genirq: Avoid deadlock in spurious handling
authorThomas Gleixner <tglx@linutronix.de>
Fri, 23 Nov 2012 09:08:44 +0000 (10:08 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 28 Feb 2013 14:58:58 +0000 (06:58 -0800)
commitb3c57f009cfd9ed81737169c4026bfd03191d993
tree73ae8bf6b8258783eb608f18f4c984d36c2a6fcf
parent526a26556b9069238ea7eecb9095cc672daef0e5
genirq: Avoid deadlock in spurious handling

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" <warner.wang@hp.com>
Tested-by: Edward Donovan <edward.donovan@numble.net>
Cc: "Wang, Song-Bo (Stoney)" <song-bo.wang@hp.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernel/irq/spurious.c