From: Ben Hutchings Date: Tue, 7 Sep 2010 01:28:56 +0000 (-0700) Subject: 3c59x: Fix deadlock in vortex_error() X-Git-Tag: v2.6.36-rc4~6^2~17 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=89b12faba4f3441c9457c5278851e8a93ffd008d;p=platform%2Fkernel%2Flinux-exynos.git 3c59x: Fix deadlock in vortex_error() This fixes a bug introduced in commit de847272149365363a6043a963a6f42fb91566e2 "3c59x: Use fine-grained locks for MII and windowed register access". vortex_interrupt() holds vp->window_lock over multiple register accesses to reduce locking overhead. However it also needs to call vortex_error() sometimes, and that uses the regular functions for access to windowed registers, which will try to acquire window_lock again. Therefore, drop window_lock around the call to vortex_error() and set the window afterward reacquiring the lock. Since vortex_error() may call vortex_rx(), which *does* require its caller to hold window_lock, lift that call up into vortex_interrupt(). This also removes the potential for calling vortex_rx() on a later-generation NIC. Reported-and-tested-by: Jens Schüßler [in Debian's 2.6.32] Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller --- diff --git a/drivers/net/3c59x.c b/drivers/net/3c59x.c index a045559..85671ad 100644 --- a/drivers/net/3c59x.c +++ b/drivers/net/3c59x.c @@ -1994,10 +1994,9 @@ vortex_error(struct net_device *dev, int status) } } - if (status & RxEarly) { /* Rx early is unused. */ - vortex_rx(dev); + if (status & RxEarly) /* Rx early is unused. */ iowrite16(AckIntr | RxEarly, ioaddr + EL3_CMD); - } + if (status & StatsFull) { /* Empty statistics. */ static int DoneDidThat; if (vortex_debug > 4) @@ -2298,7 +2297,12 @@ vortex_interrupt(int irq, void *dev_id) if (status & (HostError | RxEarly | StatsFull | TxComplete | IntReq)) { if (status == 0xffff) break; + if (status & RxEarly) + vortex_rx(dev); + spin_unlock(&vp->window_lock); vortex_error(dev, status); + spin_lock(&vp->window_lock); + window_set(vp, 7); } if (--work_done < 0) {