tg3: tg3_timer() should grab tp->lock before checking for tp->irq_sync

This is to avoid the race between tg3_timer() and the execution paths
which does not invoke tg3_timer_stop() and releases tp->lock before
calling synchronize_irq()

Reported-by: Peter Hurley <[email protected]>
Tested-by: Peter Hurley <[email protected]>
Signed-off-by: Prashant Sreedharan <[email protected]>
Signed-off-by: Michael Chan <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 553dcd8a9df29f64108285c1f520635e287f7ca8..2dbd4aea01f3ba8f9b09852a2c0ec5fbfcead6d3 100644 (file)
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -10903,11 +10903,13 @@ static void tg3_timer(unsigned long __opaque)
 {
        struct tg3 *tp = (struct tg3 *) __opaque;
 
-       if (tp->irq_sync || tg3_flag(tp, RESET_TASK_PENDING))
-               goto restart_timer;
-
        spin_lock(&tp->lock);
 
+       if (tp->irq_sync || tg3_flag(tp, RESET_TASK_PENDING)) {
+               spin_unlock(&tp->lock);
+               goto restart_timer;
+       }
+
        if (tg3_asic_rev(tp) == ASIC_REV_5717 ||
            tg3_flag(tp, 57765_CLASS))
                tg3_chk_missed_msi(tp);