Annotate flexible array members of 'struct ocfs2_local_alloc' and 'struct
ocfs2_inline_data' with '__counted_by_le()' attribute to improve array
bounds checking when CONFIG_UBSAN_BOUNDS is enabled, and prefer the
convenient 'memset()' over an explicit loop to simplify
'ocfs2_clear_local_alloc()'.
Link: https://lkml.kernel.org/r/20251021105518.119953-1-dmantipov@yandex.ru
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
syzbot constructed a corrupted image, which resulted in el->l_count from
the b-tree extent block being 0. Since the length of the l_recs array
depends on l_count, reading its member e_blkno triggered the out-of-bounds
access reported by syzbot in [1].
The loop terminates when l_count is 0, similar to when next_free is 0.
[1]
UBSAN: array-index-out-of-bounds in fs/ocfs2/alloc.c:1838:11
index 0 is out of range for type 'struct ocfs2_extent_rec[] __counted_by(l_count)' (aka 'struct ocfs2_extent_rec[]')
Call Trace:
__ocfs2_find_path+0x606/0xa40 fs/ocfs2/alloc.c:1838
ocfs2_find_leaf+0xab/0x1c0 fs/ocfs2/alloc.c:1946
ocfs2_get_clusters_nocache+0x172/0xc60 fs/ocfs2/extent_map.c:418
ocfs2_get_clusters+0x505/0xa70 fs/ocfs2/extent_map.c:631
ocfs2_extent_map_get_blocks+0x202/0x6a0 fs/ocfs2/extent_map.c:678
ocfs2_read_virt_blocks+0x286/0x930 fs/ocfs2/extent_map.c:1001
ocfs2_read_dir_block fs/ocfs2/dir.c:521 [inline]
ocfs2_find_entry_el fs/ocfs2/dir.c:728 [inline]
ocfs2_find_entry+0x3e4/0x2090 fs/ocfs2/dir.c:1120
ocfs2_find_files_on_disk+0xdf/0x310 fs/ocfs2/dir.c:2023
ocfs2_lookup_ino_from_name+0x52/0x100 fs/ocfs2/dir.c:2045
_ocfs2_get_system_file_inode fs/ocfs2/sysfile.c:136 [inline]
ocfs2_get_system_file_inode+0x326/0x770 fs/ocfs2/sysfile.c:112
ocfs2_init_global_system_inodes+0x319/0x660 fs/ocfs2/super.c:461
ocfs2_initialize_super fs/ocfs2/super.c:2196 [inline]
ocfs2_fill_super+0x4432/0x65b0 fs/ocfs2/super.c:993
get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691
vfs_get_tree+0x92/0x2a0 fs/super.c:1751
fc_mount fs/namespace.c:1199 [inline]
Link: https://lkml.kernel.org/r/tencent_4D99464FA28D9225BE0DBA923F5DF6DD8C07@qq.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Reported-by: syzbot+151afab124dfbc5f15e6@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=151afab124dfbc5f15e6
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When the filesystem is being mounted, the kernel panics while the data
regarding slot map allocation to the local node, is being written to the
disk. This occurs because the value of slot map buffer head block number,
which should have been greater than or equal to `OCFS2_SUPER_BLOCK_BLKNO`
(evaluating to 2) is less than it, indicative of disk metadata corruption.
This triggers BUG_ON(bh->b_blocknr < OCFS2_SUPER_BLOCK_BLKNO) in
ocfs2_write_block(), causing the kernel to panic.
This is fixed by introducing function ocfs2_validate_slot_map_block() to
validate slot map blocks. It first checks if the buffer head passed to it
is up to date and valid, else it panics the kernel at that point itself.
Further, it contains an if condition block, which checks if
`bh->b_blocknr` is lesser than `OCFS2_SUPER_BLOCK_BLKNO`; if yes, then
ocfs2_error is called, which prints the error log, for debugging purposes,
and the return value of ocfs2_error() is returned. If the if condition is
false, value 0 is returned by ocfs2_validate_slot_map_block().
This function is used as validate function in calls to ocfs2_read_blocks()
in ocfs2_refresh_slot_info() and ocfs2_map_slot_buffers().
Link: https://lkml.kernel.org/r/20251215184600.13147-1-activprithvi@gmail.com
Signed-off-by: Prithvi Tambewagh <activprithvi@gmail.com>
Reported-by: syzbot+c818e5c4559444f88aa0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c818e5c4559444f88aa0
Tested-by: <syzbot+c818e5c4559444f88aa0@syzkaller.appspotmail.com>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
After introducing 2f26f58df0 ("ocfs2: annotate flexible array members
with __counted_by_le()"), syzbot has reported the following issue:
UBSAN: array-index-out-of-bounds in fs/ocfs2/xattr.c:1955:3
index 2 is out of range for type 'struct ocfs2_xattr_entry[]
__counted_by(xh_count)' (aka 'struct ocfs2_xattr_entry[]')
...
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
ubsan_epilogue+0xa/0x40 lib/ubsan.c:233
__ubsan_handle_out_of_bounds+0xe9/0xf0 lib/ubsan.c:455
ocfs2_xa_remove_entry+0x36d/0x3e0 fs/ocfs2/xattr.c:1955
...
To address this issue, 'xh_entries[]' member removal should be performed
before actually changing 'xh_count', thus making sure that all array
accesses matches the boundary checks performed by UBSAN.
Link: https://lkml.kernel.org/r/20251211155949.774485-1-dmantipov@yandex.ru
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Reported-by: syzbot+cf96bc82a588a27346a8@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=cf96bc82a588a27346a8
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Deepanshu Kartikey <kartikey406@gmail.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When reading an inode from disk, ocfs2_validate_inode_block() performs
various sanity checks but does not validate the size of inline data. If
the filesystem is corrupted, an inode's i_size can exceed the actual
inline data capacity (id_count).
This causes ocfs2_dir_foreach_blk_id() to iterate beyond the inline data
buffer, triggering a use-after-free when accessing directory entries from
freed memory.
In the syzbot report:
- i_size was 1099511627576 bytes (~1TB)
- Actual inline data capacity (id_count) is typically <256 bytes
- A garbage rec_len (54648) caused ctx->pos to jump out of bounds
- This triggered a UAF in ocfs2_check_dir_entry()
Fix by adding a validation check in ocfs2_validate_inode_block() to ensure
inodes with inline data have i_size <= id_count. This catches the
corruption early during inode read and prevents all downstream code from
operating on invalid data.
Link: https://lkml.kernel.org/r/20251212052132.16750-1-kartikey406@gmail.com
Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com>
Reported-by: syzbot+c897823f699449cc3eb4@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c897823f699449cc3eb4
Tested-by: syzbot+c897823f699449cc3eb4@syzkaller.appspotmail.com
Link: https://lore.kernel.org/all/20251211115231.3560028-1-kartikey406@gmail.com/T/ [v1]
Link: https://lore.kernel.org/all/20251212040400.6377-1-kartikey406@gmail.com/T/ [v2]
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
'struct configfs_item_operations' and 'configfs_group_operations' are not
modified in this driver.
Constifying these structures moves some data to a read-only section, so
increases overall security, especially when the structure holds some
function pointers.
On a x86_64, with allmodconfig, as an example:
Before:
======
text data bss dec hex filename
74011 19312 5280 98603 1812b fs/ocfs2/cluster/heartbeat.o
After:
=====
text data bss dec hex filename
74171 19152 5280 98603 1812b fs/ocfs2/cluster/heartbeat.o
Link: https://lkml.kernel.org/r/7c7c00ba328e5e514d8debee698154039e9640dd.1765708880.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
After ocfs2 gained the ability to reclaim suballocator free block group
(BGs), a suballocator block group may be released. This change causes the
xfstest case generic/426 to fail.
generic/426 expects return value -ENOENT or -ESTALE, but the current code
triggers -EROFS.
Call stack before ocfs2 gained the ability to reclaim bg:
ocfs2_fh_to_dentry //or ocfs2_fh_to_parent
ocfs2_get_dentry
+ ocfs2_test_inode_bit
| ocfs2_test_suballoc_bit
| + ocfs2_read_group_descriptor //Since ocfs2 never releases the bg,
| | //the bg block was always found.
| + *res = ocfs2_test_bit //unlink was called, and the bit is zero
|
+ if (!set) //because the above *res is 0
status = -ESTALE //the generic/426 expected return value
Current call stack that triggers -EROFS:
ocfs2_get_dentry
ocfs2_test_inode_bit
ocfs2_test_suballoc_bit
ocfs2_read_group_descriptor
+ if reading a released bg, validation fails and triggers -EROFS
How to fix:
Since the read BG is already released, we must avoid triggering -EROFS.
With this commit, we use ocfs2_read_hint_group_descriptor() to detect the
released BG block. This approach quietly handles this type of error and
returns -EINVAL, which triggers the caller's existing conversion path to
-ESTALE.
[dan.carpenter@linaro.org: fix uninitialized variable]
Link: https://lkml.kernel.org/r/dc37519fd2470909f8c65e26c5131b8b6dde2a5c.1766043917.git.dan.carpenter@linaro.org
Link: https://lkml.kernel.org/r/20251212074505.25962-3-heming.zhao@suse.com
Signed-off-by: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Su Yue <glass.su@suse.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "ocfs2: give ocfs2 the ability to reclaim suballocator free
bg", v6.
This patch (of 2):
The current ocfs2 code can't reclaim suballocator block group space. In
some cases, this causes ocfs2 to hold onto a lot of space. For example,
when creating lots of small files, the space is held/managed by the
'//inode_alloc'. After the user deletes all the small files, the space
never returns to the '//global_bitmap'. This issue prevents ocfs2 from
providing the needed space even when there is enough free space in a small
ocfs2 volume.
This patch gives ocfs2 the ability to reclaim suballocator free space when
the block group is freed. For performance reasons, this patch keeps the
first suballocator block group active.
Link: https://lkml.kernel.org/r/20251212074505.25962-2-heming.zhao@suse.com
Signed-off-by: Heming Zhao <heming.zhao@suse.com>
Reviewed-by: Su Yue <glass.su@suse.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
'struct configfs_item_operations' and 'configfs_group_operations' are not
modified in this driver.
Constifying these structures moves some data to a read-only section, so
increases overall security, especially when the structure holds some
function pointers.
On a x86_64, with allmodconfig, as an example:
Before:
======
text data bss dec hex filename
16339 11001 384 27724 6c4c kernel/crash_dump_dm_crypt.o
After:
=====
text data bss dec hex filename
16499 10841 384 27724 6c4c kernel/crash_dump_dm_crypt.o
Link: https://lkml.kernel.org/r/d046ee5666d2f6b1a48ca1a222dfbd2f7c44462f.1765735035.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Coiby Xu <coxu@redhat.com>
Tested-by: Coiby Xu <coxu@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The current OID registry parser uses 64 bit arithmetic which limits us to
supporting 64 bit or smaller OIDs. This isn't usually a problem except
that it prevents us from representing the 2.25. prefix OIDs which are the
OID representation of UUIDs and have a 128 bit number following the
prefix. Rather than import not often used perl arithmetic modules,
replace the current perl 64 bit arithmetic with a callout to bc, which is
arbitrary precision, for decimal to base 2 conversion, then do pure string
operations on the base 2 number.
[James.Bottomley@HansenPartnership.com: tidy up perl with better my placement also set bc to arbitrary size]
Link: https://lkml.kernel.org/r/dbc90c344c691ed988640a28367ff895b5ef2604.camel@HansenPartnership.com
Link: https://lkml.kernel.org/r/833c858cd74533203b43180208734b84f1137af0.camel@HansenPartnership.com
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Blaise Boscaccy <bboscaccy@linux.microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
__tlb_remove_page_size() is only used in tlb_remove_page_size() with
@delay_remap set to false and it is passed directly to
__tlb_remove_folio_pages_size().
Remove @delay_remap of __tlb_remove_page_size() and call
__tlb_remove_folio_pages_size() with false @delay_remap.
Link: https://lkml.kernel.org/r/20251231030026.15938-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: SeongJae Park <sj@kernel.org>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The 'h' length modifier in '%hd' is unnecessary as short integers are
promoted to int in variadic functions. Use '%d' instead.
Checkpatch flags the 'h' modifier as unnecessary for this reason, and
many other subsystems have moved to using %d for promoted types.
Hence, I think this patch aligns with kernel coding practices.
Link: https://lkml.kernel.org/r/20251228154456.2386-1-kdipendra88@gmail.com
Signed-off-by: Dipendra Khadka <kdipendra88@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove a redundant test case from damos_test_commit_quota_goal() as it is
already covered. Instead, add a new test for DAMOS_QUOTA_SOME_MEM_PSI_US,
which was previously not tested.
Link: https://lkml.kernel.org/r/20251224042200.2061847-6-shu17az@gmail.com
Signed-off-by: Shu Anzai <shu17az@gmail.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add a test case in damon_test_merge_regions_of() to verify that two
adjacent regions are not merged if the resulting region would exceed the
specified size limit.
Link: https://lkml.kernel.org/r/20251224042200.2061847-4-shu17az@gmail.com
Signed-off-by: Shu Anzai <shu17az@gmail.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Extend damon_test_merge_two() to verify the 'age' and 'nr_accesses_bp'
fields.
Link: https://lkml.kernel.org/r/20251224042200.2061847-3-shu17az@gmail.com
Signed-off-by: Shu Anzai <shu17az@gmail.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm/damon/tests/core-kunit: extend existing test scenarios",
v2.
Improve the KUnit test coverage for DAMON.
The five patches in this series respectively extend damon_test_split_at(),
damon_test_merge_two(), damon_test_merge_regions_of(),
damon_test_split_regions_of(), and damos_test_commit_quota_goal().
This patch (of 5):
Extend damon_test_split_at() to verify the 'age' field.
Link: https://lkml.kernel.org/r/20251224042200.2061847-1-shu17az@gmail.com
Link: https://lkml.kernel.org/r/20251224042200.2061847-2-shu17az@gmail.com
Signed-off-by: Shu Anzai <shu17az@gmail.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Several helper functions for managing node and zone states have become
obsolete and no longer have any callers within the kernel.
inc_node_state()
inc_zone_state()
dec_zone_state()
This commit removes the dead code.
Link: https://lkml.kernel.org/r/20251225210213.2553-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Joshua Hahn <joshua.hahnjy@gmail.com>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The test supports arm64 as well so the comment is incorrect. And there's
a check for arm64 in va_high_addr_switch.c.
Link: https://lkml.kernel.org/r/20251221040025.3159990-5-chuhu@redhat.com
Fixes: 983e760bcd ("selftest/mm: va_high_addr_switch: add ppc64 support check")
Fixes: f556acc2fa ("selftests/mm: skip test for non-LPA2 and non-LVA systems")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Reviewed-by: Luiz Capitulino <luizcap@redhat.com>
Cc: "David Hildenbrand (Red Hat)" <david@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: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When the first test failed, and the hugetlb test passed, the result would
be pass, but we expect a fail. Fix this issue by returning fail if either
is not KSFT_PASS.
Link: https://lkml.kernel.org/r/20251221040025.3159990-4-chuhu@redhat.com
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Reviewed-by: Luiz Capitulino <luizcap@redhat.com>
Cc: "David Hildenbrand (Red Hat)" <david@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: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
arm64 and x86_64 has the same nr_hugepages requriement for running the
va_high_addr_switch test. Since commit d9d957bd7b ("selftests/mm: alloc
hugepages in va_high_addr_switch test"), the setup can be done in
va_high_addr_switch.sh. So remove the duplicated setup.
Link: https://lkml.kernel.org/r/20251221040025.3159990-3-chuhu@redhat.com
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Reviewed-by: Luiz Capitulino <luizcap@redhat.com>
Cc: Luiz Capitulino <luizcap@redhat.com>
Cc: "David Hildenbrand (Red Hat)" <david@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: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The va_high_addr_switch test requires 6 hugepages, not 5. If running the
test directly by: ./va_high_addr_switch.sh, the test will hit a mmap 'FAIL'
caused by not enough hugepages:
mmap(addr_switch_hint - hugepagesize, 2*hugepagesize, MAP_HUGETLB): 0x7f330f800000 - OK
mmap(addr_switch_hint , 2*hugepagesize, MAP_FIXED | MAP_HUGETLB): 0xffffffffffffffff - FAILED
The failure can't be hit if run the tests by running 'run_vmtests.sh -t
hugevm' because the nr_hugepages is set to 128 at the beginning of
run_vmtests.sh and va_high_addr_switch.sh skip the setup of nr_hugepages
because already enough.
Link: https://lkml.kernel.org/r/20251221040025.3159990-2-chuhu@redhat.com
Fixes: d9d957bd7b ("selftests/mm: alloc hugepages in va_high_addr_switch test")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Reviewed-by: Luiz Capitulino <luizcap@redhat.com>
Cc: "David Hildenbrand (Red Hat)" <david@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: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Fix va_high_addr_switch.sh test failure - again", v2.
The series address several issues exist for the va_high_addr_switch test:
1) the test return value is ignored in va_high_addr_switch.sh.
2) the va_high_addr_switch test requires 6 hugepages not 5.
3) the reurn value of the first test in va_high_addr_switch.c can be
overridden by the second test.
4) the nr_hugepages setup in run_vmtests.sh for arm64 can be done in
va_high_addr_switch.sh too.
5) update a comment for check_test_requirements.
This patch: (of 5)
The return value should be return value of va_high_addr_switch, otherwise
a test failure would be silently ignored.
Link: https://lkml.kernel.org/r/20251221040025.3159990-1-chuhu@redhat.com
Fixes: d9d957bd7b ("selftests/mm: alloc hugepages in va_high_addr_switch test")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Reviewed-by: Luiz Capitulino <luizcap@redhat.com>
Cc: Luiz Capitulino <luizcap@redhat.com>
Cc: "David Hildenbrand (Red Hat)" <david@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: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The hugetlb cgroup usage wait loops in charge_reserved_hugetlb.sh were
unbounded and could hang forever if the expected cgroup file value never
appears (e.g. due to write_to_hugetlbfs in Error mapping).
=== Error log ===
# uname -r
6.12.0-xxx.el10.aarch64+64k
# ls /sys/kernel/mm/hugepages/hugepages-*
hugepages-16777216kB/ hugepages-2048kB/ hugepages-524288kB/
#./charge_reserved_hugetlb.sh -cgroup-v2
# -----------------------------------------
...
# nr hugepages = 10
# writing cgroup limit: 5368709120
# writing reseravation limit: 5368709120
...
# write_to_hugetlbfs: Error mapping the file: Cannot allocate memory
# Waiting for hugetlb memory reservation to reach size 2684354560.
# 0
# Waiting for hugetlb memory reservation to reach size 2684354560.
# 0
# Waiting for hugetlb memory reservation to reach size 2684354560.
# 0
# Waiting for hugetlb memory reservation to reach size 2684354560.
# 0
# Waiting for hugetlb memory reservation to reach size 2684354560.
# 0
# Waiting for hugetlb memory reservation to reach size 2684354560.
# 0
...
Introduce a small helper, wait_for_file_value(), and use it for:
- waiting for reservation usage to drop to 0,
- waiting for reservation usage to reach a given size,
- waiting for fault usage to reach a given size.
This makes the waits consistent and adds a hard timeout (60 tries with 1s
sleep) so the test fails instead of stalling indefinitely.
Link: https://lkml.kernel.org/r/20251221122639.3168038-4-liwang@redhat.com
Signed-off-by: Li Wang <liwang@redhat.com>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
charge_reserved_hugetlb.sh mounts a hugetlbfs instance at /mnt/huge with a
fixed size of 256M. On systems with large base hugepages (e.g. 512MB),
this is smaller than a single hugepage, so the hugetlbfs mount ends up
with zero capacity (often visible as size=0 in mount output).
As a result, write_to_hugetlbfs fails with ENOMEM and the test can hang
waiting for progress.
=== Error log ===
# uname -r
6.12.0-xxx.el10.aarch64+64k
#./charge_reserved_hugetlb.sh -cgroup-v2
# -----------------------------------------
...
# nr hugepages = 10
# writing cgroup limit: 5368709120
# writing reseravation limit: 5368709120
...
# write_to_hugetlbfs: Error mapping the file: Cannot allocate memory
# Waiting for hugetlb memory reservation to reach size 2684354560.
# 0
# Waiting for hugetlb memory reservation to reach size 2684354560.
# 0
...
# mount |grep /mnt/huge
none on /mnt/huge type hugetlbfs (rw,relatime,seclabel,pagesize=512M,size=0)
# grep -i huge /proc/meminfo
...
HugePages_Total: 10
HugePages_Free: 10
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 524288 kB
Hugetlb: 5242880 kB
Drop the mount args with 'size=256M', so the filesystem capacity is sufficient
regardless of HugeTLB page size.
Link: https://lkml.kernel.org/r/20251221122639.3168038-3-liwang@redhat.com
Fixes: 29750f71a9 ("hugetlb_cgroup: add hugetlb_cgroup reservation tests")
Signed-off-by: Li Wang <liwang@redhat.com>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "selftests/mm: hugetlb cgroup charging: robustness fixes", v3.
This series fixes a few issues in the hugetlb cgroup charging selftests
(write_to_hugetlbfs.c + charge_reserved_hugetlb.sh) that show up on
systems with large hugepages (e.g. 512MB) and when failures cause the
test to wait indefinitely.
On an aarch64 64k page kernel with 512MB hugepages, the test consistently
fails in write_to_hugetlbfs with ENOMEM and then hangs waiting for the
expected usage values. The root cause is that charge_reserved_hugetlb.sh
mounts hugetlbfs with a fixed size=256M, which is smaller than a single
hugepage, resulting in a mount with size=0 capacity.
In addition, write_to_hugetlbfs previously parsed -s via atoi() into an
int, which can overflow and print negative sizes.
Reproducer / environment:
- Kernel: 6.12.0-xxx.el10.aarch64+64k
- Hugepagesize: 524288 kB (512MB)
- ./charge_reserved_hugetlb.sh -cgroup-v2
- Observed mount: pagesize=512M,size=0 before this series
After applying the series, the test completes successfully on the above
setup.
This patch (of 3):
write_to_hugetlbfs currently parses the -s size argument with atoi() into
an int. This silently accepts malformed input, cannot report overflow,
and can truncate large sizes.
=== Error log ===
# uname -r
6.12.0-xxx.el10.aarch64+64k
# ls /sys/kernel/mm/hugepages/hugepages-*
hugepages-16777216kB/ hugepages-2048kB/ hugepages-524288kB/
#./charge_reserved_hugetlb.sh -cgroup-v2
# -----------------------------------------
...
# nr hugepages = 10
# writing cgroup limit: 5368709120
# writing reseravation limit: 5368709120
...
# Writing to this path: /mnt/huge/test
# Writing this size: -1610612736 <--------
Switch the size variable to size_t and parse -s with sscanf("%zu", ...).
Also print the size using %zu.
This avoids incorrect behavior with large -s values and makes the utility
more robust.
Link: https://lkml.kernel.org/r/20251221122639.3168038-1-liwang@redhat.com
Link: https://lkml.kernel.org/r/20251221122639.3168038-2-liwang@redhat.com
Signed-off-by: Li Wang <liwang@redhat.com>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We presently skip regions with hugepages entirely when trying to do
contiguous page allocation. This will cause otherwise-movable 2MB HugeTLB
pages to be considered unmovable, and makes 1GB gigantic page allocation
less reliable on systems utilizing both.
Commit 4d73ba5fa7 ("mm: page_alloc: skip regions with hugetlbfs pages
when allocating 1G pages") skipped all HugePage containing regions because
it can cause significant delays in 1G allocation (as HugeTLB migrations
may fail for a number of reasons).
Instead, if hugepage migration is enabled, consider regions with hugepages
smaller than the target contiguous allocation request as valid targets for
allocation.
We optimize for the existing behavior by searching for non-hugetlb regions
in a first pass, then retrying the search to include hugetlb only on
failure. This allows the existing fast-path to remain the default case
with a slow-path fallback to increase reliability.
We only fallback to the slow path if a hugetlb region was detected, and we
do a full re-scan because the zones/blocks may have changed during the
first pass (and it's not worth further complexity).
isolate_migrate_pages_block() has similar hugetlb filter logic, and the
hugetlb code does a migratable check in folio_isolate_hugetlb() during
isolation. The code servicing the allocation and migration already
supports this exact use case.
To test, allocate a bunch of 2MB HugeTLB pages (in this case 48GB) and
then attempt to allocate some 1G HugeTLB pages (in this case 4GB) (Scale
to your machine's memory capacity).
echo 24576 > .../hugepages-2048kB/nr_hugepages
echo 4 > .../hugepages-1048576kB/nr_hugepages
Prior to this patch, the 1GB page reservation can fail if no contiguous
1GB pages remain. After this patch, the kernel will try to move 2MB pages
and successfully allocate the 1GB pages (assuming overall sufficient
memory is available). Also tested this while a program had the 2MB
reservations mapped, and the 1GB reservation still succeeds.
folio_alloc_gigantic() is the primary user of alloc_contig_pages(),
other users are debug or init-time allocations and largely unaffected.
- ppc/memtrace is a debugfs interface
- x86/tdx memory allocation occurs once on module-init
- kfence/core happens once on module (late) init
- THP uses it in debug_vm_pgtable_alloc_huge_page at __init time
Link: https://lkml.kernel.org/r/20251221124656.2362540-1-gourry@gourry.net
Signed-off-by: Gregory Price <gourry@gourry.net>
Suggested-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/linux-mm/6fe3562d-49b2-4975-aa86-e139c535ad00@redhat.com/
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This reintroduces a concept removed by: commit d6cb41cc44 ("mm, hugetlb:
remove hugepages_treat_as_movable sysctl")
This sysctl provides flexibility between ZONE_MOVABLE use cases:
1) onlining memory in ZONE_MOVABLE to maintain hotplug compatibility
2) onlining memory in ZONE_MOVABLE to make hugepage allocate reliable
When ZONE_MOVABLE is used to make huge page allocation more reliable,
disallowing gigantic pages memory in this region is pointless. If hotplug
is not a requirement, we can loosen the restrictions to allow 1GB gigantic
pages in ZONE_MOVABLE.
Since 1GB can be difficult to migrate / has impacts on compaction /
defragmentation, we don't enable this by default. Notably, 1GB pages can
only be migrated if another 1GB page is available - so hot-unplug will
fail if such a page cannot be found.
However, since there are scenarios where gigantic pages are migratable, we
should allow use of these on movable regions.
When not valid 1GB is available for migration, hot-unplug will retry
indefinitely (or until interrupted). For example:
echo 0 > node0/hugepages/..-1GB/nr_hugepages # clear node0 1GB pages
echo 1 > node1/hugepages/..-1GB/nr_hugepages # reserve node1 1GB page
./alloc_huge_node1 & # Allocate a 1GB page on node1
./node1_offline & # attempt to offline all node1 memory
echo 1 > node0/hugepages/..-1GB/nr_hugepages # reserve node0 1GB page
In this example, node1_offline will block indefinitely until the final
step, when a node0 1GB page is made available.
Note: Boot-time CMA is not possible for driver-managed hotplug memory, as
CMA requires the memory to be registered as SystemRAM at boot time.
Additionally, 1GB huge pages are not supported by THP.
Link: https://lkml.kernel.org/r/20251221125603.2364174-1-gourry@gourry.net
Signed-off-by: Gregory Price <gourry@gourry.net>
Suggested-by: David Rientjes <rientjes@google.com>
Link: https://lore.kernel.org/all/20180201193132.Hk7vI_xaU%25akpm@linux-foundation.org/
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "David Hildenbrand (Red Hat)" <david@kernel.org>
Cc: Gregory Price <gourry@gourry.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
commit d240629148 ("fork: use __mt_dup() to duplicate maple tree in
dup_mmap()"), removed the only user and mas_expected_entries has been
removed, since commit e3852a1213 ("maple_tree: Drop bulk insert
support"). Also cleanup the mas_expected_entries in maple_tree.h.
No functional change.
Link: https://lkml.kernel.org/r/20251106110929.3522073-1-guanwentao@uniontech.com
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Cheng Nie <niecheng1@uniontech.com>
Cc: Guan Wentao <guanwentao@uniontech.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Jann Horn <jannh@google.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The current description of contexts where it's invalid to make GFP_ATOMIC
and GFP_NOWAIT calls is rather vague.
Replace this with a direct description of the actual contexts of concern
and refer to the RT docs where this is explained more discursively.
While rejigging this prose, also move the documentation of GFP_NOWAIT to
the GFP_NOWAIT section.
Link: https://lore.kernel.org/all/d912480a-5229-4efe-9336-b31acded30f5@suse.cz/
Link: https://lkml.kernel.org/r/20251219-b4-gfp_atomic-comment-v2-1-4c4ce274c2b6@google.com
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Hildenbrand (Red Hat) <david@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: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This helper is no longer used after commit fd2825b076 ("mm/gup: remove
pXX_devmap usage from get_user_pages()").
Link: https://lkml.kernel.org/r/20251219-gup-cleanup-v1-1-348a70d9eecb@tencent.com
Signed-off-by: Kairui Song <kasong@tencent.com>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since commit cc638f329e ("mm, thp: tweak reclaim/compaction effort of
local-only and all-node allocations"), THP page fault allocations have
settled on the following scheme (from the commit log):
1. local node only THP allocation with no reclaim, just compaction.
2. for madvised VMA's or when synchronous compaction is enabled always - THP
allocation from any node with effort determined by global defrag setting
and VMA madvise
3. fallback to base pages on any node
Recent customer reports however revealed we have a gap in step 1 above.
What we have seen is excessive reclaim due to THP page faults on a NUMA
node that's close to its high watermark, while other nodes have plenty of
free memory.
The problem with step 1 is that it promises no reclaim after the
compaction attempt, however reclaim is only avoided for certain compaction
outcomes (deferred, or skipped due to insufficient free base pages), and
not e.g. when compaction is actually performed but fails (we did see
compact_fail vmstat counter increasing).
THP page faults can therefore exhibit a zone_reclaim_mode-like behavior,
which is not the intention.
Thus add a check for __GFP_THISNODE that corresponds to this exact
situation and prevents continuing with reclaim/compaction once the initial
compaction attempt isn't successful in allocating the page.
Note that commit cc638f329e has not introduced this over-reclaim
possibility; it appears to exist in some form since commit 2f0799a0ff
("mm, thp: restore node-local hugepage allocations"). Followup commits
b39d0ee263 ("mm, page_alloc: avoid expensive reclaim when compaction may
not succeed") and cc638f329e have moved in the right direction, but left
the abovementioned gap.
Link: https://lkml.kernel.org/r/20251219-costly-noretry-thisnode-fix-v1-1-e1085a4a0c34@suse.cz
Fixes: 2f0799a0ff ("mm, thp: restore node-local hugepage allocations")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Pedro Falcato <pfalcato@suse.de>
Acked-by: Zi Yan <ziy@nvidia.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: "David Hildenbrand (Red Hat)" <david@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
A false-positive compile warnings with -Wformat-trucation was introduced
by commit 47179fe035 ("mm/hugetlb_cgroup: prepare cftypes based on
template") on arch s390. Suppress it by replacing snprintf() with
scnprintf().
mm/hugetlb_cgroup.c: In function 'hugetlb_cgroup_file_init':
mm/hugetlb_cgroup.c:829:44: warning: '%s' directive output may be truncated writing up to 1623 bytes into a region of size between 32 and 63 [-Wformat-truncation=]
829 | snprintf(cft->name, MAX_CFTYPE_NAME, "%s.%s", buf, tmpl->name);
| ^~
Link: https://lkml.kernel.org/r/20251222072359.3626182-1-xiujianfeng@huaweicloud.com
Fixes: 47179fe035 ("mm/hugetlb_cgroup: prepare cftypes based on template")
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202512212332.9lFRbgdS-lkp@intel.com/
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: "David Hildenbrand (Red Hat)" <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>
Correct several typos in comments across files in mm/
[akpm@linux-foundation.org: also fix comment grammar, per SeongJae]
Link: https://lkml.kernel.org/r/20251218150906.25042-1-klourencodev@gmail.com
Signed-off-by: Kevin Lourenco <klourencodev@gmail.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Correct minor spelling mistakes in several files under mm/damon. No
functional changes.
Link: https://lkml.kernel.org/r/20251217181216.47576-1-klourencodev@gmail.com
Signed-off-by: Kevin Lourenco <klourencodev@gmail.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The KMSG_COMPONENT macro is a leftover of the s390 specific "kernel
message catalog" from 2008 [1] which never made it upstream.
The macro was added to s390 code to allow for an out-of-tree patch which
used this to generate unique message ids. Also this out-of-tree doesn't
exist anymore.
The pattern of how the KMSG_COMPONENT is used was partially also used for
non s390 specific code, for whatever reasons.
Remove the macro in order to get rid of a pointless indirection.
Link: https://lkml.kernel.org/r/20251126143602.2207435-1-hca@linux.ibm.com
Link: https://lwn.net/Articles/292650/ [1]
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use bool for 'hashdist' and replace simple_strtoul() with kstrtobool() for
parsing the 'hashdist=' boot parameter. Unlike simple_strtoul(), which
returns an unsigned long, kstrtobool() converts the string directly to
bool and avoids implicit casting.
Check the return value of kstrtobool() and reject invalid values. This
adds error handling while preserving behavior for existing values, and
removes use of the deprecated simple_strtoul() helper. The current code
silently sets 'hashdist = 0' if parsing fails, instead of leaving the
default value (HASHDIST_DEFAULT) unchanged.
Additionally, kstrtobool() accepts common boolean strings such as "on" and
"off".
Link: https://lkml.kernel.org/r/20251217110214.50807-1-thorsten.blum@linux.dev
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If PAGE_SIZE is larger than 4k and if you have a system with a large
number of CPUs, this test can require a very large amount of memory
leading to oom-killer firing. Given the type of allocation, the kernel
won't have anything to kill, causing the system to stall.
Add a parameter to the test_vmalloc driver to represent the number of
times a percpu object will be allocated. Calculate this in
test_vmalloc.sh to be 90% of available memory or the current default of
35000, whichever is smaller.
Link: https://lkml.kernel.org/r/20251201181848.1216197-1-audra@redhat.com
Signed-off-by: Audra Mitchell <audra@redhat.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.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: Rafael Aquini <raquini@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
struct maple_alloc is deprecated after the maple tree conversion to
sheaves, remove the references from the header file.
Link: https://lkml.kernel.org/r/20251203224511.469978-1-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Laptop mode was introduced to save battery, by delaying and consolidating
writes and thereby maximize the time rotating hard drives wouldn't have to
spin.
Luckily, rotating hard drives, with their high spin-up times and power
draw, are a thing of the past for battery-powered devices. Reclaim has
also since changed to not write single filesystem pages anymore, and
regular filesystem writeback is lumpy by design.
The juice doesn't appear worth the squeeze anymore. The footprint of the
feature is small, but nevertheless it's a complicating factor in mm,
block, filesystems. Developers don't think about it, and it likely hasn't
been tested with new reclaim and writeback changes in years.
Let's sunset it. Keep the sysctl with a deprecation warning around for a
few more cycles, but remove all functionality behind it.
[akpm@linux-foundation.org: fix Documentation/admin-guide/laptops/index.rst]
Link: https://lkml.kernel.org/r/20251216185201.GH905277@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Deepanshu Kartikey <kartikey406@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
pp_in_progress makes sure that only one post-processing (writeback or
recomrpession) is active at any given time. Functionality wise it,
basically, shadows zram init_lock, when init_lock is acquired in writer
mode.
Switch recompress_store() and writeback_store() to take zram init_lock in
writer mode, like all store() sysfs handlers should do, so that we can
drop pp_in_progress. Recompression and writeback can be somewhat slow, so
holding init_lock in writer mode can block zram attrs reads, but in
reality the only zram attrs reads that take place are mm_stat reads, and
usually it's the same process that reads mm_stat and does recompression or
writeback.
Link: https://lkml.kernel.org/r/20251216071342.687993-1-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The damon_stat_build_ctx() function sets the values of intervals_goal
structure members. These values are applied to damon_ctx in
damon_set_attrs(). However, It is resetting the values that were already
applied previously to the same values. I suggest removing this code as it
constitutes duplicate execution.
Link: https://patch.msgid.link/20251206011716.7185-1-rgbi3307@gmail.com
Link: https://lkml.kernel.org/r/20251216073440.40891-1-sj@kernel.org
Signed-off-by: JaeJoon Jung <rgbi3307@gmail.com>
Reviewed-by: Enze Li <lienze@kylinos.cn>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
DAMON users can read DAMOS stats via DAMON sysfs interface. It enables
efficient, simple and flexible usages of the stats. Especially for
systems not having advanced tools like perf or bpftrace, that can be
useful. But if the advanced tools are available, exposing the stats via
tracepoint can reduce unnecessary reimplementation of the wheels. Add a
new tracepoint for DAMOS stats, namely damos_stat_after_apply_interval.
The tracepoint is triggered for each scheme's apply interval and exposes
the whole stat values. If the user needs sub-apply interval information
for any chance, damos_before_apply tracepoint could be used.
Link: https://lkml.kernel.org/r/20251216080128.42991-13-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add a new DAMON sysfs file for setting and getting the newly introduced
per-DAMON-snapshot level DAMOS deactivation control parameter,
max_nr_snapshots. The file has a name same to the parameter and placed
under the damos stat directory.
Link: https://lkml.kernel.org/r/20251216080128.42991-9-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There are DAMOS use cases that require user-space centric control of its
activation and deactivation. Having the control plane on the user-space,
or using DAMOS as a way for monitoring results collection are such
examples.
DAMON parameters online commit, DAMOS quotas and watermarks can be useful
for this purpose. However, those features work only at the
sub-DAMON-snapshot level. In some use cases, the DAMON-snapshot level
control is required. For example, in DAMOS-based monitoring results
collection use case, the user online-installs a DAMOS scheme with
DAMOS_STAT action, wait it be applied to whole regions of a single
DAMON-snapshot, retrieves the stats and tried regions information, and
online-uninstall the scheme. It is efficient to ensure the lifetime of
the scheme as no more no less one snapshot consumption.
To support such use cases, introduce a new DAMOS core API per-scheme
parameter, namely max_nr_snapshots. As the name implies, it is the upper
limit of nr_snapshots, which is a DAMOS stat that represents the number of
DAMON-snapshots that the scheme has fully applied. If the limit is set
with a non-zero value and nr_snapshots reaches or exceeds the limit, the
scheme is deactivated.
Link: https://lkml.kernel.org/r/20251216080128.42991-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Commit 0e92c2ee9f ("mm/damon/schemes: account scheme actions that
successfully applied") has replaced ->stat_count and ->stat_sz of 'struct
damos' with ->stat. The commit mistakenly did not update the related
kernel doc comment, though. Update the comment.
Link: https://lkml.kernel.org/r/20251216080128.42991-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
