If we get 0xffff back when reading the status register, assume the card

has gone away instead of spinning in the interrupt handler.  This stops
my machine from hanging when I eject a rl(4)-based cardbus card.

Reviewed by:	imp

1 files changed, 5 insertions, 0 deletions

diff --git a/sys/pci/if_rl.c b/sys/pci/if_rl.c
index 4ffe7a3..e5dc0be 100644
--- a/sys/pci/if_rl.c
+++ b/sys/pci/if_rl.c
@@ -1380,6 +1380,8 @@ rl_poll (struct ifnet *ifp, enum poll_cmd cmd, int count)
 		u_int16_t       status;
 
 		status = CSR_READ_2(sc, RL_ISR);
+		if (status == 0xffff)
+			goto done;
 		if (status)
 			CSR_WRITE_2(sc, RL_ISR, status);
 
@@ -1426,6 +1428,9 @@ static void rl_intr(arg)
 	for (;;) {
 
 		status = CSR_READ_2(sc, RL_ISR);
+		/* If the card has gone away the read returns 0xffff. */
+		if (status == 0xffff)
+			break;
 		if (status)
 			CSR_WRITE_2(sc, RL_ISR, status);