Commit-ID: 74eed0163d0def3fce27228d9ccf3d36e207b286 Gitweb: http://git.kernel.org/tip/74eed0163d0def3fce27228d9ccf3d36e207b286 Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx> AuthorDate: Wed, 20 Feb 2013 22:00:48 +0100 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitDate: Thu, 21 Feb 2013 20:52:24 +0100 irq: Ensure irq_exit() code runs with interrupts disabled We had already a few problems with code called from irq_exit() when interrupted from a nesting interrupt. This can happen on architectures which do not define __ARCH_IRQ_EXIT_IRQS_DISABLED. __ARCH_IRQ_EXIT_IRQS_DISABLED should go away and we want to make it mandatory to call irq_exit() with interrupts disabled. As a temporary protection disable interrupts for those architectures which do not define __ARCH_IRQ_EXIT_IRQS_DISABLED and add a WARN_ONCE when an architecture which defines __ARCH_IRQ_EXIT_IRQS_DISABLED calls irq_exit() with interrupts enabled. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1302202155320.22263@ionos --- kernel/softirq.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/kernel/softirq.c b/kernel/softirq.c index f5cc25f..f2a9346 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -341,6 +341,14 @@ static inline void invoke_softirq(void) */ void irq_exit(void) { +#ifndef __ARCH_IRQ_EXIT_IRQS_DISABLED + unsigned long flags; + + local_irq_save(flags); +#else + WARN_ON_ONCE(!irqs_disabled()); +#endif + account_irq_exit_time(current); trace_hardirq_exit(); sub_preempt_count(IRQ_EXIT_OFFSET); @@ -354,6 +362,9 @@ void irq_exit(void) #endif rcu_irq_exit(); sched_preempt_enable_no_resched(); +#ifndef __ARCH_IRQ_EXIT_IRQS_DISABLED + local_irq_restore(flags); +#endif } /* -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html