From cffcc109fd682075dee79bade3d60a07152a8fd1 Mon Sep 17 00:00:00 2001 From: Eric Farman Date: Thu, 7 Jul 2022 15:57:29 +0200 Subject: vfio/ccw: Do not change FSM state in subchannel event The routine vfio_ccw_sch_event() is tasked with handling subchannel events, specifically machine checks, on behalf of vfio-ccw. It correctly calls cio_update_schib(), and if that fails (meaning the subchannel is gone) it makes an FSM event call to mark the subchannel Not Operational. If that worked, however, then it decides that if the FSM state was already Not Operational (implying the subchannel just came back), then it should simply change the FSM to partially- or fully-open. Remove this trickery, since a subchannel returning will require more probing than simply "oh all is well again" to ensure it works correctly. Fixes: bbe37e4cb8970 ("vfio: ccw: introduce a finite state machine") Signed-off-by: Eric Farman Reviewed-by: Matthew Rosato Link: https://lore.kernel.org/r/20220707135737.720765-4-farman@linux.ibm.com Signed-off-by: Alex Williamson --- drivers/s390/cio/vfio_ccw_drv.c | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-) (limited to 'drivers/s390/cio/vfio_ccw_drv.c') diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c index 179eb614fa5b..279ad2161f17 100644 --- a/drivers/s390/cio/vfio_ccw_drv.c +++ b/drivers/s390/cio/vfio_ccw_drv.c @@ -301,19 +301,11 @@ static int vfio_ccw_sch_event(struct subchannel *sch, int process) if (work_pending(&sch->todo_work)) goto out_unlock; - if (cio_update_schib(sch)) { - vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_NOT_OPER); - rc = 0; - goto out_unlock; - } - - private = dev_get_drvdata(&sch->dev); - if (private->state == VFIO_CCW_STATE_NOT_OPER) { - private->state = private->mdev ? VFIO_CCW_STATE_IDLE : - VFIO_CCW_STATE_STANDBY; - } rc = 0; + if (cio_update_schib(sch)) + vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_NOT_OPER); + out_unlock: spin_unlock_irqrestore(sch->lock, flags); -- cgit v1.2.3-59-g8ed1b