A single bugfix for RCU to prevent taking a lock in NMI context.

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Merge tag 'core-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RCU fix from Thomas Gleixner:
 "A single bugfix for RCU to prevent taking a lock in NMI context"

* tag 'core-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rcu: Don't acquire lock in NMI handler in rcu_nmi_enter_common()
This commit is contained in:
Linus Torvalds 2020-04-19 11:16:00 -07:00
commit 5e7de58127

View File

@ -825,7 +825,7 @@ static __always_inline void rcu_nmi_enter_common(bool irq)
rcu_cleanup_after_idle();
incby = 1;
} else if (tick_nohz_full_cpu(rdp->cpu) &&
} else if (irq && tick_nohz_full_cpu(rdp->cpu) &&
rdp->dynticks_nmi_nesting == DYNTICK_IRQ_NONIDLE &&
READ_ONCE(rdp->rcu_urgent_qs) &&
!READ_ONCE(rdp->rcu_forced_tick)) {