Stefan Metzmacher <metze@xxxxxxxxx> writes: > Am 25.03.21 um 12:24 schrieb Sasha Levin: >> From: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> >> >> [ Upstream commit 4db4b1a0d1779dc159f7b87feb97030ec0b12597 ] >> >> Just like we don't allow normal signals to IO threads, don't deliver a >> STOP to a task that has PF_IO_WORKER set. The IO threads don't take >> signals in general, and have no means of flushing out a stop either. >> >> Longer term, we may want to look into allowing stop of these threads, >> as it relates to eg process freezing. For now, this prevents a spin >> issue if a SIGSTOP is delivered to the parent task. >> >> Reported-by: Stefan Metzmacher <metze@xxxxxxxxx> >> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> >> Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> >> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> >> --- >> kernel/signal.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/kernel/signal.c b/kernel/signal.c >> index 55526b941011..00a3840f6037 100644 >> --- a/kernel/signal.c >> +++ b/kernel/signal.c >> @@ -288,7 +288,8 @@ bool task_set_jobctl_pending(struct task_struct *task, unsigned long mask) >> JOBCTL_STOP_SIGMASK | JOBCTL_TRAPPING)); >> BUG_ON((mask & JOBCTL_TRAPPING) && !(mask & JOBCTL_PENDING_MASK)); >> >> - if (unlikely(fatal_signal_pending(task) || (task->flags & PF_EXITING))) >> + if (unlikely(fatal_signal_pending(task) || >> + (task->flags & (PF_EXITING | PF_IO_WORKER)))) >> return false; >> >> if (mask & JOBCTL_STOP_SIGMASK) >> > > Again, why is this proposed for 5.11 and 5.10 already? Has the bit about the io worker kthreads been backported? If so this isn't horrible. If not this is nonsense. Eric
