Peter, will this fix be sent to linux.git shortly? syzbot is generating many corrupted reports due to this race.
On 2019/01/14 22:36, Peter Zijlstra wrote: > On Thu, Jan 10, 2019 at 11:21:13AM +0100, Dmitry Vyukov wrote: >> On Thu, Jan 10, 2019 at 5:04 AM Waiman Long <[email protected]> wrote: >>> >>> 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(). >>> >>> Signed-off-by: Waiman Long <[email protected]> >>> Reported-by: Tetsuo Handa <[email protected]> >> >> Please also add: >> >> Reported-by: [email protected] >> >> for tracking purposes. But Tetsuo deserves lots of credit for debugging it. > > I made that: > > Reported-by: Tetsuo Handa <[email protected]> > Debugged-by: Tetsuo Handa <[email protected]> > Reported-by: [email protected]

