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author | Hugh Dickins <hughd@google.com> | 2021-05-05 03:37:51 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-05-05 20:27:25 +0200 |
commit | 76d8cc3c8f45cc597726616f11db4180f7e21ce0 (patch) | |
tree | 9e19cf3c53360f70c0e26f0439e3eb30d485b2ac /mm | |
parent | mm/ksm: remove unused parameter from remove_trailing_rmap_items() (diff) | |
download | linux-76d8cc3c8f45cc597726616f11db4180f7e21ce0.tar.xz linux-76d8cc3c8f45cc597726616f11db4180f7e21ce0.zip |
mm: restore node stat checking in /proc/sys/vm/stat_refresh
In v4.7 commit 52b6f46bc163 ("mm: /proc/sys/vm/stat_refresh to force
vmstat update") introduced vmstat_refresh(), with its vmstat underflow
checking; then in v4.8 commit 75ef71840539 ("mm, vmstat: add
infrastructure for per-node vmstats") split NR_VM_NODE_STAT_ITEMS out of
NR_VM_ZONE_STAT_ITEMS without updating vmstat_refresh(): so it has been
missing out much of the vmstat underflow checking ever since.
Reinstate it.
Thanks to Roman Gushchin <guro@fb.com> for tangentially pointing this out.
Link: https://lkml.kernel.org/r/alpine.LSU.2.11.2102251502240.13363@eggly.anvils
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/vmstat.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/mm/vmstat.c b/mm/vmstat.c index 49a8456ec079..14d0ba4fd46b 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1875,6 +1875,14 @@ int vmstat_refresh(struct ctl_table *table, int write, } } #endif + for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { + val = atomic_long_read(&vm_node_stat[i]); + if (val < 0) { + pr_warn("%s: %s %ld\n", + __func__, node_stat_name(i), val); + err = -EINVAL; + } + } if (err) return err; if (write) |