[PATCH] Fix ppc64 smu driver locking

The SMU driver has a small mistake in the locking of the interrupt code,
if polled access and interrupt access race, interrupt may take a lock
and return without releasing it. This fixes it. With that patch, the
driver is rock solid with my experimental thermal control (which bangs
it pretty hard) racing with real time clock and cpufreq handling.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Benjamin Herrenschmidt 2005-09-30 08:25:17 +10:00 committed by Linus Torvalds
parent 7644143cd6
commit a44fe13eab

View file

@ -153,8 +153,10 @@ static irqreturn_t smu_db_intr(int irq, void *arg, struct pt_regs *regs)
spin_lock_irqsave(&smu->lock, flags);
gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
if ((gpio & 7) != 7)
if ((gpio & 7) != 7) {
spin_unlock_irqrestore(&smu->lock, flags);
return IRQ_HANDLED;
}
cmd = smu->cmd_cur;
smu->cmd_cur = NULL;