Commit 174aefd8 authored by Odin Ugedal's avatar Odin Ugedal Committed by Zheng Zengkai
Browse files

sched/fair: Fix CFS bandwidth hrtimer expiry type

stable inclusion
from stable-5.10.53
commit 892387e7619ecb339dd43c4ab916256d6c4c0001
bugzilla: 175574 https://gitee.com/openeuler/kernel/issues/I4DTUX

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=892387e7619ecb339dd43c4ab916256d6c4c0001



--------------------------------

[ Upstream commit 72d0ad7c ]

The time remaining until expiry of the refresh_timer can be negative.
Casting the type to an unsigned 64-bit value will cause integer
underflow, making the runtime_refresh_within return false instead of
true. These situations are rare, but they do happen.

This does not cause user-facing issues or errors; other than
possibly unthrottling cfs_rq's using runtime from the previous period(s),
making the CFS bandwidth enforcement less strict in those (special)
situations.

Signed-off-by: default avatarOdin Ugedal <odin@uged.al>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarBen Segall <bsegall@google.com>
Link: https://lore.kernel.org/r/20210629121452.18429-1-odin@uged.al


Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarChen Jun <chenjun102@huawei.com>
Acked-by: default avatarWeilong Chen <chenweilong@huawei.com>
Signed-off-by: default avatarChen Jun <chenjun102@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent 7863bba5
Loading
Loading
Loading
Loading
0% Loading or .
You are about to add 0 people to the discussion. Proceed with caution.
Please to comment