[PATCH net-next 1/2] pcnet32: stop holding device spin lock during napi_complete_done

[Oscar Maes <oscmaes92@gmail.com>]

napi_complete_done may call gro_flush_normal (though not currently, as GRO
is unsupported at the moment), which may result in packet TX. This will
eventually result in calling pcnet32_start_xmit - resulting in a deadlock
while trying to re-acquire the already locked spin lock.

Signed-off-by: Oscar Maes <oscmaes92@gmail.com>
---
 drivers/net/ethernet/amd/pcnet32.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/amd/pcnet32.c b/drivers/net/ethernet/amd/pcnet32.c
index 911808ab13a7..4f3076d4ea34 100644
--- a/drivers/net/ethernet/amd/pcnet32.c
+++ b/drivers/net/ethernet/amd/pcnet32.c
@@ -1407,8 +1407,10 @@ static int pcnet32_poll(struct napi_struct *napi, int budget)
 		pcnet32_restart(dev, CSR0_START);
 		netif_wake_queue(dev);
 	}
+	spin_unlock_irqrestore(&lp->lock, flags);
 
 	if (work_done < budget && napi_complete_done(napi, work_done)) {
+		spin_lock_irqsave(&lp->lock, flags);
 		/* clear interrupt masks */
 		val = lp->a->read_csr(ioaddr, CSR3);
 		val &= 0x00ff;
@@ -1416,9 +1418,9 @@ static int pcnet32_poll(struct napi_struct *napi, int budget)
 
 		/* Set interrupt enable. */
 		lp->a->write_csr(ioaddr, CSR0, CSR0_INTEN);
+		spin_unlock_irqrestore(&lp->lock, flags);
 	}
 
-	spin_unlock_irqrestore(&lp->lock, flags);
 	return work_done;
 }
 
-- 
2.39.5