2.6.31-stable review patch. If anyone has any objections, please let us know. ------------------ From: Kevin Hilman commit 246eb7f0ed1a8aeddec5313137767658f378949b upstream. In the case where cpuidle_idle_call() returns before changing state due to a need_resched(), it was returning with IRQs disabled. The idle path assumes that the platform specific idle code returns with interrupts enabled (although this too is undocumented AFAICT) and on ARM we have a WARN_ON(!(irqs_disabled()) when returning from the idle loop, so the user-visible effects were only a warning since interrupts were eventually re-enabled later. On x86, this same problem exists, but there is no WARN_ON() to detect it. As on ARM, the interrupts are eventually re-enabled, so I'm not sure of any actual bugs triggered by this. It's primarily a correctness/consistency fix. This patch ensures IRQs are (re)enabled before returning. Reported-by: Hemanth V Signed-off-by: Kevin Hilman Cc: Arjan van de Ven Cc: Len Brown Cc: Venkatesh Pallipadi Cc: Ingo Molnar Cc: "Rafael J. Wysocki" Tested-by: Martin Michlmayr Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- drivers/cpuidle/cpuidle.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -75,8 +75,11 @@ static void cpuidle_idle_call(void) #endif /* ask the governor for the next state */ next_state = cpuidle_curr_governor->select(dev); - if (need_resched()) + if (need_resched()) { + local_irq_enable(); return; + } + target_state = &dev->states[next_state]; /* enter the state and update stats */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/