On Mon, Apr 26, 2021 at 08:16:34PM +0200, Thomas Gleixner wrote: > On Mon, Apr 26 2021 at 11:42, Andrew Halaney wrote: > > On Tue, Apr 06, 2021 at 05:19:52PM -0500, Andrew Halaney wrote: > >> There's no chance of sleeping here, the reader is giving up the > >> lock and possibly waking up the writer who is waiting on it. > >> > >> Reported-by: Chunyu Hu <chuhu@xxxxxxxxxx> > >> Signed-off-by: Andrew Halaney <ahalaney@xxxxxxxxxx> > >> --- > >> Hello, > >> > >> I ran into a warning caused by this, and I think the warning is > >> incorrect. Please let me know if I'm wrong! > >> I'm working off of linux-5.12.y-rt, but this applies cleanly to older > >> stable branches as well. > >> > >> Thanks, > >> Andrew > >> > >> kernel/locking/rwsem-rt.c | 1 - > >> 1 file changed, 1 deletion(-) > >> > >> diff --git a/kernel/locking/rwsem-rt.c b/kernel/locking/rwsem-rt.c > >> index 274172d5bb3a..b61edc4dcb73 100644 > >> --- a/kernel/locking/rwsem-rt.c > >> +++ b/kernel/locking/rwsem-rt.c > >> @@ -198,7 +198,6 @@ void __up_read(struct rw_semaphore *sem) > >> if (!atomic_dec_and_test(&sem->readers)) > >> return; > >> > >> - might_sleep(); > >> raw_spin_lock_irq(&m->wait_lock); > >> /* > >> * Wake the writer, i.e. the rtmutex owner. It might release the > >> -- > >> 2.30.2 > > > > Just a gentle follow up, any feedback? > > Looks correct. Will go into the next rt-release. > > Thanks, > > tglx > Hi Thomas, I see a new release (v5.13-rt1) was created, and with it rwsem was overhauled entirely making this patch pointless for linux-rt-devel. That being said, it's a little unclear to me how RT only patches make their way to the maintained branches over in linux-stable-rt. I think it should be applied to: v4.9-rt v4.14-rt v4.19-rt v5.4-rt v5.10-rt to remove the incorrect warning, unless those branches plan to backport the latest RT patchset with the new rwsem implementation. Is there a proper way for me signal that? Thanks, Andrew
