On Thu 28-05-20 23:10:20, Feng Tang wrote:
[...]
> If it's true, then there could be 2 solutions, one is to
> skip the WARN_ONCE as it has no practical value, as the real
> check is the following code, the other is to rectify the
> percpu counter when the policy is changing to OVERCOMMIT_NEVER.
I would simply drop the WARN_ONCE. Looking at the history this has been
added by 82f71ae4a2b8 ("mm: catch memory commitment underflow") to have
a safety check for issues which have been fixed. There doesn't seem to
be any bug reports mentioning this splat since then so it is likely just
spending cycles for a hot path (yes many people run with DEBUG_VM)
without a strong reason.
--
Michal Hocko
SUSE Labs
