Re: [cgroup] 3c87862ca1: WARNING:at_kernel/softirq.c:#__local_bh_enable_ip

[Tadeusz Struk]

On 6/9/22 01:56, kernel test robot wrote:
> Greeting,
>
> FYI, we noticed the following commit (built with gcc-11):
>
> commit: 3c87862ca13147416d900cf82ca56bb2f23910bf ("[PATCH v2] cgroup: serialize css kill and release paths")
> url:https://github.com/intel-lab-lkp/linux/commits/Tadeusz-Struk/cgroup-serialize-css-kill-and-release-paths/20220606-014132
> base:https://git.kernel.org/cgit/linux/kernel/git/tj/cgroup.git  for-next
> patch link:https://lore.kernel.org/netdev/20220603181321.443716-1-tadeusz.struk@xxxxxxxxxx
>
> in testcase: boot
>
> on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G
>
> caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):
>
>
>
> If you fix the issue, kindly add following tag
> Reported-by: kernel test robot<oliver.sang@xxxxxxxxx>
>
>
> [ 55.821003][ C1] WARNING: CPU: 1 PID: 1 at kernel/softirq.c:363 __local_bh_enable_ip (kernel/softirq.c:363)

Looks like that will need to be spin_lock_irq(&css->lock) instead of spin_lock_bh(&css->lock)
I can respin the patch, but I would like to request some feedback on it first.

Tejun, Michal
Are you interested in fixing this at syzbot issue all? Do you have any more feedback on this?

--
Thanks,
Tadeusz