sata_mv: fix MSI irq race condition

Fix a (rare) race condition in mv_interrupt() when using MSI.

The value of hpriv->main_irq_mask_addr can change on on the fly,
and without this patch we could end up writing back a stale copy
to the hardware.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This commit is contained in:
Mark Lord 2009-03-10 16:28:51 -04:00 committed by Jeff Garzik
parent 041b62374c
commit 9d51af7bd2

View File

@ -2218,12 +2218,13 @@ static irqreturn_t mv_interrupt(int irq, void *dev_instance)
else
handled = mv_host_intr(host, pending_irqs);
}
spin_unlock(&host->lock);
/* for MSI: unmask; interrupt cause bits will retrigger now */
if (using_msi)
writel(hpriv->main_irq_mask, hpriv->main_irq_mask_addr);
spin_unlock(&host->lock);
return IRQ_RETVAL(handled);
}