Commits · b717d6b93b54ec2a2a7d3bb7268d3ff847cc54c5 · Kirill Smelkov / linux

30 Jul, 2022 10 commits

mm: compaction: include compound page count for scanning in pageblock isolation · b717d6b9

William Lam authored Jul 11, 2022

The number of scanned pages can be lower than the number of isolated pages
when isolating mirgratable or free pageblock. The metric is being
reported in trace event and also used in vmstat.

some example output from trace where it shows nr_taken can be greater
than nr_scanned:

Produced by kernel v5.19-rc6
kcompactd0-42 [001] ..... 1210.268022: mm_compaction_isolate_migratepages: range=(0x107ae4 ~ 0x107c00) nr_scanned=265 nr_taken=255
[...]
kcompactd0-42 [001] ..... 1210.268382: mm_compaction_isolate_freepages: range=(0x215800 ~ 0x215a00) nr_scanned=13 nr_taken=128
kcompactd0-42 [001] ..... 1210.268383: mm_compaction_isolate_freepages: range=(0x215600 ~ 0x215680) nr_scanned=1 nr_taken=128

mm_compaction_isolate_migratepages does not seem to have this
behaviour, but for the reason of consistency, nr_scanned should also be
taken care of in that side.

This behaviour is confusing since currently the count for isolated pages
takes account of compound page but not for the case of scanned pages. And
given that the number of isolated pages(nr_taken) reported in
mm_compaction_isolate_template trace event is on a single-page basis, the
ambiguity when reporting the number of scanned pages can be removed by
also including compound page count.

Link: https://lkml.kernel.org/r/20220711202806.22296-1-william.lam@bytedance.comSigned-off-by: William Lam <william.lam@bytedance.com>
Reviewed-by: Punit Agrawal <punit.agrawal@bytedance.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

b717d6b9

selftests/vm: skip 128TBswitch on unsupported arch · ac3ced5f

Adam Sindelar authored Jul 04, 2022

The test va_128TBswitch.c exercises a feature only supported on PPC and
x86_64, but it's run on other 64-bit archs as well.  Before this patch,
the test did nothing and returned 0 for KSFT_PASS.  This patch makes it
return the KSFT codes from kselftest.h, including KSFT_SKIP when
appropriate.

Verified on arm64 and x86_64.

Link: https://lkml.kernel.org/r/20220704123813.427625-1-adam@wowsignal.ioSigned-off-by: Adam Sindelar <adam@wowsignal.io>
Cc: David Vernet <void@manifault.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

ac3ced5f

selftests/vm: fix errno handling in mrelease_test · 3b8e7f5c

Adam Sindelar authored Jul 04, 2022

mrelease_test should return KSFT_SKIP when process_mrelease is not
defined, but due to a perror call consuming the errno, it returns
KSFT_FAIL.

This patch decides the exit code before calling perror.

[adam@wowsignal.io: fix remaining instances of errno mishandling]
  Link: https://lkml.kernel.org/r/20220706141602.10159-1-adam@wowsignal.io
Link: https://lkml.kernel.org/r/20220704173351.19595-1-adam@wowsignal.io
Fixes: 33776141 ("selftests: vm: add process_mrelease tests")
Signed-off-by: Adam Sindelar <adam@wowsignal.io>
Reviewed-by: David Vernet <void@manifault.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

3b8e7f5c

mm: memcontrol: do not miss MEMCG_MAX events for enforced allocations · d6e103a7

Roman Gushchin authored Jul 01, 2022

Yafang Shao reported an issue related to the accounting of bpf memory:
if a bpf map is charged indirectly for memory consumed from an
interrupt context and allocations are enforced, MEMCG_MAX events are
not raised.

It's not/less of an issue in a generic case because consequent
allocations from a process context will trigger the direct reclaim and
MEMCG_MAX events will be raised.  However a bpf map can belong to a
dying/abandoned memory cgroup, so there will be no allocations from a
process context and no MEMCG_MAX events will be triggered.

Link: https://lkml.kernel.org/r/20220702033521.64630-1-roman.gushchin@linux.devSigned-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Reported-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

d6e103a7

filemap: minor cleanup for filemap_write_and_wait_range · ccac11da

Miaohe Lin authored Jun 27, 2022

Restructure the logic in filemap_write_and_wait_range to simplify the code
and make it more consistent with file_write_and_wait_range. No functional
change intended.

Link: https://lkml.kernel.org/r/20220627132351.55680-1-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

ccac11da

mm/mmap.c: fix missing call to vm_unacct_memory in mmap_region · 7f82f922

Miaohe Lin authored Jun 18, 2022

Since the beginning, charged is set to 0 to avoid calling vm_unacct_memory
twice because vm_unacct_memory will be called by above unmap_region. But
since commit 4f74d2c8 ("vm: remove 'nr_accounted' calculations from
the unmap_vmas() interfaces"), unmap_region doesn't call vm_unacct_memory
anymore. So charged shouldn't be set to 0 now otherwise the calling to
paired vm_unacct_memory will be missed and leads to imbalanced account.

Link: https://lkml.kernel.org/r/20220618082027.43391-1-linmiaohe@huawei.com
Fixes: 4f74d2c8 ("vm: remove 'nr_accounted' calculations from the unmap_vmas() interfaces")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

7f82f922

android: binder: fix lockdep check on clearing vma · b0cab80e

Liam Howlett authored Jun 27, 2022

When munmapping a vma, the mmap_lock can be degraded to a write before
calling close() on the file handle.  The binder close() function calls
binder_alloc_set_vma() to clear the vma address, which now has a lock dep
check for writing on the mmap_lock.  Change the lockdep check to ensure
the reading lock is held while clearing and keep the write check while
writing.

Link: https://lkml.kernel.org/r/20220627151857.2316964-1-Liam.Howlett@oracle.com
Fixes: 472a68df605b ("android: binder: stop saving a pointer to the VMA")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: syzbot+da54fa8d793ca89c741f@syzkaller.appspotmail.com
Acked-by: Todd Kjos <tkjos@google.com>
Cc: "Arve Hjønnevåg" <arve@android.com>
Cc: Christian Brauner (Microsoft) <brauner@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hridya Valsaraju <hridya@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Martijn Coenen <maco@android.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

b0cab80e

android: binder: stop saving a pointer to the VMA · a43cfc87

Liam R. Howlett authored Jun 20, 2022

Do not record a pointer to a VMA outside of the mmap_lock for later use. 
This is unsafe and there are a number of failure paths *after* the
recorded VMA pointer may be freed during setup.  There is no callback to
the driver to clear the saved pointer from generic mm code.  Furthermore,
the VMA pointer may become stale if any number of VMA operations end up
freeing the VMA so saving it was fragile to being with.

Instead, change the binder_alloc struct to record the start address of the
VMA and use vma_lookup() to get the vma when needed.  Add lockdep
mmap_lock checks on updates to the vma pointer to ensure the lock is held
and depend on that lock for synchronization of readers and writers - which
was already the case anyways, so the smp_wmb()/smp_rmb() was not
necessary.

[akpm@linux-foundation.org: fix drivers/android/binder_alloc_selftest.c]
Link: https://lkml.kernel.org/r/20220621140212.vpkio64idahetbyf@revolver
Fixes: da1b9564 ("android: binder: fix the race mmap and alloc_new_buf_locked")
Reported-by: syzbot+58b51ac2b04e388ab7b0@syzkaller.appspotmail.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Christian Brauner (Microsoft) <brauner@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hridya Valsaraju <hridya@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Martijn Coenen <maco@android.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Todd Kjos <tkjos@android.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

a43cfc87

mips: rename mt_init to mips_mt_init · 15d2ce71

Liam R. Howlett authored Jul 29, 2022

Move mt_init out of the way for the maple tree.  Use mips_mt prefix to
match the rest of the functions in the file.

Link: https://lkml.kernel.org/r/20220504002554.654642-2-Liam.Howlett@oracle.comSigned-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: SeongJae Park <sj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

15d2ce71

mm: shrinkers: fix double kfree on shrinker name · 14773bfa

Tetsuo Handa authored Jul 20, 2022

syzbot is reporting double kfree() at free_prealloced_shrinker() [1], for
destroy_unused_super() calls free_prealloced_shrinker() even if
prealloc_shrinker() returned an error.  Explicitly clear shrinker name
when prealloc_shrinker() called kfree().

[roman.gushchin@linux.dev: zero shrinker->name in all cases where shrinker->name is freed]
  Link: https://lkml.kernel.org/r/YtgteTnQTgyuKUSY@castle
Link: https://syzkaller.appspot.com/bug?extid=8b481578352d4637f510 [1]
Link: https://lkml.kernel.org/r/ffa62ece-6a42-2644-16cf-0d33ef32c676@I-love.SAKURA.ne.jp
Fixes: e33c267a ("mm: shrinkers: provide shrinkers with names")
Reported-by: syzbot <syzbot+8b481578352d4637f510@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

14773bfa

26 Jul, 2022 1 commit

selftests/vm: fix va_128TBswitch.sh permissions · 187e7c41

Adam Sindelar authored Jul 08, 2022

Restore the +x bit to va_128TBswitch.sh, which got dropped from the
previous patch, somehow.

Link: https://lkml.kernel.org/r/20220708090646.34927-1-adam@wowsignal.io
Fixes: 1afd01d43efc3 ("selftests/vm: Only run 128TBswitch with 5-level paging")
Signed-off-by: Adam Sindelar <adam@wowsignal.io>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

187e7c41

18 Jul, 2022 29 commits

zram: fix unused 'zram_wb_devops' warning · 13c1c74a

Kefeng Wang authored Jun 08, 2022

drivers/block/zram/zram_drv.c:55:45: warning: 'zram_wb_devops' defined but not used [-Wunused-const-variable=]

Fix the above warning if CONFIG_ZRAM_WRITEBACK not enabled.

Link: https://lkml.kernel.org/r/20220608072534.68850-1-wangkefeng.wang@huawei.comSigned-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

13c1c74a

writeback: cleanup bdi_sched_wait() · 0d8bc0b1

Xiu Jianfeng authored Jul 13, 2022

bdi_sched_wait() is no longer used since commit 839a8e86 ("writeback:
replace custom worker pool implementation with unbound workqueue"), so
remove it.

Link: https://lkml.kernel.org/r/20220713125314.171345-1-xiujianfeng@huawei.comSigned-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

0d8bc0b1

mm/mmap: fix obsolete comment of find_extend_vma · cdb5c9e5

Miaohe Lin authored Jul 09, 2022

mmget_still_valid() has already been removed via commit 4d45e75a ("mm:
remove the now-unnecessary mmget_still_valid() hack"). Update the
corresponding comment.

Link: https://lkml.kernel.org/r/20220709092527.47778-1-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

cdb5c9e5

mm/page_vma_mapped.c: use helper function huge_pte_lock · 8f0b747d

Miaohe Lin authored Jul 09, 2022

Use helper function huge_pte_lock() to lock the huge pte to simplify the
code a bit. No functional change intended.

Link: https://lkml.kernel.org/r/20220709092440.43018-1-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

8f0b747d

mm/page_alloc: use try_cmpxchg in set_pfnblock_flags_mask · 04ec0061

Uros Bizjak authored Jul 08, 2022

Use try_cmpxchg instead of cmpxchg in set_pfnblock_flags_mask.  x86
CMPXCHG instruction returns success in ZF flag, so this change saves a
compare after cmpxchg (and related move instruction in front of cmpxchg). 
The main loop improves from:

    1c5d:	48 89 c2             	mov    %rax,%rdx
    1c60:	48 89 c1             	mov    %rax,%rcx
    1c63:	48 21 fa             	and    %rdi,%rdx
    1c66:	4c 09 c2             	or     %r8,%rdx
    1c69:	f0 48 0f b1 16       	lock cmpxchg %rdx,(%rsi)
    1c6e:	48 39 c1             	cmp    %rax,%rcx
    1c71:	75 ea                	jne    1c5d <...>

to:

    1c60:	48 89 ca             	mov    %rcx,%rdx
    1c63:	48 21 c2             	and    %rax,%rdx
    1c66:	4c 09 c2             	or     %r8,%rdx
    1c69:	f0 48 0f b1 16       	lock cmpxchg %rdx,(%rsi)
    1c6e:	75 f0                	jne    1c60 <...>

Link: https://lkml.kernel.org/r/20220708140736.8737-1-ubizjak@gmail.comSigned-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

04ec0061

mm, hugetlb: skip irrelevant nodes in show_free_areas() · dcadcf1c

Gang Li authored Jul 06, 2022

show_free_areas() allows to filter out node specific data which is
irrelevant to the allocation request.  But hugetlb_show_meminfo() still
shows hugetlb on all nodes, which is redundant and unnecessary.

Use show_mem_node_skip() to skip irrelevant nodes.  And replace
hugetlb_show_meminfo() with hugetlb_show_meminfo_node(nid).

before-and-after sample output of OOM:

before:
```
[  214.362453] Node 1 active_anon:148kB inactive_anon:4050920kB active_file:112kB inactive_file:100kB
[  214.375429] Node 1 Normal free:45100kB boost:0kB min:45576kB low:56968kB high:68360kB reserved_hig
[  214.388334] lowmem_reserve[]: 0 0 0 0 0
[  214.390251] Node 1 Normal: 423*4kB (UE) 320*8kB (UME) 187*16kB (UE) 117*32kB (UE) 57*64kB (UME) 20
[  214.397626] Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB
[  214.401518] Node 1 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB
```

after:
```
[  145.069705] Node 1 active_anon:128kB inactive_anon:4049412kB active_file:56kB inactive_file:84kB u
[  145.110319] Node 1 Normal free:45424kB boost:0kB min:45576kB low:56968kB high:68360kB reserved_hig
[  145.152315] lowmem_reserve[]: 0 0 0 0 0
[  145.155244] Node 1 Normal: 470*4kB (UME) 373*8kB (UME) 247*16kB (UME) 168*32kB (UE) 86*64kB (UME)
[  145.164119] Node 1 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB
```

Link: https://lkml.kernel.org/r/20220706034655.1834-1-ligang.bdlg@bytedance.comSigned-off-by: Gang Li <ligang.bdlg@bytedance.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

dcadcf1c

mm: percpu: use kmemleak_ignore_phys() instead of kmemleak_free() · a317ebcc

Patrick Wang authored Jul 05, 2022

Kmemleak recently added a rbtree to store the objects allocted with
physical address.  Those objects can't be freed with kmemleak_free().

According to the comments, percpu allocations are tracked by kmemleak
separately.  Kmemleak_free() was used to avoid the unnecessary
tracking.  If kmemleak_free() fails, those objects would be scanned by
kmemleak, which is unnecessary but shouldn't lead to other effects.

Use kmemleak_ignore_phys() instead of kmemleak_free() for those
objects.

Link: https://lkml.kernel.org/r/20220705113158.127600-1-patrick.wang.shcn@gmail.com
Fixes: 0c24e061 ("mm: kmemleak: add rbtree and store physical address for objects allocated with PA")
Signed-off-by: Patrick Wang <patrick.wang.shcn@gmail.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

a317ebcc

mm/mprotect: remove the redundant initialization for error · 48725bbc

Xiu Jianfeng authored Jul 04, 2022

The variable error will be assigned correctly before it is used, the
initialization is redundant, so remove it.

Link: https://lkml.kernel.org/r/20220704114112.163112-1-xiujianfeng@huawei.comSigned-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

48725bbc

mm/huge_memory: use helper macro IS_ERR_OR_NULL in split_huge_pages_pid · e75858b9