From: Vladimir Oltean <olte...@gmail.com> Date: Sun, 29 Sep 2019 01:07:45 +0300
> Currently this stack trace can be seen with CONFIG_DEBUG_ATOMIC_SLEEP=y: ... > Enabling RX timestamping will logically disturb the fastpath (processing > of meta frames). Replace bool hwts_rx_en with a bit that is checked > atomically from the fastpath and temporarily unset from the sleepable > context during a change of the RX timestamping process (a destructive > operation anyways, requires switch reset). > If found unset, the fastpath will just drop any received meta frame and > not take the meta_lock at all. > > Fixes: a602afd200f5 ("net: dsa: sja1105: Expose PTP timestamping ioctls to > userspace") > Signed-off-by: Vladimir Oltean <olte...@gmail.com> Well, two things: 1) Even assuming #2 wasn't true, you're adding the missing initialization of meta_lock and that would need to be mentioned in the commit message. 2) After these changes meta_lock is no longer used so it should be removed.