This is a note to let you know that I've just added the patch titled
genirq: Avoid deadlock in spurious handling
to the 3.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
genirq-avoid-deadlock-in-spurious-handling.patch
and it can be found in the queue-3.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.
>From e716efde75267eab919cdb2bef5b2cb77f305326 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <[email protected]>
Date: Fri, 23 Nov 2012 10:08:44 +0100
Subject: genirq: Avoid deadlock in spurious handling
From: Thomas Gleixner <[email protected]>
commit e716efde75267eab919cdb2bef5b2cb77f305326 upstream.
commit 52553ddf(genirq: fix regression in irqfixup, irqpoll)
introduced a potential deadlock by calling the action handler with the
irq descriptor lock held.
Remove the call and let the handling code run even for an interrupt
where only a single action is registered. That matches the goal of
the above commit and avoids the deadlock.
Document the confusing action = desc->action reload in the handling
loop while at it.
Reported-and-tested-by: "Wang, Warner" <[email protected]>
Tested-by: Edward Donovan <[email protected]>
Cc: "Wang, Song-Bo (Stoney)" <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
kernel/irq/spurious.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -80,13 +80,11 @@ static int try_one_irq(int irq, struct i
/*
* All handlers must agree on IRQF_SHARED, so we test just the
- * first. Check for action->next as well.
+ * first.
*/
action = desc->action;
if (!action || !(action->flags & IRQF_SHARED) ||
- (action->flags & __IRQF_TIMER) ||
- (action->handler(irq, action->dev_id) == IRQ_HANDLED) ||
- !action->next)
+ (action->flags & __IRQF_TIMER))
goto out;
/* Already running on another processor */
@@ -104,6 +102,7 @@ static int try_one_irq(int irq, struct i
do {
if (handle_irq_event(desc) == IRQ_HANDLED)
ret = IRQ_HANDLED;
+ /* Make sure that there is still a valid action */
action = desc->action;
} while ((desc->istate & IRQS_PENDING) && action);
desc->istate &= ~IRQS_POLL_INPROGRESS;
Patches currently in stable-queue which might be from [email protected] are
queue-3.0/genirq-avoid-deadlock-in-spurious-handling.patch
queue-3.0/posix-cpu-timers-fix-nanosleep-task_struct-leak.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
