| Message ID | 20200326181602.7yLEsvDFG%akpm@linux-foundation.org |
|---|---|
| State | New |
| Headers | show |
| Series | [merged] mm-memcg-fix-corruption-on-64-bit-divisor-in-memoryhigh-throttling.patch removed from -mm tree | expand |
--- a/mm/memcontrol.c~mm-memcg-fix-corruption-on-64-bit-divisor-in-memoryhigh-throttling +++ a/mm/memcontrol.c @@ -2339,7 +2339,7 @@ void mem_cgroup_handle_over_high(void) */ clamped_high = max(high, 1UL); - overage = div_u64((u64)(usage - high) << MEMCG_DELAY_PRECISION_SHIFT, + overage = div64_u64((u64)(usage - high) << MEMCG_DELAY_PRECISION_SHIFT, clamped_high); penalty_jiffies = ((u64)overage * overage * HZ)
The patch titled Subject: mm, memcg: fix corruption on 64-bit divisor in memory.high throttling has been removed from the -mm tree. Its filename was mm-memcg-fix-corruption-on-64-bit-divisor-in-memoryhigh-throttling.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Chris Down <chris@chrisdown.name> Subject: mm, memcg: fix corruption on 64-bit divisor in memory.high throttling 0e4b01df8659 had a bunch of fixups to use the right division method. However, it seems that after all that it still wasn't right -- div_u64 takes a 32-bit divisor. The headroom is still large (2^32 pages), so on mundane systems you won't hit this, but this should definitely be fixed. Link: http://lkml.kernel.org/r/80780887060514967d414b3cd91f9a316a16ab98.1584036142.git.chris@chrisdown.name Fixes: 0e4b01df8659 ("mm, memcg: throttle allocators when failing reclaim over memory.high") Signed-off-by: Chris Down <chris@chrisdown.name> Reported-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <guro@fb.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Nathan Chancellor <natechancellor@gmail.com> Cc: <stable@vger.kernel.org> [5.4.x+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> --- mm/memcontrol.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)