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| author | Thomas Gleixner <tglx@linutronix.de> | 2013-02-20 22:00:48 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2013-02-21 20:52:24 +0100 |
| commit | 74eed0163d0def3fce27228d9ccf3d36e207b286 (patch) | |
| tree | 28aa386f02468504846ebec731e9ba432e4a4010 /kernel/softirq.c | |
| parent | e5ab012c3271990e8457055c25cafddc1ae8aa6b (diff) | |
| download | lwn-74eed0163d0def3fce27228d9ccf3d36e207b286.tar.gz lwn-74eed0163d0def3fce27228d9ccf3d36e207b286.zip | |
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@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1302202155320.22263@ionos
Diffstat (limited to 'kernel/softirq.c')
| -rw-r--r-- | kernel/softirq.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/kernel/softirq.c b/kernel/softirq.c index f5cc25f147a6..f2a934673008 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 } /* |