[PATCH] 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 even cores which enter sleep
on idle, from checking for pending interrupts. Fix this.

Signed-off-by: Preeti U Murthy <redacted>
---

 arch/powerpc/kernel/idle_power7.S |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/idle_power7.S b/arch/powerpc/kernel/idle_power7.S
index 2480256..5cf3d36 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 */
 

On Mon, 2014-06-30 at 11:54 +0530, Preeti U Murthy wrote:

Commit 8d6f7c5a: "powerpc/powernv: Make it possible to skip the IRQHAPPEN=

ED

check in power7_nap()" added code that prevents even cores which enter sl=

eep

on idle, from checking for pending interrupts. Fix this.
=20
Signed-off-by: Preeti U Murthy <redacted>

Acked-by: Michael Neuling <redacted>

_power7.S

On Mon, 2014-06-30 at 11:54 +0530, Preeti U Murthy wrote:

Commit 8d6f7c5a: "powerpc/powernv: Make it possible to skip the IRQHAPPENED
check in power7_nap()" added code that prevents even cores which enter sleep
on idle, from checking for pending interrupts. Fix this.

To be clear, it is a bug in the original commit. Mikey and I pair programmed
that code, and he was *definitely* typing at that point ;)

Can you please include in the changelog what the symptom of the bug is, and
have you seen it in practice?

The bad commit went into 3.16-rc1, so we don't need to backport this to any
stable release.

cheers

On Tue, 2014-07-01 at 10:52 +1000, Michael Ellerman wrote:

On Mon, 2014-06-30 at 11:54 +0530, Preeti U Murthy wrote:

quoted

Commit 8d6f7c5a: "powerpc/powernv: Make it possible to skip the IRQHAPP=

ENED

quoted

check in power7_nap()" added code that prevents even cores which enter =

sleep

quoted

on idle, from checking for pending interrupts. Fix this.

=20
To be clear, it is a bug in the original commit. Mikey and I pair program=

med

that code, and he was *definitely* typing at that point ;)

It's always nice to know that in battle a comrade will throw himself on
a grenade to save you. :-P

Actually, I'm pretty sure this happened when you were away (probably on
a beach somewhere), I was forward porting the patch set, hit a conflict
and fucked it up. =20

Mikey

=20
Can you please include in the changelog what the symptom of the bug is, a=

nd

have you seen it in practice?
=20
The bad commit went into 3.16-rc1, so we don't need to backport this to a=

ny

stable release.
=20
cheers
=20

quoted

diff --git a/arch/powerpc/kernel/idle_power7.S b/arch/powerpc/kernel/id=

le_power7.S

quoted

index 2480256..5cf3d36 100644

--- a/arch/powerpc/kernel/idle_power7.S
+++ b/arch/powerpc/kernel/idle_power7.S

@@ -131,7 +131,7 @@ _GLOBAL(power7_nap)

=20
 _GLOBAL(power7_sleep)
 	li	r3,1
-	li	r4,0
+	li	r4,1
 	b	power7_powersave_common
 	/* No return */
=20
=20

=20
=20
=20
=20
=20