From: Sebastian Ott Date: Wed, 5 Sep 2012 12:19:42 +0000 (+0200) Subject: s390/cio: fix IO subchannel event race X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=43d0be75af8d05654b88d1da494cf292714fbdec;p=deliverable%2Flinux.git s390/cio: fix IO subchannel event race If the subchannel event function is called from IRQ context and we observe that the subchannel in question is gone we flag the attached device as not operational and schedule the event function to be called again from process context where the subchannel gets deregistered. However if the subchannel reappeared at the time the event function gets called from process context we would do nothing and leave the device in not operational state. Recognize this case in sch_get_action and trigger reexamination of the subchannel/device. Acked-by: Peter Oberparleiter Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky --- diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c index ed25c8740a9c..e8e1a108cdf8 100644 --- a/drivers/s390/cio/device.c +++ b/drivers/s390/cio/device.c @@ -1426,6 +1426,8 @@ static enum io_sch_action sch_get_action(struct subchannel *sch) return IO_SCH_REPROBE; if (cdev->online) return IO_SCH_VERIFY; + if (cdev->private->state == DEV_STATE_NOT_OPER) + return IO_SCH_UNREG_ATTACH; return IO_SCH_NOP; }