From: Preeti U Murthy Date: Wed, 2 Jul 2014 03:49:35 +0000 (+0530) Subject: powerpc/powernv: Check for IRQHAPPENED before sleeping X-Git-Tag: firefly_0821_release~176^2~3545^2~13 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=c733cf83bbd2b0978456822cdac8c726085dcc14;p=firefly-linux-kernel-4.4.55.git powerpc/powernv: Check for IRQHAPPENED before sleeping Commit 8d6f7c5a: "powerpc/powernv: Make it possible to skip the IRQHAPPENED check in power7_nap()" added code that prevents cpus from checking for pending interrupts just before entering sleep state, which is wrong. These interrupts are delivered during the soft irq disabled state of the cpu. A cpu cannot enter any idle state with pending interrupts because they will never be serviced until the next time the cpu is woken up by some other interrupt. Its only then that the pending interrupts are replayed. This can result in device timeouts or warnings about this cpu being stuck. This patch fixes ths issue by ensuring that cpus check for pending interrupts just before entering any idle state as long as they are not in the path of split core operations. Signed-off-by: Preeti U Murthy Acked-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt --- diff --git a/arch/powerpc/kernel/idle_power7.S b/arch/powerpc/kernel/idle_power7.S index 2480256272d4..5cf3d367190d 100644 --- a/arch/powerpc/kernel/idle_power7.S +++ b/arch/powerpc/kernel/idle_power7.S @@ -131,7 +131,7 @@ _GLOBAL(power7_nap) _GLOBAL(power7_sleep) li r3,1 - li r4,0 + li r4,1 b power7_powersave_common /* No return */