Messages in this thread | | | Date | Thu, 13 Apr 2023 17:08:08 +0800 | From | Pengfei Xu <> | Subject | Re: [Syzkaller & bisect] There is "task hung in synchronize_rcu bisect" in v6.3-rc2 kernel |
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On 2023-04-13 at 16:30:17 +0800, Hillf Danton wrote: > On Thu, 13 Apr 2023 16:03:51 +0800 Pengfei Xu <pengfei.xu@intel.com> > > > > I newly updated previous alder lake S reproduced syzkaller repro.prog and > > machineInfo0(vm info) info in log link: > > https://github.com/xupengfe/syzkaller_logs/tree/main/230315_023443_synchronize_rcu > > > > And tried debug kernel on alder lake S, there were 2 cpu in guest, and > > CPU1 reported "interrupt took 331596 ns", then kernel should not trigger > > "rcu_tasks_wait_gp" for this issue. > > [ 104.171591] memfd_create() without MFD_EXEC nor MFD_NOEXEC_SEAL, pid=334 'systemd' > > [ 126.770981] hrtimer CPU1: interrupt took 331596 ns // "rcu_tasks_wait_gp" after 15s > > [ 141.127282] rcu_tasks_wait_gp: rcu_tasks grace period number 9 (since boot) is 2571 jiffies old. > > [ 171.272100] rcu_tasks_wait_gp: rcu_tasks grace period number 9 (since boot) is 10107 jiffies old. > > [ 261.767189] rcu_tasks_wait_gp: rcu_tasks grace period number 9 (since boot) is 32731 jiffies old. > > [ 300.102911] INFO: task repro_rcu:398 blocked for more than 147 seconds. > > [ 300.103408] Not tainted 6.3.0-rc6-dbg-dirty #1 > > Similar issue, and hrtimer trace helps in both cases. I enabled "hrtimer_*" and tried again. I didn't find some clue for this issue due to lack of experience for hrtimer logs. Anyway I put the issue dmesg and hrtimer in link: https://github.com/xupengfe/syzkaller_logs/tree/main/230412_031722_synchronize_rcu/0413_debug_on_alder_lake-s
Thanks! BR.
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