Re: [GIT PULL rcu/urgent] Don't acquire lock in NMI handler (v5.7)

From: Ingo Molnar
Date: Tue Apr 14 2020 - 02:37:46 EST


* Paul E. McKenney <paulmck@xxxxxxxxxx> wrote:

> Hello!
>
> This pull request contains a single commit that avoid acquiring
> a lock when rcu_nmi_enter_common() is invoked from an NMI handler.
> This issue can of course result in self-deadlock, and the fix is quite
> straightforward. I am therefore putting it forward for the current
> release (v5.7) instead of following my normal process, which would
> delay it until v5.8.
>
> This fix has been subjected to rcutorture, kbuild test robot, and -next
> testing and is available at:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git urgent-for-mingo
>
> for you to fetch changes up to bf37da98c51825c90432d340e135cced37a7460d:
>
> rcu: Don't acquire lock in NMI handler in rcu_nmi_enter_common() (2020-04-05 14:22:15 -0700)
>
> ----------------------------------------------------------------
> Paul E. McKenney (1):
> rcu: Don't acquire lock in NMI handler in rcu_nmi_enter_common()
>
> kernel/rcu/tree.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

Pulled into tip:core/urgent, thanks Paul!

Ingo