[patch 19/21] dasd: fix message flood for unsolicited interrupts

From: Martin Schwidefsky
Date: Wed Oct 01 2008 - 04:59:29 EST


From: Stefan Haberland <stefan.haberland@xxxxxxxxxx>

In the unsolicited interupt handler fake IRBs from CIO have to be
ignored because there is nothing to do.
The function dump_sense should not be called if there is no sense
data available.

Signed-off-by: Stefan Haberland <stefan.haberland@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
---

drivers/s390/block/dasd_eckd.c | 25 ++++++++++++++++++++-----
1 file changed, 20 insertions(+), 5 deletions(-)

Index: quilt-2.6/drivers/s390/block/dasd_eckd.c
===================================================================
--- quilt-2.6.orig/drivers/s390/block/dasd_eckd.c
+++ quilt-2.6/drivers/s390/block/dasd_eckd.c
@@ -1501,12 +1501,27 @@ static void dasd_eckd_handle_unsolicited
return;
}

- /* just report other unsolicited interrupts */
- DEV_MESSAGE(KERN_DEBUG, device, "%s",
- "unsolicited interrupt received");
- device->discipline->dump_sense(device, NULL, irb);
- dasd_schedule_device_bh(device);
+ if ((irb->scsw.cmd.cc == 1) &&
+ (irb->scsw.cmd.fctl & SCSW_FCTL_START_FUNC) &&
+ (irb->scsw.cmd.actl & SCSW_ACTL_START_PEND) &&
+ (irb->scsw.cmd.stctl & SCSW_STCTL_STATUS_PEND)) {
+ /* fake irb do nothing, they are handled elsewhere */
+ dasd_schedule_device_bh(device);
+ return;
+ }

+ if (!(irb->esw.esw0.erw.cons)) {
+ /* just report other unsolicited interrupts */
+ DEV_MESSAGE(KERN_ERR, device, "%s",
+ "unsolicited interrupt received");
+ } else {
+ DEV_MESSAGE(KERN_ERR, device, "%s",
+ "unsolicited interrupt received "
+ "(sense available)");
+ device->discipline->dump_sense(device, NULL, irb);
+ }
+
+ dasd_schedule_device_bh(device);
return;
};


--
blue skies,
Martin.

"Reality continues to ruin my life." - Calvin.

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