qiurui
/
linux-kernelorg-stable
mirror of https://kernel.googlesource.com/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

sched_ext: Fix rq lock state in hotplug ops 

The ops.cpu_online() and ops.cpu_offline() callbacks incorrectly assume
that the rq involved in the operation is locked, which is not the case
during hotplug, triggering the following warning:

  WARNING: CPU: 1 PID: 20 at kernel/sched/sched.h:1504 handle_hotplug+0x280/0x340

Fix by not tracking the target rq as locked in the context of
ops.cpu_online() and ops.cpu_offline().

Fixes: 18853ba782 ("sched_ext: Track currently locked rq")
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Tested-by: Changwoo Min <changwoo@igalia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Andrea Righi 2025-04-28 23:43:20 +02:00 committed by Tejun Heo
parent e7dcd1304b
commit e38be1c764
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
kernel/sched/ext.c
View File

@ -3477,9 +3477,9 @@ static void handle_hotplug(struct rq *rq, bool online)
scx_idle_update_selcpu_topology(&scx_ops);
if (online && SCX_HAS_OP(cpu_online))
SCX_CALL_OP(SCX_KF_UNLOCKED, cpu_online, rq, cpu);
SCX_CALL_OP(SCX_KF_UNLOCKED, cpu_online, NULL, cpu);
else if (!online && SCX_HAS_OP(cpu_offline))
SCX_CALL_OP(SCX_KF_UNLOCKED, cpu_offline, rq, cpu);
SCX_CALL_OP(SCX_KF_UNLOCKED, cpu_offline, NULL, cpu);
else
scx_ops_exit(SCX_ECODE_ACT_RESTART | SCX_ECODE_RSN_HOTPLUG,
"cpu %d going %s, exiting scheduler", cpu,