Re: [PATCH 2/3] HPET: Enter hpet_interrupt_handler with interrupts disabled

["Matt Fleming" <mjf@gentoo.org>]

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2008/11/2 Will Newton <will.newton@gmail.com>:
>
> Combining IRQF_DISABLED and IRQF_SHARED does not reliably disable
> interrupts in the handler. Perhaps IRQF_SHARED should be removed at
> the same time?
>

I didn't know that. Under what conditions is it unreliable?

I've attached a second attempt at this patch. It seems that the IRQ is
never shared anyway, so I followed your suggestion and removed
IRQF_SHARED. My machine seems to be running fine.

>From c445728f36de599770088e345fc03ef9fafd8470 Mon Sep 17 00:00:00 2001
From: Matt Fleming <mjf@gentoo.org>
Date: Sun, 2 Nov 2008 14:00:23 +0000
Subject: [PATCH 2/3] HPET: Enter hpet_interrupt_handler with interrupts disabled

Some functions that may be called from this handler require that
interrupts are disabled. Also, combining IRQF_DISABLED and
IRQF_SHARED does not reliably disable interrupts in a handler, so
remove IRQF_SHARED from the irq flags (this irq is not shared anyway).

Signed-off-by: Matt Fleming <mjf@gentoo.org>
---
 arch/x86/kernel/hpet.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index f10f946..bfb17f4 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -445,7 +445,7 @@ static int hpet_setup_irq(struct hpet_dev *dev)
 {

        if (request_irq(dev->irq, hpet_interrupt_handler,
-                       IRQF_SHARED|IRQF_NOBALANCING, dev->name, dev))
+                       IRQF_DISABLED|IRQF_NOBALANCING, dev->name, dev))
                return -1;

        disable_irq(dev->irq);
--
1.5.6.4

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From c445728f36de599770088e345fc03ef9fafd8470 Mon Sep 17 00:00:00 2001
From: Matt Fleming <mjf@gentoo.org>
Date: Sun, 2 Nov 2008 14:00:23 +0000
Subject: [PATCH 2/3] HPET: Enter hpet_interrupt_handler with interrupts disabled

Some functions that may be called from this handler require that
interrupts are disabled. Also, combining IRQF_DISABLED and
IRQF_SHARED does not reliably disable interrupts in a handler, so
remove IRQF_SHARED from the irq flags (this irq is not shared anyway).

Signed-off-by: Matt Fleming <mjf@gentoo.org>
---
 arch/x86/kernel/hpet.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index f10f946..bfb17f4 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -445,7 +445,7 @@ static int hpet_setup_irq(struct hpet_dev *dev)
 {
 
 	if (request_irq(dev->irq, hpet_interrupt_handler,
-			IRQF_SHARED|IRQF_NOBALANCING, dev->name, dev))
+			IRQF_DISABLED|IRQF_NOBALANCING, dev->name, dev))
 		return -1;
 
 	disable_irq(dev->irq);
-- 
1.5.6.4