused bits in the counters
field instead.
However, the idea of having only 2-byte stride turned out to be a
serious mistake. On systems with 64k pages, order-1 pages are 128k,
which is larger than USHRT_MAX. It triggers a debug warning because
s->size is 128k while stride, truncated to 2 bytes, becomes zero:
------------[ cut here ]------------
Warning! stride (0) != s->size (131072)
WARNING: mm/slub.c:2231 at alloc_slab_obj_exts_early.constprop.0+0x524/0x534, CPU#6: systemd-sysctl/307
Modules linked in:
CPU: 6 UID: 0 PID: 307 Comm: systemd-sysctl Not tainted 7.0.0-rc1+ #6 PREEMPTLAZY
Hardware name: IBM,9009-22A POWER9 (architected) 0x4e0202 0xf000005 of:IBM,FW950.E0 (VL950_179) hv:phyp pSeries
NIP: c0000000008a9ac0 LR: c0000000008a9abc CTR: 0000000000000000
REGS: c0000000141f7390 TRAP: 0700 Not tainted (7.0.0-rc1+)
MSR: 8000000000029033 <SF,EE,ME,IR,DR,RI,LE> CR: 28004400 XER: 00000005
CFAR: c000000000279318 IRQMASK: 0
GPR00: c0000000008a9abc c0000000141f7630 c00000000252a300 c00000001427b200
GPR04: 0000000000000004 0000000000000000 c000000000278fd0 0000000000000000
GPR08: fffffffffffe0000 0000000000000000 0000000000000000 0000000022004400
GPR12: c000000000f644b0 c000000017ff8f00 0000000000000000 0000000000000000
GPR16: 0000000000000000 c0000000141f7aa0 0000000000000000 c0000000141f7a88
GPR20: 0000000000000000 0000000000400cc0 ffffffffffffffff c00000001427b180
GPR24: 0000000000000004 00000000000c0cc0 c000000004e89a20 c00000005de90011
GPR28: 0000000000010010 c00000005df00000 c000000006017f80 c00c000000177a00
NIP [c0000000008a9ac0] alloc_slab_obj_exts_early.constprop.0+0x524/0x534
LR [c0000000008a9abc] alloc_slab_obj_exts_early.constprop.0+0x520/0x534
Call Trace:
[c0000000141f7630] [c0000000008a9abc] alloc_slab_obj_exts_early.constprop.0+0x520/0x534 (unreliable)
[c0000000141f76c0] [c0000000008aafbc] allocate_slab+0x154/0x94c
[c0000000141f7760] [c0000000008b41c0] refill_objects+0x124/0x16c
[c0000000141f77c0] [c0000000008b4be0] __pcs_replace_empty_main+0x2b0/0x444
[c0000000141f7810] [c0000000008b9600] __kvmalloc_node_noprof+0x840/0x914
[c0000000141f7900] [c000000000a3dd40] seq_read_iter+0x60c/0xb00
[c0000000141f7a10] [c000000000b36b24] proc_reg_read_iter+0x154/0x1fc
[c0000000141f7a50] [c0000000009cee7c] vfs_read+0x39c/0x4e4
[c0000000141f7b30] [c0000000009d0214] ksys_read+0x9c/0x180
[c0000000141f7b90] [c00000000003a8d0] system_call_exception+0x1e0/0x4b0
[c0000000141f7e50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec
This leads to slab_obj_ext() returning the first slabobj_ext or all
objects and confuses the reference counting of object cgroups [1] and
memory (un)charging for memory cgroups [2].
Fortunately, the counters field has 32 unused bits instead of 16
on 64-bit CPUs, which is wide enough to hold any value of s->size.
Change the type to unsigned int.
Reported-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Closes: https://lore.kernel.org/lkml/ca241daa-e7e7-4604-a48d-de91ec9184a5@linux.ibm.com [1]
Closes: https://lore.kernel.org/all/ddff7c7d-c0c3-4780-808f-9a83268bbf0c@linux.ibm.com [2]
Fixes: 7a8e71bc619d ("mm/slab: use stride to access slabobj_ext")
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Link: https://patch.msgid.link/20260303135722.2680521-1-harry.yoo@oracle.com
Reviewed-by: Hao Li <hao.li@linux.dev>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
|
|
Ming Lei reported [1] a regression in the ublk null target benchmark due
to sheaves. The profile shows that the alloc_from_pcs() fastpath fails
and allocations fall back to ___slab_alloc(). It also shows the
allocations happen through mempool_alloc().
The strategy of mempool_alloc() is to call the underlying allocator
(here slab) without __GFP_DIRECT_RECLAIM first. This does not play well
with __pcs_replace_empty_main() checking for gfpflags_allow_blocking()
to decide if it should refill an empty sheaf or fallback to the
slowpath, so we end up falling back.
We could change the mempool strategy but there might be other paths
doing the same ting. So instead allow sheaf refill when blocking is not
allowed, changing the condition to gfpflags_allow_spinning(). The
original condition was unnecessarily restrictive.
Note this doesn't fully resolve the regression [1] as another component
of that are memoryless nodes, which is to be addressed separately.
Reported-by: Ming Lei <ming.lei@redhat.com>
Fixes: e47c897a2949 ("slab: add sheaves to most caches")
Link: https://lore.kernel.org/all/aZ0SbIqaIkwoW2mB@fedora/ [1]
Link: https://patch.msgid.link/20260302095536.34062-2-vbabka@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
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If hmm_range_fault() fails a folio_trylock() in do_swap_page,
trying to acquire the lock of a device-private folio for migration,
to ram, the function will spin until it succeeds grabbing the lock.
However, if the process holding the lock is depending on a work
item to be completed, which is scheduled on the same CPU as the
spinning hmm_range_fault(), that work item might be starved and
we end up in a livelock / starvation situation which is never
resolved.
This can happen, for example if the process holding the
device-private folio lock is stuck in
migrate_device_unmap()->lru_add_drain_all()
sinc lru_add_drain_all() requires a short work-item
to be run on all online cpus to complete.
A prerequisite for this to happen is:
a) Both zone device and system memory folios are considered in
migrate_device_unmap(), so that there is a reason to call
lru_add_drain_all() for a system memory folio while a
folio lock is held on a zone device folio.
b) The zone device folio has an initial mapcount > 1 which causes
at least one migration PTE entry insertion to be deferred to
try_to_migrate(), which can happen after the call to
lru_add_drain_all().
c) No or voluntary only preemption.
This all seems pretty unlikely to happen, but indeed is hit by
the "xe_exec_system_allocator" igt test.
Resolve this by waiting for the folio to be unlocked if the
folio_trylock() fails in do_swap_page().
Rename migration_entry_wait_on_locked() to
softleaf_entry_wait_unlock() and update its documentation to
indicate the new use-case.
Future code improvements might consider moving
the lru_add_drain_all() call in migrate_device_unmap() to be
called *after* all pages have migration entries inserted.
That would eliminate also b) above.
v2:
- Instead of a cond_resched() in hmm_range_fault(),
eliminate the problem by waiting for the folio to be unlocked
in do_swap_page() (Alistair Popple, Andrew Morton)
v3:
- Add a stub migration_entry_wait_on_locked() for the
!CONFIG_MIGRATION case. (Kernel Test Robot)
v4:
- Rename migrate_entry_wait_on_locked() to
softleaf_entry_wait_on_locked() and update docs (Alistair Popple)
v5:
- Add a WARN_ON_ONCE() for the !CONFIG_MIGRATION
version of softleaf_entry_wait_on_locked().
- Modify wording around function names in the commit message
(Andrew Morton)
Suggested-by: Alistair Popple <apopple@nvidia.com>
Fixes: 1afaeb8293c9 ("mm/migrate: Trylock device page in do_swap_page")
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: linux-mm@kvack.org
Cc: <dri-devel@lists.freedesktop.org>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: <stable@vger.kernel.org> # v6.15+
Reviewed-by: John Hubbard <jhubbard@nvidia.com> #v3
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Link: https://patch.msgid.link/20260210115653.92413-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit a69d1ab971a624c6f112cea61536569d579c3215)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
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sheaf_flush_main() can be called from __pcs_replace_full_main() where
it's fine if the trylock fails, and pcs_flush_all() where it's not
expected to and for some flush callers (when destroying the cache or
memory hotremove) it would be actually a problem if it failed and left
the main sheaf not flushed. The flush callers can however safely use
local_lock() instead of trylock.
The trylock failure should not happen in practice on !PREEMPT_RT, but
can happen on PREEMPT_RT. The impact is limited in practice because when
a trylock fails in the kmem_cache_destroy() path, it means someone is
using the cache while destroying it, which is a bug on its own. The memory
hotremove path is unlikely to be employed in a production RT config, but
it's possible.
To fix this, split the function into sheaf_flush_main() (using
local_lock()) and sheaf_try_flush_main() (using local_trylock()) where
both call __sheaf_flush_main_batch() to flush a single batch of objects.
This will also allow lockdep to verify our context assumptions.
The problem was raised in an off-list question by Marcelo.
Fixes: 2d517aa09bbc ("slab: add opt-in caching layer of percpu sheaves")
Cc: stable@vger.kernel.org
Reported-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Hao Li <hao.li@linux.dev>
Link: https://patch.msgid.link/20260211-b4-sheaf-flush-v1-1-4e7f492f0055@suse.cz
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab fixes from Vlastimil Babka:
- Fix for spurious page allocation warnings on sheaf refill (Harry Yoo)
- Fix for CONFIG_MEM_ALLOC_PROFILING_DEBUG warnings (Suren
Baghdasaryan)
- Fix for kernel-doc warning on ksize() (Sanjay Chitroda)
- Fix to avoid setting slab->stride later than on slab allocation.
Doesn't yet fix the reports from powerpc; debugging is making
progress (Harry Yoo)
* tag 'slab-for-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
mm/slab: initialize slab->stride early to avoid memory ordering issues
mm/slub: drop duplicate kernel-doc for ksize()
mm/slab: mark alloc tags empty for sheaves allocated with __GFP_NO_OBJ_EXT
mm/slab: pass __GFP_NOWARN to refill_sheaf() if fallback is available
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When alloc_slab_obj_exts() is called later (instead of during slab
allocation and initialization), slab->stride and slab->obj_exts are
updated after the slab is already accessible by multiple CPUs.
The current implementation does not enforce memory ordering between
slab->stride and slab->obj_exts. For correctness, slab->stride must be
visible before slab->obj_exts. Otherwise, concurrent readers may observe
slab->obj_exts as non-zero while stride is still stale.
With stale slab->stride, slab_obj_ext() could return the wrong obj_ext.
This could cause two problems:
- obj_cgroup_put() is called on the wrong objcg, leading to
a use-after-free due to incorrect reference counting [1] by
decrementing the reference count more than it was incremented.
- refill_obj_stock() is called on the wrong objcg, leading to
a page_counter overflow [2] by uncharging more memory than charged.
Fix this by unconditionally initializing slab->stride in
alloc_slab_obj_exts_early(), before the need_slab_obj_exts() check.
In the case of SLAB_OBJ_EXT_IN_OBJ, it is overridden in the function.
This ensures updates to slab->stride become visible before the slab
can be accessed by other CPUs via the per-node partial slab list
(protected by spinlock with acquire/release semantics).
Thanks to Shakeel Butt for pointing out this issue [3].
[vbabka@kernel.org: the bug reports [1] and [2] are not yet fully fixed,
with investigation ongoing, but it is nevertheless a step in the right
direction to only set stride once after allocating the slab and not
change it later ]
Fixes: 7a8e71bc619d ("mm/slab: use stride to access slabobj_ext")
Reported-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Link: https://lore.kernel.org/lkml/ca241daa-e7e7-4604-a48d-de91ec9184a5@linux.ibm.com [1]
Link: https://lore.kernel.org/all/ddff7c7d-c0c3-4780-808f-9a83268bbf0c@linux.ibm.com [2]
Link: https://lore.kernel.org/linux-mm/aZu9G9mVIVzSm6Ft@hyeyoo [3]
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
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alloc_empty_sheaf() allocates sheaves from SLAB_KMALLOC caches using
__GFP_NO_OBJ_EXT to avoid recursion, however it does not mark their
allocation tags empty before freeing, which results in a warning when
CONFIG_MEM_ALLOC_PROFILING_DEBUG is set. Fix this by marking allocation
tags for such sheaves as empty.
The problem was technically introduced in commit 4c0a17e28340 but only
becomes possible to hit with commit 913ffd3a1bf5.
Fixes: 4c0a17e28340 ("slab: prevent recursive kmalloc() in alloc_empty_sheaf()")
Fixes: 913ffd3a1bf5 ("slab: handle kmalloc sheaves bootstrap")
Reported-by: David Wang <00107082@163.com>
Closes: https://lore.kernel.org/all/20260223155128.3849-1-00107082@163.com/
Analyzed-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Tested-by: Harry Yoo <harry.yoo@oracle.com>
Tested-by: David Wang <00107082@163.com>
Link: https://patch.msgid.link/20260225163407.2218712-1-surenb@google.com
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
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When refill_sheaf() is called, failing to refill the sheaf doesn't
necessarily mean the allocation will fail because a fallback path
might be available and serve the allocation request.
Suppress spurious warnings by passing __GFP_NOWARN along with
__GFP_NOMEMALLOC whenever a fallback path is available.
When the caller is alloc_full_sheaf() or __pcs_replace_empty_main(),
the kernel always falls back to the slowpath (__slab_alloc_node()).
For __prefill_sheaf_pfmemalloc(), the fallback path is available
only when gfp_pfmemalloc_allowed() returns true.
Reported-and-tested-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Closes: https://lore.kernel.org/linux-mm/aZt2-oS9lkmwT7Ch@debian.local
Fixes: 1ce20c28eafd ("slab: handle pfmemalloc slabs properly with sheaves")
Link: https://lore.kernel.org/linux-mm/aZwSreGj9-HHdD-j@hyeyoo
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Link: https://patch.msgid.link/20260223133322.16705-1-harry.yoo@oracle.com
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
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Commit d49004c5f0c1 ("arch, mm: consolidate initialization of nodes, zones
and memory map") moved free_area_init() from setup_arch() to
mm_core_init_early(), which runs after setup_arch() returns.
This changed the ordering relative to init_cpu_to_node() on x86. Before
the commit, free_area_init() ran during paging_init() (called from
setup_arch()) *before* init_cpu_to_node(). After the commit, it runs
*after* init_cpu_to_node().
On machines with memoryless NUMA nodes (e.g., node 0 has CPUs but no
memory), this causes a NULL pointer dereference:
1. numa_register_nodes() skips memoryless nodes: no alloc_node_data()
and no node_set_online() for them.
2. init_cpu_to_node() sets memoryless nodes online (they have CPUs)
but does not allocate NODE_DATA.
3. free_area_init() checks "if (!node_online(nid))" to decide whether
to call alloc_offline_node_data(). Since the memoryless node is now
online, the allocation is skipped, leaving NODE_DATA(nid) == NULL.
4. The immediate "pgdat = NODE_DATA(nid)" dereferences NULL.
The crash happens before console_init(), so no output is visible without
earlyprintk. With earlyprintk enabled, the following panic is observed:
BUG: unable to handle page fault for address: 000000000002a1e0
Oops: Oops: 0000 [#1] SMP NOPTI
RIP: 0010:free_area_init_node+0x3a/0x540
Call Trace:
<TASK>
free_area_init+0x331/0x4e0
start_kernel+0x69/0x4a0
x86_64_start_reservations+0x24/0x30
x86_64_start_kernel+0x125/0x130
common_startup_64+0x13e/0x148
</TASK>
Kernel panic - not syncing: Attempted to kill the idle task!
Fix this by checking "if (!NODE_DATA(nid))" instead of "if
(!node_online(nid))". This directly tests whether the per-node data
structure needs to be allocated, regardless of the node's online status.
This change is also safe for non-x86 architectures as they all allocate
NODE_DATA for every node including memoryless ones, so the check simply
evaluates to false with no change in behavior.
Link: https://lkml.kernel.org/r/20260222115702.3659-1-ming.lei@redhat.com
Fixes: d49004c5f0c1 ("arch, mm: consolidate initialization of nodes, zones and memory map")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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When KASAN hardware tags are enabled, re-enabling KFENCE late (via
/sys/module/kfence/parameters/sample_interval) causes KASAN faults.
This happens because the KFENCE pool and metadata are allocated via the
page allocator, which tags the memory, while KFENCE continues to access it
using untagged pointers during initialization.
Use __GFP_SKIP_KASAN for late KFENCE pool and metadata allocations to
ensure the memory remains untagged, consistent with early allocations from
memblock. To support this, add __GFP_SKIP_KASAN to the allowlist in
__alloc_contig_verify_gfp_mask().
Link: https://lkml.kernel.org/r/20260220144940.2779209-1-glider@google.com
Fixes: 0ce20dd84089 ("mm: add Kernel Electric-Fence infrastructure")
Signed-off-by: Alexander Potapenko <glider@google.com>
Suggested-by: Ernesto Martinez Garcia <ernesto.martinezgarcia@tugraz.at>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Kees Cook <kees@kernel.org>
Cc: Marco Elver <elver@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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DAMON core uses min_region_sz parameter value as the DAMON region
alignment. The alignment is made using ALIGN() and ALIGN_DOWN(), which
support only the power of two alignments. But DAMON core API callers can
set min_region_sz to an arbitrary number. Users can also set it
indirectly, using addr_unit.
When the alignment is not properly set, DAMON behavior becomes difficult
to expect and understand, makes it effectively broken. It doesn't cause a
kernel crash-like significant issue, though.
Fix the issue by disallowing min_region_sz input that is not a power of
two. Add the check to damon_commit_ctx(), as all DAMON API callers who
set min_region_sz uses the function.
This can be a sort of behavioral change, but it does not break users, for
the following reasons. As the symptom is making DAMON effectively broken,
it is not reasonable to believe there are real use cases of non-power of
two min_region_sz. There is no known use case or issue reports from the
setup, either.
In future, if we find real use cases of non-power of two alignments and we
can support it with low enough overhead, we can consider moving the
restriction. But, for now, simply disallowing the corner case should be
good enough as a hot fix.
Link: https://lkml.kernel.org/r/20260214214124.87689-1-sj@kernel.org
Fixes: d8f867fa0825 ("mm/damon: add damon_ctx->min_sz_region")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Quanmin Yan <yanquanmin1@huawei.com>
Cc: <stable@vger.kernel.org> [6.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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LUO keeps track of successful retrieve attempts on a LUO file. It does so
to avoid multiple retrievals of the same file. Multiple retrievals cause
problems because once the file is retrieved, the serialized data
structures are likely freed and the file is likely in a very different
state from what the code expects.
The retrieve boolean in struct luo_file keeps track of this, and is passed
to the finish callback so it knows what work was already done and what it
has left to do.
All this works well when retrieve succeeds. When it fails,
luo_retrieve_file() returns the error immediately, without ever storing
anywhere that a retrieve was attempted or what its error code was. This
results in an errored LIVEUPDATE_SESSION_RETRIEVE_FD ioctl to userspace,
but nothing prevents it from trying this again.
The retry is problematic for much of the same reasons listed above. The
file is likely in a very different state than what the retrieve logic
normally expects, and it might even have freed some serialization data
structures. Attempting to access them or free them again is going to
break things.
For example, if memfd managed to restore 8 of its 10 folios, but fails on
the 9th, a subsequent retrieve attempt will try to call
kho_restore_folio() on the first folio again, and that will fail with a
warning since it is an invalid operation.
Apart from the retry, finish() also breaks. Since on failure the
retrieved bool in luo_file is never touched, the finish() call on session
close will tell the file handler that retrieve was never attempted, and it
will try to access or free the data structures that might not exist, much
in the same way as the retry attempt.
There is no sane way of attempting the retrieve again. Remember the error
retrieve returned and directly return it on a retry. Also pass this
status code to finish() so it can make the right decision on the work it
needs to do.
This is done by changing the bool to an integer. A value of 0 means
retrieve was never attempted, a positive value means it succeeded, and a
negative value means it failed and the error code is the value.
Link: https://lkml.kernel.org/r/20260216132221.987987-1-pratyush@kernel.org
Fixes: 7c722a7f44e0 ("liveupdate: luo_file: implement file systems callbacks")
Signed-off-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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file_thp_enabled() incorrectly allows THP for files on anonymous inodes
(e.g. guest_memfd and secretmem). These files are created via
alloc_file_pseudo(), which does not call get_write_access() and leaves
inode->i_writecount at 0. Combined with S_ISREG(inode->i_mode) being
true, they appear as read-only regular files when
CONFIG_READ_ONLY_THP_FOR_FS is enabled, making them eligible for THP
collapse.
Anonymous inodes can never pass the inode_is_open_for_write() check
since their i_writecount is never incremented through the normal VFS
open path. The right thing to do is to exclude them from THP eligibility
altogether, since CONFIG_READ_ONLY_THP_FOR_FS was designed for real
filesystem files (e.g. shared libraries), not for pseudo-filesystem
inodes.
For guest_memfd, this allows khugepaged and MADV_COLLAPSE to create
large folios in the page cache via the collapse path, but the
guest_memfd fault handler does not support large folios. This triggers
WARN_ON_ONCE(folio_test_large(folio)) in kvm_gmem_fault_user_mapping().
For secretmem, collapse_file() tries to copy page contents through the
direct map, but secretmem pages are removed from the direct map. This
can result in a kernel crash:
BUG: unable to handle page fault for address: ffff88810284d000
RIP: 0010:memcpy_orig+0x16/0x130
Call Trace:
collapse_file
hpage_collapse_scan_file
madvise_collapse
Secretmem is not affected by the crash on upstream as the memory failure
recovery handles the failed copy gracefully, but it still triggers
confusing false memory failure reports:
Memory failure: 0x106d96f: recovery action for clean unevictable
LRU page: Recovered
Check IS_ANON_FILE(inode) in file_thp_enabled() to deny THP for all
anonymous inode files.
Link: https://syzkaller.appspot.com/bug?extid=33a04338019ac7e43a44
Link: https://lore.kernel.org/linux-mm/CAEvNRgHegcz3ro35ixkDw39ES8=U6rs6S7iP0gkR9enr7HoGtA@mail.gmail.com
Link: https://lkml.kernel.org/r/20260214001535.435626-1-kartikey406@gmail.com
Fixes: 7fbb5e188248 ("mm: remove VM_EXEC requirement for THP eligibility")
Signed-off-by: Deepanshu Kartikey <Kartikey406@gmail.com>
Reported-by: syzbot+33a04338019ac7e43a44@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=33a04338019ac7e43a44
Tested-by: syzbot+33a04338019ac7e43a44@syzkaller.appspotmail.com
Tested-by: Lance Yang <lance.yang@linux.dev>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Barry Song <baohua@kernel.org>
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Tested-by: Ackerley Tng <ackerleytng@google.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Fangrui Song <i@maskray.me>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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KFENCE does not currently support KASAN hardware tags. As a result, the
two features are incompatible when enabled simultaneously.
Given that MTE provides deterministic protection and KFENCE is a
sampling-based debugging tool, prioritize the stronger hardware
protections. Disable KFENCE initialization and free the pre-allocated
pool if KASAN hardware tags are detected to ensure the system maintains
the security guarantees provided by MTE.
Link: https://lkml.kernel.org/r/20260213095410.1862978-1-glider@google.com
Fixes: 0ce20dd84089 ("mm: add Kernel Electric-Fence infrastructure")
Signed-off-by: Alexander Potapenko <glider@google.com>
Suggested-by: Marco Elver <elver@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ernesto Martinez Garcia <ernesto.martinezgarcia@tugraz.at>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Kees Cook <kees@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Conversion performed via this Coccinelle script:
// SPDX-License-Identifier: GPL-2.0-only
// Options: --include-headers-for-types --all-includes --include-headers --keep-comments
virtual patch
@gfp depends on patch && !(file in "tools") && !(file in "samples")@
identifier ALLOC = {kmalloc_obj,kmalloc_objs,kmalloc_flex,
kzalloc_obj,kzalloc_objs,kzalloc_flex,
kvmalloc_obj,kvmalloc_objs,kvmalloc_flex,
kvzalloc_obj,kvzalloc_objs,kvzalloc_flex};
@@
ALLOC(...
- , GFP_KERNEL
)
$ make coccicheck MODE=patch COCCI=gfp.cocci
Build and boot tested x86_64 with Fedora 42's GCC and Clang:
Linux version 6.19.0+ (user@host) (gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7), GNU ld version 2.44-12.fc42) #1 SMP PREEMPT_DYNAMIC 1970-01-01
Linux version 6.19.0+ (user@host) (clang version 20.1.8 (Fedora 20.1.8-4.fc42), LLD 20.1.8) #1 SMP PREEMPT_DYNAMIC 1970-01-01
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This converts some of the visually simpler cases that have been split
over multiple lines. I only did the ones that are easy to verify the
resulting diff by having just that final GFP_KERNEL argument on the next
line.
Somebody should probably do a proper coccinelle script for this, but for
me the trivial script actually resulted in an assertion failure in the
middle of the script. I probably had made it a bit _too_ trivial.
So after fighting that far a while I decided to just do some of the
syntactically simpler cases with variations of the previous 'sed'
scripts.
The more syntactically complex multi-line cases would mostly really want
whitespace cleanup anyway.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
