lcs: Channel errors drive lcs_recovery which leads to kernel panic.

When the lcs irq routine detects channel failures it drives device recovery.
After this event the device is no longer usable for shutdown requests,
because the lcs_irq routine may get wrong channel status information.
In such a case the lcs_irq routine marks the channel in 'error' state.
The channel state comes back to 'running' after restarting the channels.

Signed-off-by: Klaus D. Wacker <kdwacker@de.ibm.com>
Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

diff --git a/drivers/s390/net/lcs.c b/drivers/s390/net/lcs.c
index e4b11afbbc9fcce73a60c75b579e581d7ff14930..0fd663b23d767c9a6e81777d51df467af90631e6 100644 (file)
--- a/drivers/s390/net/lcs.c
+++ b/drivers/s390/net/lcs.c
@@ -1400,11 +1400,14 @@ lcs_irq(struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
                PRINT_WARN("check on device %s, dstat=0x%X, cstat=0x%X \n",
                            cdev->dev.bus_id, dstat, cstat);
                if (rc) {
-                       lcs_schedule_recovery(card);
-                       wake_up(&card->wait_q);
-                       return;
+                       channel->state = LCS_CH_STATE_ERROR;
                }
        }
+       if (channel->state == LCS_CH_STATE_ERROR) {
+               lcs_schedule_recovery(card);
+               wake_up(&card->wait_q);
+               return;
+       }
        /* How far in the ccw chain have we processed? */
        if ((channel->state != LCS_CH_STATE_INIT) &&
            (irb->scsw.fctl & SCSW_FCTL_START_FUNC)) {
@@ -1708,6 +1711,8 @@ lcs_stopcard(struct lcs_card *card)
 
        if (card->read.state != LCS_CH_STATE_STOPPED &&
            card->write.state != LCS_CH_STATE_STOPPED &&
+           card->read.state != LCS_CH_STATE_ERROR &&
+           card->write.state != LCS_CH_STATE_ERROR &&
            card->state == DEV_STATE_UP) {
                lcs_clear_multicast_list(card);
                rc = lcs_send_stoplan(card,LCS_INITIATOR_TCPIP);

diff --git a/drivers/s390/net/lcs.h b/drivers/s390/net/lcs.h
index 0e1e4a0a88f04fac497d5d280f7329d47821f824..8976fb0b070a73944b102da520ca4f691461587f 100644 (file)
--- a/drivers/s390/net/lcs.h
+++ b/drivers/s390/net/lcs.h
@@ -138,6 +138,7 @@ enum lcs_channel_states {
        LCS_CH_STATE_RUNNING,
        LCS_CH_STATE_SUSPENDED,
        LCS_CH_STATE_CLEARED,
+       LCS_CH_STATE_ERROR,
 };
 
 /**