leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

cgroup: freezer: call cgroup_enter_frozen() with preemption disabled in ptrace_stop()

Browse Source 
ptrace_stop() does preempt_enable_no_resched() to avoid the preemption,
but after that cgroup_enter_frozen() does spin_lock/unlock and this adds
another preemption point.

Reported-and-tested-by: Bruce Ashfield <bruce.ashfield@gmail.com>
Fixes: 76f969e894 ("cgroup: cgroup v2 freezer")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Oleg Nesterov 2019-10-09 17:02:30 +02:00 committed by Tejun Heo
parent 9e208aa06c
commit 937c6b27c7
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
kernel/signal.c
View File

@ -2205,8 +2205,8 @@ static void ptrace_stop(int exit_code, int why, int clear_code, kernel_siginfo_t
*/
preempt_disable();
read_unlock(&tasklist_lock);
preempt_enable_no_resched();
cgroup_enter_frozen();
preempt_enable_no_resched();
freezable_schedule();
cgroup_leave_frozen(true);
} else {