Re: [PATCH] sched/core: fix illegal RCU from offline CPUs

From: Qian Cai
Date: Mon Jan 13 2020 - 08:43:00 EST




> On Jan 13, 2020, at 3:22 AM, Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> wrote:
>
> Is commit 7283094ec3db318e ("kernel, oom: fix potential pgd_lock deadlock from
> __mmdrop") about only softirq? Is it guaranteed that smp_call_function_single()
> does not hit such race? Then just my overcareful...

That commit looks like a different issue. We are not call mmdrop() from softirq here.