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* RE: [PATCH] x86_64 ioapic: check_timer_pin Don't add_pin_to_irq if it is already there.
@ 2007-01-08 22:56 Lu, Yinghai
  0 siblings, 0 replies; 2+ messages in thread
From: Lu, Yinghai @ 2007-01-08 22:56 UTC (permalink / raw)
  To: ebiederm, Andrew Morton
  Cc: Linus Torvalds, Tobias Diedrich, Adrian Bunk, Andi Kleen,
	Linux Kernel Mailing List

-----Original Message-----
From: ebiederm@xmission.com [mailto:ebiederm@xmission.com] 
Sent: Monday, January 08, 2007 2:50 PM
To: Andrew Morton
Cc: Linus Torvalds; Tobias Diedrich; Adrian Bunk; Andi Kleen; Linux
Kernel Mailing List; Lu, Yinghai
Subject: [PATCH] x86_64 ioapic: check_timer_pin Don't add_pin_to_irq if
it is already there.

>Yep.  My oversight.  Here is the trivial patch to fix it.  I don't
>see how we could hit this case but if we are going to allow for it
>we should handle it correctly.

Yes, in your check_timer calling sequence, at that point irq can not be
0.
( remove_irq_to_pin already remove that entry).

Or in check_timer_pin

+	if ((irq != -1) && (irq != 0)) {

==>

+	if (irq != -1) {

YH




^ permalink raw reply	[flat|nested] 2+ messages in thread

* [PATCH] x86_64 ioapic: check_timer_pin Don't add_pin_to_irq if it is already there.
  2007-01-08 21:46 [PATCH 1/4] x86_64 io_apic: Implement remove_pin_to_irq Lu, Yinghai
@ 2007-01-08 22:50 ` Eric W. Biederman
  0 siblings, 0 replies; 2+ messages in thread
From: Eric W. Biederman @ 2007-01-08 22:50 UTC (permalink / raw)
  To: Andrew Morton
  Cc: Linus Torvalds, Tobias Diedrich, Adrian Bunk, Andi Kleen,
	Linux Kernel Mailing List, Lu, Yinghai

"Lu, Yinghai" <yinghai.lu@amd.com> writes:

>>Any updates to add_pin_to_irq are wrong.  It works fine.  If there
>>is something wrong we need to fix remove_pin_to_irq.
>
>>What is the problem you see?  Sorry I'm dense at the moment.

> In the check_timer_pin, irq_from_pin could return 0, it mean some entry
> is for IRQ0 already.
> The add_pin_to_irq could add another same entry for it again.

Yep.  My oversight.  Here is the trivial patch to fix it.  I don't
see how we could hit this case but if we are going to allow for it
we should handle it correctly.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
 arch/x86_64/kernel/io_apic.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/arch/x86_64/kernel/io_apic.c b/arch/x86_64/kernel/io_apic.c
index 4891959..cc8e9a4 100644
--- a/arch/x86_64/kernel/io_apic.c
+++ b/arch/x86_64/kernel/io_apic.c
@@ -1687,7 +1687,8 @@ static int check_timer_pin(int apic, int pin)
 	idx = update_irq0_entry(apic, pin);
 
 	/* Add an entry in irq_to_pin */
-	add_pin_to_irq(0, apic, pin);
+	if (irq != 0)
+		add_pin_to_irq(0, apic, pin);
 
 	/* Now setup the irq */
 	setup_IO_APIC_irq(apic, pin, idx, 0);
-- 
1.4.4.1.g278f



^ permalink raw reply	[flat|nested] 2+ messages in thread

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Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
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2007-01-08 22:56 [PATCH] x86_64 ioapic: check_timer_pin Don't add_pin_to_irq if it is already there Lu, Yinghai
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2007-01-08 21:46 [PATCH 1/4] x86_64 io_apic: Implement remove_pin_to_irq Lu, Yinghai
2007-01-08 22:50 ` [PATCH] x86_64 ioapic: check_timer_pin Don't add_pin_to_irq if it is already there Eric W. Biederman

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