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23243 Commits
Author | SHA1 | Message | Date | |
---|---|---|---|---|
Linus Torvalds
|
a8cc743272 |
17 hotfixes. 9 are cc:stable. 13 are MM and 4 are non-MM.
The usual collection of singletons - please see the changelogs. -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZyfGDAAKCRDdBJ7gKXxA jr19AQD6bfDF/6L2Alq1QG26pgrgccEbKzDSzR6pBajwCbdrNQD/XPhiv3zRJfGf lgt0Qkqwe/ApBhVYUnL8y1CePv3EDgA= =W5W0 -----END PGP SIGNATURE----- Merge tag 'mm-hotfixes-stable-2024-11-03-10-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "17 hotfixes. 9 are cc:stable. 13 are MM and 4 are non-MM. The usual collection of singletons - please see the changelogs" * tag 'mm-hotfixes-stable-2024-11-03-10-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: mm: multi-gen LRU: use {ptep,pmdp}_clear_young_notify() mm: multi-gen LRU: remove MM_LEAF_OLD and MM_NONLEAF_TOTAL stats mm, mmap: limit THP alignment of anonymous mappings to PMD-aligned sizes mm: shrinker: avoid memleak in alloc_shrinker_info .mailmap: update e-mail address for Eugen Hristev vmscan,migrate: fix page count imbalance on node stats when demoting pages mailmap: update Jarkko's email addresses mm: allow set/clear page_type again nilfs2: fix potential deadlock with newly created symlinks Squashfs: fix variable overflow in squashfs_readpage_block kasan: remove vmalloc_percpu test tools/mm: -Werror fixes in page-types/slabinfo mm, swap: avoid over reclaim of full clusters mm: fix PSWPIN counter for large folios swap-in mm: avoid VM_BUG_ON when try to map an anon large folio to zero page. mm/codetag: fix null pointer check logic for ref and tag mm/gup: stop leaking pinned pages in low memory conditions |
||
Yu Zhao
|
1d4832becd |
mm: multi-gen LRU: use {ptep,pmdp}_clear_young_notify()
When the MM_WALK capability is enabled, memory that is mostly accessed by
a VM appears younger than it really is, therefore this memory will be less
likely to be evicted. Therefore, the presence of a running VM can
significantly increase swap-outs for non-VM memory, regressing the
performance for the rest of the system.
Fix this regression by always calling {ptep,pmdp}_clear_young_notify()
whenever we clear the young bits on PMDs/PTEs.
[jthoughton@google.com: fix link-time error]
Link: https://lkml.kernel.org/r/20241019012940.3656292-3-jthoughton@google.com
Fixes:
|
||
Yu Zhao
|
ddd6d8e975 |
mm: multi-gen LRU: remove MM_LEAF_OLD and MM_NONLEAF_TOTAL stats
Patch series "mm: multi-gen LRU: Have secondary MMUs participate in
MM_WALK".
Today, the MM_WALK capability causes MGLRU to clear the young bit from
PMDs and PTEs during the page table walk before eviction, but MGLRU does
not call the clear_young() MMU notifier in this case. By not calling this
notifier, the MM walk takes less time/CPU, but it causes pages that are
accessed mostly through KVM / secondary MMUs to appear younger than they
should be.
We do call the clear_young() notifier today, but only when attempting to
evict the page, so we end up clearing young/accessed information less
frequently for secondary MMUs than for mm PTEs, and therefore they appear
younger and are less likely to be evicted. Therefore, memory that is
*not* being accessed mostly by KVM will be evicted *more* frequently,
worsening performance.
ChromeOS observed a tab-open latency regression when enabling MGLRU with a
setup that involved running a VM:
Tab-open latency histogram (ms)
Version p50 mean p95 p99 max
base 1315 1198 2347 3454 10319
mglru 2559 1311 7399 12060 43758
fix 1119 926 2470 4211 6947
This series replaces the final non-selftest patchs from this series[1],
which introduced a similar change (and a new MMU notifier) with KVM
optimizations. I'll send a separate series (to Sean and Paolo) for the
KVM optimizations.
This series also makes proactive reclaim with MGLRU possible for KVM
memory. I have verified that this functions correctly with the selftest
from [1], but given that that test is a KVM selftest, I'll send it with
the rest of the KVM optimizations later. Andrew, let me know if you'd
like to take the test now anyway.
[1]: https://lore.kernel.org/linux-mm/20240926013506.860253-18-jthoughton@google.com/
This patch (of 2):
The removed stats, MM_LEAF_OLD and MM_NONLEAF_TOTAL, are not very helpful
and become more complicated to properly compute when adding
test/clear_young() notifiers in MGLRU's mm walk.
Link: https://lkml.kernel.org/r/20241019012940.3656292-1-jthoughton@google.com
Link: https://lkml.kernel.org/r/20241019012940.3656292-2-jthoughton@google.com
Fixes:
|
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Vlastimil Babka
|
d4148aeab4 |
mm, mmap: limit THP alignment of anonymous mappings to PMD-aligned sizes
Since commit |
||
Chen Ridong
|
15e8156713 |
mm: shrinker: avoid memleak in alloc_shrinker_info
A memleak was found as below:
unreferenced object 0xffff8881010d2a80 (size 32):
comm "mkdir", pid 1559, jiffies 4294932666
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 @...............
backtrace (crc 2e7ef6fa):
[<ffffffff81372754>] __kmalloc_node_noprof+0x394/0x470
[<ffffffff813024ab>] alloc_shrinker_info+0x7b/0x1a0
[<ffffffff813b526a>] mem_cgroup_css_online+0x11a/0x3b0
[<ffffffff81198dd9>] online_css+0x29/0xa0
[<ffffffff811a243d>] cgroup_apply_control_enable+0x20d/0x360
[<ffffffff811a5728>] cgroup_mkdir+0x168/0x5f0
[<ffffffff8148543e>] kernfs_iop_mkdir+0x5e/0x90
[<ffffffff813dbb24>] vfs_mkdir+0x144/0x220
[<ffffffff813e1c97>] do_mkdirat+0x87/0x130
[<ffffffff813e1de9>] __x64_sys_mkdir+0x49/0x70
[<ffffffff81f8c928>] do_syscall_64+0x68/0x140
[<ffffffff8200012f>] entry_SYSCALL_64_after_hwframe+0x76/0x7e
alloc_shrinker_info(), when shrinker_unit_alloc() returns an errer, the
info won't be freed. Just fix it.
Link: https://lkml.kernel.org/r/20241025060942.1049263-1-chenridong@huaweicloud.com
Fixes:
|
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Gregory Price
|
35e41024c4 |
vmscan,migrate: fix page count imbalance on node stats when demoting pages
When numa balancing is enabled with demotion, vmscan will call
migrate_pages when shrinking LRUs. migrate_pages will decrement the
the node's isolated page count, leading to an imbalanced count when
invoked from (MG)LRU code.
The result is dmesg output like such:
$ cat /proc/sys/vm/stat_refresh
[77383.088417] vmstat_refresh: nr_isolated_anon -103212
[77383.088417] vmstat_refresh: nr_isolated_file -899642
This negative value may impact compaction and reclaim throttling.
The following path produces the decrement:
shrink_folio_list
demote_folio_list
migrate_pages
migrate_pages_batch
migrate_folio_move
migrate_folio_done
mod_node_page_state(-ve) <- decrement
This path happens for SUCCESSFUL migrations, not failures. Typically
callers to migrate_pages are required to handle putback/accounting for
failures, but this is already handled in the shrink code.
When accounting for migrations, instead do not decrement the count when
the migration reason is MR_DEMOTION. As of v6.11, this demotion logic
is the only source of MR_DEMOTION.
Link: https://lkml.kernel.org/r/20241025141724.17927-1-gourry@gourry.net
Fixes:
|
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Andrey Konovalov
|
330d8df81f |
kasan: remove vmalloc_percpu test
Commit |
||
Kairui Song
|
5168a68eb7 |
mm, swap: avoid over reclaim of full clusters
When running low on usable slots, cluster allocator will try to reclaim
the full clusters aggressively to reclaim HAS_CACHE slots. This
guarantees that as long as there are any usable slots, HAS_CACHE or not,
the swap device will be usable and workload won't go OOM early.
Before the cluster allocator, swap allocator fails easily if device is
filled up with reclaimable HAS_CACHE slots. Which can be easily
reproduced with following simple program:
#include <stdio.h>
#include <string.h>
#include <linux/mman.h>
#include <sys/mman.h>
#define SIZE 8192UL * 1024UL * 1024UL
int main(int argc, char **argv) {
long tmp;
char *p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
memset(p, 0, SIZE);
madvise(p, SIZE, MADV_PAGEOUT);
for (unsigned long i = 0; i < SIZE; ++i)
tmp += p[i];
getchar(); /* Pause */
return 0;
}
Setup an 8G non ramdisk swap, the first run of the program will swapout 8G
ram successfully. But run same program again after the first run paused,
the second run can't swapout all 8G memory as now half of the swap device
is pinned by HAS_CACHE. There was a random scan in the old allocator that
may reclaim part of the HAS_CACHE by luck, but it's unreliable.
The new allocator's added reclaim of full clusters when device is low on
usable slots. But when multiple CPUs are seeing the device is low on
usable slots at the same time, they ran into a thundering herd problem.
This is an observable problem on large machine with mass parallel
workload, as full cluster reclaim is slower on large swap device and
higher number of CPUs will also make things worse.
Testing using a 128G ZRAM on a 48c96t system. When the swap device is
very close to full (eg. 124G / 128G), running build linux kernel with
make -j96 in a 1G memory cgroup will hung (not a softlockup though)
spinning in full cluster reclaim for about ~5min before go OOM.
To solve this, split the full reclaim into two parts:
- Instead of do a synchronous aggressively reclaim when device is low,
do only one aggressively reclaim when device is strictly full with a
kworker. This still ensures in worst case the device won't be unusable
because of HAS_CACHE slots.
- To avoid allocation (especially higher order) suffer from HAS_CACHE
filling up clusters and kworker not responsive enough, do one synchronous
scan every time the free list is drained, and only scan one cluster. This
is kind of similar to the random reclaim before, keeps the full clusters
rotated and has a minimal latency. This should provide a fair reclaim
strategy suitable for most workloads.
Link: https://lkml.kernel.org/r/20241022175512.10398-1-ryncsn@gmail.com
Fixes:
|
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Barry Song
|
b54e1bfecc |
mm: fix PSWPIN counter for large folios swap-in
Similar to PSWPOUT, we should count the number of base pages instead of
large folios.
Link: https://lkml.kernel.org/r/20241023210201.2798-1-21cnbao@gmail.com
Fixes:
|
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Zi Yan
|
e0fc203748 |
mm: avoid VM_BUG_ON when try to map an anon large folio to zero page.
An anonymous large folio can be split into non order-0 folios,
try_to_map_unused_to_zeropage() should not VM_BUG_ON compound pages but
just return false. This fixes the crash when splitting anonymous large
folios to non order-0 folios.
Link: https://lkml.kernel.org/r/20241023171236.1122535-1-ziy@nvidia.com
Fixes:
|
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John Hubbard
|
aa6f8b2593 |
mm/gup: stop leaking pinned pages in low memory conditions
If a driver tries to call any of the pin_user_pages*(FOLL_LONGTERM) family
of functions, and requests "too many" pages, then the call will
erroneously leave pages pinned. This is visible in user space as an
actual memory leak.
Repro is trivial: just make enough pin_user_pages(FOLL_LONGTERM) calls to
exhaust memory.
The root cause of the problem is this sequence, within
__gup_longterm_locked():
__get_user_pages_locked()
rc = check_and_migrate_movable_pages()
...which gets retried in a loop. The loop error handling is incomplete,
clearly due to a somewhat unusual and complicated tri-state error API.
But anyway, if -ENOMEM, or in fact, any unexpected error is returned from
check_and_migrate_movable_pages(), then __gup_longterm_locked() happily
returns the error, while leaving the pages pinned.
In the failed case, which is an app that requests (via a device driver)
30720000000 bytes to be pinned, and then exits, I see this:
$ grep foll /proc/vmstat
nr_foll_pin_acquired 7502048
nr_foll_pin_released 2048
And after applying this patch, it returns to balanced pins:
$ grep foll /proc/vmstat
nr_foll_pin_acquired 7502048
nr_foll_pin_released 7502048
Note that the child routine, check_and_migrate_movable_folios(), avoids
this problem, by unpinning any folios in the **folios argument, before
returning an error.
Fix this by making check_and_migrate_movable_pages() behave in exactly the
same way as check_and_migrate_movable_folios(): unpin all pages in
**pages, before returning an error.
Also, documentation was an aggravating factor, so:
1) Consolidate the documentation for these two routines, now that they
have identical external behavior.
2) Rewrite the consolidated documentation:
a) Clearly list the three return code cases, and what happens in
each case.
b) Mention that one of the cases unpins the pages or folios, before
returning an error code.
Link: https://lkml.kernel.org/r/20241018223411.310331-1-jhubbard@nvidia.com
Fixes:
|
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Linus Torvalds
|
7fbaacafbc |
slab fixes for 6.12-rc6
-----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEEe7vIQRWZI0iWSE3xu+CwddJFiJoFAmcgrxcACgkQu+CwddJF iJrq9ggAiZ/2c7p23s52LdVhT9GTyV5omVOh2kDztVx4w6RM3RbkhkLWdqt0XUag uf1TJe6kOvnCeHEFEEo3sqPj820XebxKDf0GGCdI6a9f4n30ipKH+vWSQ0iutKO/ dOBdArxr0FGOV5VZR9i3xQ6sUqZXXUbJdte0c0ovp6Q6HDHTeQeKNhOQ2fv33TG/ 7jBh5HVyhI6JE/+TOxrMaklH0IqYBb6z49wdbaN7XBvXVXlb5MtOZy109gfUHDwe tfktifyE45VtmF0WdHfxDbCnqyDSG1Jm3wsLDbMq+voJ1BQlUvIZ5Dv4kucYqffm VN5HkH6uQ09aoounBoU4g50UYeNpiQ== =xAw8 -----END PGP SIGNATURE----- Merge tag 'slab-for-6.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab Pull slab fixes from Vlastimil Babka: - Fix for a slub_kunit test warning with MEM_ALLOC_PROFILING_DEBUG (Pei Xiao) - Fix for a MTE-based KASAN BUG in krealloc() (Qun-Wei Lin) * tag 'slab-for-6.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: mm: krealloc: Fix MTE false alarm in __do_krealloc slub/kunit: fix a WARNING due to unwrapped __kmalloc_cache_noprof |
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Qun-Wei Lin
|
704573851b |
mm: krealloc: Fix MTE false alarm in __do_krealloc
This patch addresses an issue introduced by commit |
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Barry Song
|
01626a1823 |
mm: avoid unconditional one-tick sleep when swapcache_prepare fails
Commit |
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Kirill A. Shutemov
|
58a039e679 |
mm: split critical region in remap_file_pages() and invoke LSMs in between
Commit |
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Lorenzo Stoakes
|
c4d91e225f |
mm/vma: add expand-only VMA merge mode and optimise do_brk_flags()
Patch series "introduce VMA merge mode to improve brk() performance".
A ~5% performance regression was discovered on the
aim9.brk_test.ops_per_sec by the linux kernel test bot [0].
In the past to satisfy brk() performance we duplicated VMA expansion code
and special-cased do_brk_flags(). This is however horrid and undoes work
to abstract this logic, so in resolving the issue I have endeavoured to
avoid this.
Investigating further I was able to observe that the use of a
vma_iter_next_range() and vma_prev() pair, causing an unnecessary maple
tree walk. In addition there is work that we do that is simply
unnecessary for brk().
Therefore, add a special VMA merge mode VMG_FLAG_JUST_EXPAND to avoid
doing any of this - it assumes the VMA iterator is pointing at the
previous VMA and which skips logic that brk() does not require.
This mostly eliminates the performance regression reducing it to ~2% which
is in the realm of noise. In addition, the will-it-scale test brk2,
written to be more representative of real-world brk() usage, shows a
modest performance improvement - which gives me confidence that we are not
meaningfully regressing real workloads here.
This series includes a test asserting that the 'just expand' mode works as
expected.
With many thanks to Oliver Sang for helping with performance testing of
candidate patch sets!
[0]:https://lore.kernel.org/linux-mm/202409301043.629bea78-oliver.sang@intel.com
This patch (of 2):
We know in advance that do_brk_flags() wants only to perform a VMA
expansion (if the prior VMA is compatible), and that we assume no
mergeable VMA follows it.
These are the semantics of this function prior to the recent rewrite of
the VMA merging logic, however we are now doing more work than necessary -
positioning the VMA iterator at the prior VMA and performing tasks that
are not required.
Add a new field to the vmg struct to permit merge flags and add a new
merge flag VMG_FLAG_JUST_EXPAND which implies this behaviour, and have
do_brk_flags() use this.
This fixes a reported performance regression in a brk() benchmarking suite.
Link: https://lkml.kernel.org/r/cover.1729174352.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/4e65d4395e5841c5acf8470dbcb714016364fd39.1729174352.git.lorenzo.stoakes@oracle.com
Fixes:
|
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Nobuhiro Iwamatsu
|
d95fb348f0 |
mm: numa_clear_kernel_node_hotplug: Add NUMA_NO_NODE check for node id
The acquired memory blocks for reserved may include blocks outside of
memory management. In this case, the nid variable is set to NUMA_NO_NODE
(-1), so an error occurs in node_set(). This adds a check using
numa_valid_node() to numa_clear_kernel_node_hotplug() that skips
node_set() when nid is set to NUMA_NO_NODE.
Link: https://lkml.kernel.org/r/1729070461-13576-1-git-send-email-nobuhiro1.iwamatsu@toshiba.co.jp
Fixes:
|
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Jeongjun Park
|
d949d1d14f |
mm: shmem: fix data-race in shmem_getattr()
I got the following KCSAN report during syzbot testing:
==================================================================
BUG: KCSAN: data-race in generic_fillattr / inode_set_ctime_current
write to 0xffff888102eb3260 of 4 bytes by task 6565 on cpu 1:
inode_set_ctime_to_ts include/linux/fs.h:1638 [inline]
inode_set_ctime_current+0x169/0x1d0 fs/inode.c:2626
shmem_mknod+0x117/0x180 mm/shmem.c:3443
shmem_create+0x34/0x40 mm/shmem.c:3497
lookup_open fs/namei.c:3578 [inline]
open_last_lookups fs/namei.c:3647 [inline]
path_openat+0xdbc/0x1f00 fs/namei.c:3883
do_filp_open+0xf7/0x200 fs/namei.c:3913
do_sys_openat2+0xab/0x120 fs/open.c:1416
do_sys_open fs/open.c:1431 [inline]
__do_sys_openat fs/open.c:1447 [inline]
__se_sys_openat fs/open.c:1442 [inline]
__x64_sys_openat+0xf3/0x120 fs/open.c:1442
x64_sys_call+0x1025/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:258
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x54/0x120 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
read to 0xffff888102eb3260 of 4 bytes by task 3498 on cpu 0:
inode_get_ctime_nsec include/linux/fs.h:1623 [inline]
inode_get_ctime include/linux/fs.h:1629 [inline]
generic_fillattr+0x1dd/0x2f0 fs/stat.c:62
shmem_getattr+0x17b/0x200 mm/shmem.c:1157
vfs_getattr_nosec fs/stat.c:166 [inline]
vfs_getattr+0x19b/0x1e0 fs/stat.c:207
vfs_statx_path fs/stat.c:251 [inline]
vfs_statx+0x134/0x2f0 fs/stat.c:315
vfs_fstatat+0xec/0x110 fs/stat.c:341
__do_sys_newfstatat fs/stat.c:505 [inline]
__se_sys_newfstatat+0x58/0x260 fs/stat.c:499
__x64_sys_newfstatat+0x55/0x70 fs/stat.c:499
x64_sys_call+0x141f/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:263
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x54/0x120 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
value changed: 0x2755ae53 -> 0x27ee44d3
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3498 Comm: udevd Not tainted 6.11.0-rc6-syzkaller-00326-gd1f2d51b711a-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
==================================================================
When calling generic_fillattr(), if you don't hold read lock, data-race
will occur in inode member variables, which can cause unexpected
behavior.
Since there is no special protection when shmem_getattr() calls
generic_fillattr(), data-race occurs by functions such as shmem_unlink()
or shmem_mknod(). This can cause unexpected results, so commenting it out
is not enough.
Therefore, when calling generic_fillattr() from shmem_getattr(), it is
appropriate to protect the inode using inode_lock_shared() and
inode_unlock_shared() to prevent data-race.
Link: https://lkml.kernel.org/r/20240909123558.70229-1-aha310510@gmail.com
Fixes:
|
||
Jann Horn
|
14611508cb |
mm: mark mas allocation in vms_abort_munmap_vmas as __GFP_NOFAIL
vms_abort_munmap_vmas() is a recovery path where, on entry, some VMAs have
already been torn down halfway (in a way we can't undo) but are still
present in the maple tree.
At this point, we *must* remove the VMAs from the VMA tree, otherwise we
get UAF.
Because removing VMA tree nodes can require memory allocation, the
existing code has an error path which tries to handle this by reattaching
the VMAs; but that can't be done safely.
A nicer way to fix it would probably be to preallocate enough maple tree
nodes for the removal before the point of no return, or something like
that; but for now, fix it the easy and kinda ugly way, by marking this
allocation __GFP_NOFAIL.
Link: https://lkml.kernel.org/r/20241016-fix-munmap-abort-v1-1-601c94b2240d@google.com
Fixes:
|
||
Huang Ying
|
b7c5f9a1fb |
resource: remove dependency on SPARSEMEM from GET_FREE_REGION
We want to use the functions (get_free_mem_region()) configured via GET_FREE_REGION in resource kunit tests. However, GET_FREE_REGION depends on SPARSEMEM now. This makes resource kunit tests cannot be built on some architectures lacking SPARSEMEM, or causes config warning as follows, WARNING: unmet direct dependencies detected for GET_FREE_REGION Depends on [n]: SPARSEMEM [=n] Selected by [y]: - RESOURCE_KUNIT_TEST [=y] && RUNTIME_TESTING_MENU [=y] && KUNIT [=y] When get_free_mem_region() was introduced the only consumers were those looking to pass the address range to memremap_pages(). That address range needed to be mindful of the maximum addressable platform physical address which at the time only SPARSMEM defined via MAX_PHYSMEM_BITS. Given that memremap_pages() also depended on SPARSEMEM via ZONE_DEVICE, it was easier to just depend on that definition than invent a general MAX_PHYSMEM_BITS concept outside of SPARSEMEM. Turns out that decision was buggy and did not account for KASAN consumption of physical address space. That problem was resolved recently with commit |
||
Liam R. Howlett
|
79f3d123ca |
mm/mmap: fix race in mmap_region() with ftruncate()
Avoiding the zeroing of the vma tree in mmap_region() introduced a race
with truncate in the page table walk. To avoid any races, create a hole
in the rmap during the operation by clearing the pagetable entries earlier
under the mmap write lock and (critically) before the new vma is installed
into the vma tree. The result is that the old vma(s) are left in the vma
tree, but free_pgtables() removes them from the rmap and clears the ptes
while holding the necessary locks.
This change extends the fix required for hugetblfs and the call_mmap()
function by moving the cleanup higher in the function and running it
unconditionally.
Link: https://lkml.kernel.org/r/20241016013455.2241533-1-Liam.Howlett@oracle.com
Fixes:
|
||
Matt Fleming
|
281dd25c1a |
mm/page_alloc: let GFP_ATOMIC order-0 allocs access highatomic reserves
Under memory pressure it's possible for GFP_ATOMIC order-0 allocations to
fail even though free pages are available in the highatomic reserves.
GFP_ATOMIC allocations cannot trigger unreserve_highatomic_pageblock()
since it's only run from reclaim.
Given that such allocations will pass the watermarks in
__zone_watermark_unusable_free(), it makes sense to fallback to highatomic
reserves the same way that ALLOC_OOM can.
This fixes order-0 page allocation failures observed on Cloudflare's fleet
when handling network packets:
kswapd1: page allocation failure: order:0, mode:0x820(GFP_ATOMIC),
nodemask=(null),cpuset=/,mems_allowed=0-7
CPU: 10 PID: 696 Comm: kswapd1 Kdump: loaded Tainted: G O 6.6.43-CUSTOM #1
Hardware name: MACHINE
Call Trace:
<IRQ>
dump_stack_lvl+0x3c/0x50
warn_alloc+0x13a/0x1c0
__alloc_pages_slowpath.constprop.0+0xc9d/0xd10
__alloc_pages+0x327/0x340
__napi_alloc_skb+0x16d/0x1f0
bnxt_rx_page_skb+0x96/0x1b0 [bnxt_en]
bnxt_rx_pkt+0x201/0x15e0 [bnxt_en]
__bnxt_poll_work+0x156/0x2b0 [bnxt_en]
bnxt_poll+0xd9/0x1c0 [bnxt_en]
__napi_poll+0x2b/0x1b0
bpf_trampoline_6442524138+0x7d/0x1000
__napi_poll+0x5/0x1b0
net_rx_action+0x342/0x740
handle_softirqs+0xcf/0x2b0
irq_exit_rcu+0x6c/0x90
sysvec_apic_timer_interrupt+0x72/0x90
</IRQ>
[mfleming@cloudflare.com: update comment]
Link: https://lkml.kernel.org/r/20241015125158.3597702-1-matt@readmodwrite.com
Link: https://lkml.kernel.org/r/20241011120737.3300370-1-matt@readmodwrite.com
Link: https://lore.kernel.org/all/CAGis_TWzSu=P7QJmjD58WWiu3zjMTVKSzdOwWE8ORaGytzWJwQ@mail.gmail.com/
Fixes:
|
||
David Hildenbrand
|
7c18d48110 |
mm/pagewalk: fix usage of pmd_leaf()/pud_leaf() without present check
pmd_leaf()/pud_leaf() only implies a pmd_present()/pud_present() check on
some architectures. We really should check for
pmd_present()/pud_present() first.
This should explain the report we got on ppc64 (which has
CONFIG_PGTABLE_HAS_HUGE_LEAVES set in the config) that triggered:
VM_WARN_ON_ONCE(pmd_leaf(pmdp_get_lockless(pmdp)));
Likely we had a PMD migration entry for which pmd_leaf() did not trigger.
We raced with restoring the PMD migration entry, and suddenly saw a
pmd_leaf(). In this case, pte_offset_map_lock() saved us from more
trouble, because it rechecks the PMD value, but we would not have
processed the migration entry -- which is not too bad because the only
user of FW_MIGRATION is KSM for unsharing, and KSM only applies to small
folios.
Further, we shouldn't re-read the PMD/PUD value for our warning, the
primary purpose of the VM_WARN_ON_ONCE() is to find spurious use of
pmd_leaf()/pud_leaf() without CONFIG_PGTABLE_HAS_HUGE_LEAVES.
As a side note, we are currently not implementing FW_MIGRATION support for
PUD migration entries, which likely should exist due to hugetlb. Add a
TODO so this won't fall through the cracks if more FW_MIGRATION users get
added.
Was able to write a quick reproducer and verify that the issue no longer triggers with this fix.
https://gitlab.com/davidhildenbrand/scratchspace/-/blob/main/reproducers/move-pages-pmd-leaf.c
Without this fix after a couple of seconds in a VM with 2 NUMA nodes:
[ 54.333753] ------------[ cut here ]------------
[ 54.334901] WARNING: CPU: 20 PID: 1704 at mm/pagewalk.c:815 folio_walk_start+0x48f/0x6e0
[ 54.336455] Modules linked in: ...
[ 54.345009] CPU: 20 UID: 0 PID: 1704 Comm: move-pages-pmd- Not tainted 6.12.0-rc2+ #81
[ 54.346529] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40 04/01/2014
[ 54.348191] RIP: 0010:folio_walk_start+0x48f/0x6e0
[ 54.349134] Code: b5 ad 48 8d 35 00 00 00 00 e8 6d 59 d7 ff e8 08 74 da ff e9 9c fe ff ff 4c 8b 7c 24 08 4c 89 ff e8 26 2b be 00 e9 8a fe ff ff <0f> 0b e9 ec fe ff ff f7 c2 ff 0f 00 00 0f 85 81 fe ff ff 48 8b 02
[ 54.352660] RSP: 0018:ffffb7e4c430bc78 EFLAGS: 00010282
[ 54.353679] RAX: 80000002a3e008e7 RBX: ffff9946039aa580 RCX: ffff994380000000
[ 54.355056] RDX: ffff994606aec000 RSI: 00007f004b000000 RDI: 0000000000000000
[ 54.356440] RBP: 00007f004b000000 R08: 0000000000000591 R09: 0000000000000001
[ 54.357820] R10: 0000000000000200 R11: 0000000000000001 R12: ffffb7e4c430bd10
[ 54.359198] R13: ffff994606aec2c0 R14: 0000000000000002 R15: ffff994604a89b00
[ 54.360564] FS: 00007f004ae006c0(0000) GS:ffff9947f7400000(0000) knlGS:0000000000000000
[ 54.362111] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 54.363242] CR2: 00007f004adffe58 CR3: 0000000281e12005 CR4: 0000000000770ef0
[ 54.364615] PKRU: 55555554
[ 54.365153] Call Trace:
[ 54.365646] <TASK>
[ 54.366073] ? __warn.cold+0xb7/0x14d
[ 54.366796] ? folio_walk_start+0x48f/0x6e0
[ 54.367628] ? report_bug+0xff/0x140
[ 54.368324] ? handle_bug+0x58/0x90
[ 54.369019] ? exc_invalid_op+0x17/0x70
[ 54.369771] ? asm_exc_invalid_op+0x1a/0x20
[ 54.370606] ? folio_walk_start+0x48f/0x6e0
[ 54.371415] ? folio_walk_start+0x9e/0x6e0
[ 54.372227] do_pages_move+0x1c5/0x680
[ 54.372972] kernel_move_pages+0x1a1/0x2b0
[ 54.373804] __x64_sys_move_pages+0x25/0x30
Link: https://lkml.kernel.org/r/20241015111236.1290921-1-david@redhat.com
Fixes:
|
||
Bibo Mao
|
d2f8671045 |
LoongArch: Set initial pte entry with PAGE_GLOBAL for kernel space
There are two pages in one TLB entry on LoongArch system. For kernel space, it requires both two pte entries (buddies) with PAGE_GLOBAL bit set, otherwise HW treats it as non-global tlb, there will be potential problems if tlb entry for kernel space is not global. Such as fail to flush kernel tlb with the function local_flush_tlb_kernel_range() which supposed only flush tlb with global bit. Kernel address space areas include percpu, vmalloc, vmemmap, fixmap and kasan areas. For these areas both two consecutive page table entries should be enabled with PAGE_GLOBAL bit. So with function set_pte() and pte_clear(), pte buddy entry is checked and set besides its own pte entry. However it is not atomic operation to set both two pte entries, there is problem with test_vmalloc test case. So function kernel_pte_init() is added to init a pte table when it is created for kernel address space, and the default initial pte value is PAGE_GLOBAL rather than zero at beginning. Then only its own pte entry need update with function set_pte() and pte_clear(), nothing to do with the pte buddy entry. Signed-off-by: Bibo Mao <maobibo@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> |
||
Linus Torvalds
|
b1b4675167 |
mm: fix follow_pfnmap API lockdep assert
The lockdep asserts for the new follow_pfnmap() API "knows" that a
pfnmap always has a vma->vm_file, since that's the only way to create
such a mapping.
And that's actually true for all the normal cases. But not for the mmap
failure case, where the incomplete mapping is torn down and we have
cleared vma->vm_file because the failure occured before the file was
linked to the vma.
So this codepath does actually need to check for vm_file being NULL.
Reported-by: Jann Horn <jannh@google.com>
Fixes:
|
||
Wei Xu
|
b130ba4a62 |
mm/mglru: only clear kswapd_failures if reclaimable
lru_gen_shrink_node() unconditionally clears kswapd_failures, which can
prevent kswapd from sleeping and cause 100% kswapd cpu usage even when
kswapd repeatedly fails to make progress in reclaim.
Only clear kswap_failures in lru_gen_shrink_node() if reclaim makes some
progress, similar to shrink_node().
I happened to run into this problem in one of my tests recently. It
requires a combination of several conditions: The allocator needs to
allocate a right amount of pages such that it can wake up kswapd
without itself being OOM killed; there is no memory for kswapd to
reclaim (My test disables swap and cleans page cache first); no other
process frees enough memory at the same time.
Link: https://lkml.kernel.org/r/20241014221211.832591-1-weixugc@google.com
Fixes:
|
||
Liu Shixin
|
7528c4fb12 |
mm/swapfile: skip HugeTLB pages for unuse_vma
I got a bad pud error and lost a 1GB HugeTLB when calling swapoff. The
problem can be reproduced by the following steps:
1. Allocate an anonymous 1GB HugeTLB and some other anonymous memory.
2. Swapout the above anonymous memory.
3. run swapoff and we will get a bad pud error in kernel message:
mm/pgtable-generic.c:42: bad pud 00000000743d215d(84000001400000e7)
We can tell that pud_clear_bad is called by pud_none_or_clear_bad in
unuse_pud_range() by ftrace. And therefore the HugeTLB pages will never
be freed because we lost it from page table. We can skip HugeTLB pages
for unuse_vma to fix it.
Link: https://lkml.kernel.org/r/20241015014521.570237-1-liushixin2@huawei.com
Fixes:
|
||
Jeongjun Park
|
818f916e3a |
mm: swap: prevent possible data-race in __try_to_reclaim_swap
A report [1] was uploaded from syzbot. In the previous commit |
||
Baolin Wang
|
d60fcaf00d |
mm: khugepaged: fix the incorrect statistics when collapsing large file folios
Khugepaged already supports collapsing file large folios (including shmem mTHP) by commit |
||
David Hildenbrand
|
2b0f922323 |
mm: don't install PMD mappings when THPs are disabled by the hw/process/vma
We (or rather, readahead logic :) ) might be allocating a THP in the
pagecache and then try mapping it into a process that explicitly disabled
THP: we might end up installing PMD mappings.
This is a problem for s390x KVM, which explicitly remaps all PMD-mapped
THPs to be PTE-mapped in s390_enable_sie()->thp_split_mm(), before
starting the VM.
For example, starting a VM backed on a file system with large folios
supported makes the VM crash when the VM tries accessing such a mapping
using KVM.
Is it also a problem when the HW disabled THP using
TRANSPARENT_HUGEPAGE_UNSUPPORTED? At least on x86 this would be the case
without X86_FEATURE_PSE.
In the future, we might be able to do better on s390x and only disallow
PMD mappings -- what s390x and likely TRANSPARENT_HUGEPAGE_UNSUPPORTED
really wants. For now, fix it by essentially performing the same check as
would be done in __thp_vma_allowable_orders() or in shmem code, where this
works as expected, and disallow PMD mappings, making us fallback to PTE
mappings.
Link: https://lkml.kernel.org/r/20241011102445.934409-3-david@redhat.com
Fixes:
|
||
Kefeng Wang
|
963756aac1 |
mm: huge_memory: add vma_thp_disabled() and thp_disabled_by_hw()
Patch series "mm: don't install PMD mappings when THPs are disabled by the
hw/process/vma".
During testing, it was found that we can get PMD mappings in processes
where THP (and more precisely, PMD mappings) are supposed to be disabled.
While it works as expected for anon+shmem, the pagecache is the
problematic bit.
For s390 KVM this currently means that a VM backed by a file located on
filesystem with large folio support can crash when KVM tries accessing the
problematic page, because the readahead logic might decide to use a
PMD-sized THP and faulting it into the page tables will install a PMD
mapping, something that s390 KVM cannot tolerate.
This might also be a problem with HW that does not support PMD mappings,
but I did not try reproducing it.
Fix it by respecting the ways to disable THPs when deciding whether we can
install a PMD mapping. khugepaged should already be taking care of not
collapsing if THPs are effectively disabled for the hw/process/vma.
This patch (of 2):
Add vma_thp_disabled() and thp_disabled_by_hw() helpers to be shared by
shmem_allowable_huge_orders() and __thp_vma_allowable_orders().
[david@redhat.com: rename to vma_thp_disabled(), split out thp_disabled_by_hw() ]
Link: https://lkml.kernel.org/r/20241011102445.934409-2-david@redhat.com
Fixes:
|
||
Yang Shi
|
37f0b47c51 |
mm: khugepaged: fix the arguments order in khugepaged_collapse_file trace point
The "addr" and "is_shmem" arguments have different order in TP_PROTO and
TP_ARGS. This resulted in the incorrect trace result:
text-hugepage-644429 [276] 392092.878683: mm_khugepaged_collapse_file:
mm=0xffff20025d52c440, hpage_pfn=0x200678c00, index=512, addr=1, is_shmem=0,
filename=text-hugepage, nr=512, result=failed
The value of "addr" is wrong because it was treated as bool value, the
type of is_shmem.
Fix the order in TP_PROTO to keep "addr" is before "is_shmem" since the
original patch review suggested this order to achieve best packing.
And use "lx" for "addr" instead of "ld" in TP_printk because address is
typically shown in hex.
After the fix, the trace result looks correct:
text-hugepage-7291 [004] 128.627251: mm_khugepaged_collapse_file:
mm=0xffff0001328f9500, hpage_pfn=0x20016ea00, index=512, addr=0x400000,
is_shmem=0, filename=text-hugepage, nr=512, result=failed
Link: https://lkml.kernel.org/r/20241012011702.1084846-1-yang@os.amperecomputing.com
Fixes:
|
||
Jinjie Ruan
|
2d6a1c8356 |
mm/damon/tests/sysfs-kunit.h: fix memory leak in damon_sysfs_test_add_targets()
The sysfs_target->regions allocated in damon_sysfs_regions_alloc() is not
freed in damon_sysfs_test_add_targets(), which cause the following memory
leak, free it to fix it.
unreferenced object 0xffffff80c2a8db80 (size 96):
comm "kunit_try_catch", pid 187, jiffies 4294894363
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 0):
[<0000000001e3714d>] kmemleak_alloc+0x34/0x40
[<000000008e6835c1>] __kmalloc_cache_noprof+0x26c/0x2f4
[<000000001286d9f8>] damon_sysfs_test_add_targets+0x1cc/0x738
[<0000000032ef8f77>] kunit_try_run_case+0x13c/0x3ac
[<00000000f3edea23>] kunit_generic_run_threadfn_adapter+0x80/0xec
[<00000000adf936cf>] kthread+0x2e8/0x374
[<0000000041bb1628>] ret_from_fork+0x10/0x20
Link: https://lkml.kernel.org/r/20241010125323.3127187-1-ruanjinjie@huawei.com
Fixes:
|
||
Andy Shevchenko
|
a5e8eb2513 |
mm: remove unused stub for can_swapin_thp()
When can_swapin_thp() is unused, it prevents kernel builds with clang, `make W=1` and CONFIG_WERROR=y: mm/memory.c:4184:20: error: unused function 'can_swapin_thp' [-Werror,-Wunused-function] Fix this by removing the unused stub. See also commit |
||
Jann Horn
|
6fa1066fc5 |
mm/mremap: fix move_normal_pmd/retract_page_tables race
In mremap(), move_page_tables() looks at the type of the PMD entry and the
specified address range to figure out by which method the next chunk of
page table entries should be moved.
At that point, the mmap_lock is held in write mode, but no rmap locks are
held yet. For PMD entries that point to page tables and are fully covered
by the source address range, move_pgt_entry(NORMAL_PMD, ...) is called,
which first takes rmap locks, then does move_normal_pmd().
move_normal_pmd() takes the necessary page table locks at source and
destination, then moves an entire page table from the source to the
destination.
The problem is: The rmap locks, which protect against concurrent page
table removal by retract_page_tables() in the THP code, are only taken
after the PMD entry has been read and it has been decided how to move it.
So we can race as follows (with two processes that have mappings of the
same tmpfs file that is stored on a tmpfs mount with huge=advise); note
that process A accesses page tables through the MM while process B does it
through the file rmap:
process A process B
========= =========
mremap
mremap_to
move_vma
move_page_tables
get_old_pmd
alloc_new_pmd
*** PREEMPT ***
madvise(MADV_COLLAPSE)
do_madvise
madvise_walk_vmas
madvise_vma_behavior
madvise_collapse
hpage_collapse_scan_file
collapse_file
retract_page_tables
i_mmap_lock_read(mapping)
pmdp_collapse_flush
i_mmap_unlock_read(mapping)
move_pgt_entry(NORMAL_PMD, ...)
take_rmap_locks
move_normal_pmd
drop_rmap_locks
When this happens, move_normal_pmd() can end up creating bogus PMD entries
in the line `pmd_populate(mm, new_pmd, pmd_pgtable(pmd))`. The effect
depends on arch-specific and machine-specific details; on x86, you can end
up with physical page 0 mapped as a page table, which is likely
exploitable for user->kernel privilege escalation.
Fix the race by letting process B recheck that the PMD still points to a
page table after the rmap locks have been taken. Otherwise, we bail and
let the caller fall back to the PTE-level copying path, which will then
bail immediately at the pmd_none() check.
Bug reachability: Reaching this bug requires that you can create
shmem/file THP mappings - anonymous THP uses different code that doesn't
zap stuff under rmap locks. File THP is gated on an experimental config
flag (CONFIG_READ_ONLY_THP_FOR_FS), so on normal distro kernels you need
shmem THP to hit this bug. As far as I know, getting shmem THP normally
requires that you can mount your own tmpfs with the right mount flags,
which would require creating your own user+mount namespace; though I don't
know if some distros maybe enable shmem THP by default or something like
that.
Bug impact: This issue can likely be used for user->kernel privilege
escalation when it is reachable.
Link: https://lkml.kernel.org/r/20241007-move_normal_pmd-vs-collapse-fix-2-v1-1-5ead9631f2ea@google.com
Fixes:
|
||
Lorenzo Stoakes
|
74874c5793 |
mm/mmap: correct error handling in mmap_region()
Commit |
||
Kanchana P Sridhar
|
aa5f0fa6af |
mm: zswap: delete comments for "value" member of 'struct zswap_entry'.
Made a minor edit in the comments for 'struct zswap_entry' to delete the description of the 'value' member that was deleted in commit |
||
Patrick Roy
|
532b53cebe |
secretmem: disable memfd_secret() if arch cannot set direct map
Return -ENOSYS from memfd_secret() syscall if !can_set_direct_map(). This
is the case for example on some arm64 configurations, where marking 4k
PTEs in the direct map not present can only be done if the direct map is
set up at 4k granularity in the first place (as ARM's break-before-make
semantics do not easily allow breaking apart large/gigantic pages).
More precisely, on arm64 systems with !can_set_direct_map(),
set_direct_map_invalid_noflush() is a no-op, however it returns success
(0) instead of an error. This means that memfd_secret will seemingly
"work" (e.g. syscall succeeds, you can mmap the fd and fault in pages),
but it does not actually achieve its goal of removing its memory from the
direct map.
Note that with this patch, memfd_secret() will start erroring on systems
where can_set_direct_map() returns false (arm64 with
CONFIG_RODATA_FULL_DEFAULT_ENABLED=n, CONFIG_DEBUG_PAGEALLOC=n and
CONFIG_KFENCE=n), but that still seems better than the current silent
failure. Since CONFIG_RODATA_FULL_DEFAULT_ENABLED defaults to 'y', most
arm64 systems actually have a working memfd_secret() and aren't be
affected.
From going through the iterations of the original memfd_secret patch
series, it seems that disabling the syscall in these scenarios was the
intended behavior [1] (preferred over having
set_direct_map_invalid_noflush return an error as that would result in
SIGBUSes at page-fault time), however the check for it got dropped between
v16 [2] and v17 [3], when secretmem moved away from CMA allocations.
[1]: https://lore.kernel.org/lkml/20201124164930.GK8537@kernel.org/
[2]: https://lore.kernel.org/lkml/20210121122723.3446-11-rppt@kernel.org/#t
[3]: https://lore.kernel.org/lkml/20201125092208.12544-10-rppt@kernel.org/
Link: https://lkml.kernel.org/r/20241001080056.784735-1-roypat@amazon.co.uk
Fixes:
|
||
David Hildenbrand
|
47fa30118f |
mm/huge_memory: check pmd_special() only after pmd_present()
We should only check for pmd_special() after we made sure that we have a
present PMD. For example, if we have a migration PMD, pmd_special() might
indicate that we have a special PMD although we really don't.
This fixes confusing migration entries as PFN mappings, and not doing what
we are supposed to do in the "is_swap_pmd()" case further down in the
function -- including messing up COW, page table handling and accounting.
Link: https://lkml.kernel.org/r/20240926154234.2247217-1-david@redhat.com
Fixes:
|
||
Vlastimil Babka
|
3f1dd33f99 |
mm, slab: suppress warnings in test_leak_destroy kunit test
The test_leak_destroy kunit test intends to test the detection of stray
objects in kmem_cache_destroy(), which normally produces a warning. The
other slab kunit tests suppress the warnings in the kunit test context,
so suppress warnings and related printk output in this test as well.
Automated test running environments then don't need to learn to filter
the warnings.
Also rename the test's kmem_cache, the name was wrongly copy-pasted from
test_kfree_rcu.
Fixes:
|
||
Nilay Shroff
|
77ced98f0f |
mm, slab: fix use of SLAB_SUPPORTS_SYSFS in kmem_cache_release()
The fix implemented in commit |
||
Linus Torvalds
|
eee280841e |
19 hotfixes. 13 are cc:stable.
There's a focus on fixes for the memfd_pin_folios() work which was added into 6.11. Apart from that, the usual shower of singleton fixes. -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZvbhSAAKCRDdBJ7gKXxA jp8CAP47txk2c+tBLggog2MkQamADY5l5MT6E3fYq3ghSiKtVQEAnqX3LiQJ02tB o9LcPcVrM90QntpKrLP1CpWCVdR+zA8= =e0QC -----END PGP SIGNATURE----- Merge tag 'mm-hotfixes-stable-2024-09-27-09-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "19 hotfixes. 13 are cc:stable. There's a focus on fixes for the memfd_pin_folios() work which was added into 6.11. Apart from that, the usual shower of singleton fixes" * tag 'mm-hotfixes-stable-2024-09-27-09-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: ocfs2: fix uninit-value in ocfs2_get_block() zram: don't free statically defined names memory tiers: use default_dram_perf_ref_source in log message Revert "list: test: fix tests for list_cut_position()" kselftests: mm: fix wrong __NR_userfaultfd value compiler.h: specify correct attribute for .rodata..c_jump_table mm/damon/Kconfig: update DAMON doc URL mm: kfence: fix elapsed time for allocated/freed track ocfs2: fix deadlock in ocfs2_get_system_file_inode ocfs2: reserve space for inline xattr before attaching reflink tree mm: migrate: annotate data-race in migrate_folio_unmap() mm/hugetlb: simplify refs in memfd_alloc_folio mm/gup: fix memfd_pin_folios alloc race panic mm/gup: fix memfd_pin_folios hugetlb page allocation mm/hugetlb: fix memfd_pin_folios resv_huge_pages leak mm/hugetlb: fix memfd_pin_folios free_huge_pages leak mm/filemap: fix filemap_get_folios_contig THP panic mm: make SPLIT_PTE_PTLOCKS depend on SMP tools: fix shared radix-tree build |
||
Al Viro
|
cb787f4ac0 |
[tree-wide] finally take no_llseek out
no_llseek had been defined to NULL two years ago, in commit
|
||
Huang Ying
|
a530bbc538 |
memory tiers: use default_dram_perf_ref_source in log message
Commit |
||
Diederik de Haas
|
6901cf55de |
mm/damon/Kconfig: update DAMON doc URL
The old URL doesn't really work anymore and as the documentation has been integrated in the main kernel documentation site, change the URL to point to that. Link: https://lkml.kernel.org/r/20240924082331.11499-1-didi.debian@cknow.org Signed-off-by: Diederik de Haas <didi.debian@cknow.org> Reviewed-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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qiwu.chen
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ff7f5ad7bc |
mm: kfence: fix elapsed time for allocated/freed track
Fix elapsed time for the allocated/freed track introduced by commit |
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Jeongjun Park
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8001070cfb |
mm: migrate: annotate data-race in migrate_folio_unmap()
I found a report from syzbot [1]
This report shows that the value can be changed, but in reality, the
value of __folio_set_movable() cannot be changed because it holds the
folio refcount.
Therefore, it is appropriate to add an annotate to make KCSAN
ignore that data-race.
[1]
==================================================================
BUG: KCSAN: data-race in __filemap_remove_folio / migrate_pages_batch
write to 0xffffea0004b81dd8 of 8 bytes by task 6348 on cpu 0:
page_cache_delete mm/filemap.c:153 [inline]
__filemap_remove_folio+0x1ac/0x2c0 mm/filemap.c:233
filemap_remove_folio+0x6b/0x1f0 mm/filemap.c:265
truncate_inode_folio+0x42/0x50 mm/truncate.c:178
shmem_undo_range+0x25b/0xa70 mm/shmem.c:1028
shmem_truncate_range mm/shmem.c:1144 [inline]
shmem_evict_inode+0x14d/0x530 mm/shmem.c:1272
evict+0x2f0/0x580 fs/inode.c:731
iput_final fs/inode.c:1883 [inline]
iput+0x42a/0x5b0 fs/inode.c:1909
dentry_unlink_inode+0x24f/0x260 fs/dcache.c:412
__dentry_kill+0x18b/0x4c0 fs/dcache.c:615
dput+0x5c/0xd0 fs/dcache.c:857
__fput+0x3fb/0x6d0 fs/file_table.c:439
____fput+0x1c/0x30 fs/file_table.c:459
task_work_run+0x13a/0x1a0 kernel/task_work.c:228
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0xbe/0x130 kernel/entry/common.c:218
do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
read to 0xffffea0004b81dd8 of 8 bytes by task 6342 on cpu 1:
__folio_test_movable include/linux/page-flags.h:699 [inline]
migrate_folio_unmap mm/migrate.c:1199 [inline]
migrate_pages_batch+0x24c/0x1940 mm/migrate.c:1797
migrate_pages_sync mm/migrate.c:1963 [inline]
migrate_pages+0xff1/0x1820 mm/migrate.c:2072
do_mbind mm/mempolicy.c:1390 [inline]
kernel_mbind mm/mempolicy.c:1533 [inline]
__do_sys_mbind mm/mempolicy.c:1607 [inline]
__se_sys_mbind+0xf76/0x1160 mm/mempolicy.c:1603
__x64_sys_mbind+0x78/0x90 mm/mempolicy.c:1603
x64_sys_call+0x2b4d/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:238
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
value changed: 0xffff888127601078 -> 0x0000000000000000
Link: https://lkml.kernel.org/r/20240924130053.107490-1-aha310510@gmail.com
Fixes:
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Steve Sistare
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dc677b5f37 |
mm/hugetlb: simplify refs in memfd_alloc_folio
The folio_try_get in memfd_alloc_folio is not necessary. Delete it, and
delete the matching folio_put in memfd_pin_folios. This also avoids
leaking a ref if the memfd_alloc_folio call to hugetlb_add_to_page_cache
fails. That error path is also broken in a second way -- when its
folio_put causes the ref to become 0, it will implicitly call
free_huge_folio, but then the path *explicitly* calls free_huge_folio.
Delete the latter.
This is a continuation of the fix
"mm/hugetlb: fix memfd_pin_folios free_huge_pages leak"
[steven.sistare@oracle.com: remove explicit call to free_huge_folio(), per Matthew]
Link: https://lkml.kernel.org/r/Zti-7nPVMcGgpcbi@casper.infradead.org
Link: https://lkml.kernel.org/r/1725481920-82506-1-git-send-email-steven.sistare@oracle.com
Link: https://lkml.kernel.org/r/1725478868-61732-1-git-send-email-steven.sistare@oracle.com
Fixes:
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Steve Sistare
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ce645b9fdc |
mm/gup: fix memfd_pin_folios alloc race panic
If memfd_pin_folios tries to create a hugetlb page, but someone else
already did, then folio gets the value -EEXIST here:
folio = memfd_alloc_folio(memfd, start_idx);
if (IS_ERR(folio)) {
ret = PTR_ERR(folio);
if (ret != -EEXIST)
goto err;
then on the next trip through the "while start_idx" loop we panic here:
if (folio) {
folio_put(folio);
To fix, set the folio to NULL on error.
Link: https://lkml.kernel.org/r/1725373521-451395-6-git-send-email-steven.sistare@oracle.com
Fixes:
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Steve Sistare
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9289f020da |
mm/gup: fix memfd_pin_folios hugetlb page allocation
When memfd_pin_folios -> memfd_alloc_folio creates a hugetlb page, the
index is wrong. The subsequent call to filemap_get_folios_contig thus
cannot find it, and fails, and memfd_pin_folios loops forever. To fix,
adjust the index for the huge_page_order.
memfd_alloc_folio also forgets to unlock the folio, so the next touch of
the page calls hugetlb_fault which blocks forever trying to take the lock.
Unlock it.
Link: https://lkml.kernel.org/r/1725373521-451395-5-git-send-email-steven.sistare@oracle.com
Fixes:
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