The patch titled Subject: mm: restore node stat checking in /proc/sys/vm/stat_refresh has been added to the -mm tree. Its filename is mm-restore-node-stat-checking-in-proc-sys-vm-stat_refresh.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-restore-node-stat-checking-in-proc-sys-vm-stat_refresh.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-restore-node-stat-checking-in-proc-sys-vm-stat_refresh.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Hugh Dickins <hughd@xxxxxxxxxx> Subject: mm: restore node stat checking in /proc/sys/vm/stat_refresh v4.7 52b6f46bc163 ("mm: /proc/sys/vm/stat_refresh to force vmstat update") introduced vmstat_refresh(), with its vmstat underflow checking; then v4.8 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@xxxxxx> 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@xxxxxxxxxx> Cc: Roman Gushchin <guro@xxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vmstat.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/mm/vmstat.c~mm-restore-node-stat-checking-in-proc-sys-vm-stat_refresh +++ a/mm/vmstat.c @@ -1875,6 +1875,14 @@ int vmstat_refresh(struct ctl_table *tab } } #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) _ Patches currently in -mm which might be from hughd@xxxxxxxxxx are mm-restore-node-stat-checking-in-proc-sys-vm-stat_refresh.patch mm-no-more-einval-from-proc-sys-vm-stat_refresh.patch mm-proc-sys-vm-stat_refresh-skip-checking-known-negative-stats.patch mm-proc-sys-vm-stat_refresh-stop-checking-monotonic-numa-stats.patch