Messages in this thread | | | Date | Tue, 10 Sep 2019 15:32:42 +0100 | From | Greg KH <> | Subject | Re: [BACKPORT 4.14.y v2 2/6] locking/lockdep: Add debug_locks check in __lock_downgrade() |
| |
On Thu, Sep 05, 2019 at 11:07:14AM +0800, Baolin Wang wrote: > From: Waiman Long <longman@redhat.com> > > [Upstream commit 513e1073d52e55b8024b4f238a48de7587c64ccf] > > Tetsuo Handa had reported he saw an incorrect "downgrading a read lock" > warning right after a previous lockdep warning. It is likely that the > previous warning turned off lock debugging causing the lockdep to have > inconsistency states leading to the lock downgrade warning. > > Fix that by add a check for debug_locks at the beginning of > __lock_downgrade(). > > Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> > Reported-by: syzbot+53383ae265fb161ef488@syzkaller.appspotmail.com > Signed-off-by: Waiman Long <longman@redhat.com> > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Linus Torvalds <torvalds@linux-foundation.org> > Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> > Cc: Peter Zijlstra <peterz@infradead.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Will Deacon <will.deacon@arm.com> > Link: https://lkml.kernel.org/r/1547093005-26085-1-git-send-email-longman@redhat.com > Signed-off-by: Ingo Molnar <mingo@kernel.org> > Signed-off-by: Baolin Wang <baolin.wang@linaro.org> > --- > kernel/locking/lockdep.c | 3 +++ > 1 file changed, 3 insertions(+)
Why isn't this relevant for 4.19.y? I can't add a patch to 4.14.y and then have someone upgrade to 4.19.y and not have the same fix in there, that would be a regression.
So can you redo this series also with a 4.19.y set at the same so we don't get out of sync? I've queued up your first patch already as that was in 4.19.y (and also needed in 4.9.y).
thanks,
greg k-h
| |