projects / people / pmueller / ipfire-2.x.git / blame
| Commit | Line | Data |
|---|---|---|
| 2cb7cef9 BS |
1 | From: Gerald Schaefer <geraldsc@de.ibm.com> |
| 2 | Subject: cio: Properly disable not operational subchannel. | |
| 3 | References: bnc#477666,LTC#51619 | |
| 4 | ||
| 5 | Symptom: Kernel BUG at drivers/s390/cio/device_fsm.c:1241! | |
| 6 | Problem: After deferred cc=3 was received on all paths, a | |
| 7 | device was set to not operational to prepare for | |
| 8 | re-evaluation. An unsolicited interrupt indicating | |
| 9 | that the device became accessible again triggered | |
| 10 | an invalid event in the state machine (interrupt in | |
| 11 | not operational state). | |
| 12 | Solution: Properly disable the subchannel before setting the | |
| 13 | device not operational. To be able to disable the | |
| 14 | subchannel reliably, pending status needs to be | |
| 15 | collected. | |
| 16 | ||
| 17 | Acked-by: John Jolly <jjolly@suse.de> | |
| 18 | ||
| 19 | --- | |
| 20 | drivers/s390/cio/cio.c | 19 +++++-------------- | |
| 21 | drivers/s390/cio/device_fsm.c | 4 ++-- | |
| 22 | 2 files changed, 7 insertions(+), 16 deletions(-) | |
| 23 | ||
| 24 | Index: linux-sles11/drivers/s390/cio/device_fsm.c | |
| 25 | =================================================================== | |
| 26 | --- linux-sles11.orig/drivers/s390/cio/device_fsm.c | |
| 27 | +++ linux-sles11/drivers/s390/cio/device_fsm.c | |
| 28 | @@ -726,7 +726,7 @@ static void ccw_device_generic_notoper(s | |
| 29 | { | |
| 30 | struct subchannel *sch; | |
| 31 | ||
| 32 | - cdev->private->state = DEV_STATE_NOT_OPER; | |
| 33 | + ccw_device_set_notoper(cdev); | |
| 34 | sch = to_subchannel(cdev->dev.parent); | |
| 35 | css_schedule_eval(sch->schid); | |
| 36 | } | |
| 37 | @@ -1048,7 +1048,7 @@ ccw_device_offline_irq(struct ccw_device | |
| 38 | sch = to_subchannel(cdev->dev.parent); | |
| 39 | /* | |
| 40 | * An interrupt in state offline means a previous disable was not | |
| 41 | - * successful. Try again. | |
| 42 | + * successful - should not happen, but we try to disable again. | |
| 43 | */ | |
| 44 | cio_disable_subchannel(sch); | |
| 45 | } | |
| 46 | Index: linux-sles11/drivers/s390/cio/cio.c | |
| 47 | =================================================================== | |
| 48 | --- linux-sles11.orig/drivers/s390/cio/cio.c | |
| 49 | +++ linux-sles11/drivers/s390/cio/cio.c | |
| 50 | @@ -464,25 +464,16 @@ int cio_disable_subchannel(struct subcha | |
| 51 | if (ccode == 3) /* Not operational. */ | |
| 52 | return -ENODEV; | |
| 53 | ||
| 54 | - if (scsw_actl(&sch->schib.scsw) != 0) | |
| 55 | - /* | |
| 56 | - * the disable function must not be called while there are | |
| 57 | - * requests pending for completion ! | |
| 58 | - */ | |
| 59 | - return -EBUSY; | |
| 60 | - | |
| 61 | for (retry = 5, ret = 0; retry > 0; retry--) { | |
| 62 | sch->schib.pmcw.ena = 0; | |
| 63 | ret = cio_modify(sch); | |
| 64 | if (ret == -ENODEV) | |
| 65 | break; | |
| 66 | - if (ret == -EBUSY) | |
| 67 | - /* | |
| 68 | - * The subchannel is busy or status pending. | |
| 69 | - * We'll disable when the next interrupt was delivered | |
| 70 | - * via the state machine. | |
| 71 | - */ | |
| 72 | - break; | |
| 73 | + if (ret == -EBUSY) { | |
| 74 | + struct irb irb; | |
| 75 | + if (tsch(sch->schid, &irb) != 0) | |
| 76 | + break; | |
| 77 | + } | |
| 78 | if (ret == 0) { | |
| 79 | stsch (sch->schid, &sch->schib); | |
| 80 | if (!sch->schib.pmcw.ena) |