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author | Ben Hutchings <ben@decadent.org.uk> | 2010-09-06 18:28:56 -0700 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2010-09-07 13:57:22 -0700 |
commit | 89b12faba4f3441c9457c5278851e8a93ffd008d (patch) | |
tree | fa7af4864a3200a7abcadea2a04886515249d326 | |
parent | 1ee89bd0fe72e381c8e4ef887d53c19c8adc6c93 (diff) | |
download | talos-obmc-linux-89b12faba4f3441c9457c5278851e8a93ffd008d.tar.gz talos-obmc-linux-89b12faba4f3441c9457c5278851e8a93ffd008d.zip |
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 <jgs@trash.net> [in Debian's 2.6.32]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | drivers/net/3c59x.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/net/3c59x.c b/drivers/net/3c59x.c index a045559c81cf..85671adae455 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) { |