On Mon, Feb 27, 2023 at 11:16:26AM -0500, Steven Rostedt wrote: > On Tue, 28 Feb 2023 00:11:51 +0800 > Zhouyi Zhou <zhouzhouyi@xxxxxxxxx> wrote: > > > > Yes certainly, the rcu_head is allocated on the caller side so it > > > could have been trampled while the callback was still in flight. > > Thank you all for your guidance, I learned a lot during this process > > > > > > > OR it could be a bug with RCU if the synchronize_rcu() ended before the > > > > grace periods have finished. > > Thanks again. > > > > By the way, the syzkaller on my local machine has been running for 8 > > hours, only three bugs reported[1][2][3], but they don't seem to be > > related to Sanan's original report. > > Maybe there are some configuration mismatches between us.The test > > continues, I will report to you once I have any new discovery. > > Note, the above races (either bug, the one that tramples on something in > RCU flight, or a synchronize_sched() returning early) may be extremely hard > to hit. It could have been the planets were lined up just right to hit the > bug, and won't happen for another 27,000 years. Which turns into once per week or two across a million-system fleet. ;-) Not that I know of any fleets running syzkaller... Thanx, Paul
