Reviewed-by: Wang ShaoBo <bobo.shaobowang@huawei.com> 在 2021/10/28 22:42, Chen Silong 写道:

From: Eric Farman <farman@linux.ibm.com>

stable inclusion from stable-v5.10.44 commit cad3dc73c0645d00adfe96cebc8d950897cc1227 bugzilla:https://bugzilla.openeuler.org/show_bug.cgi?id=453 CVE: NA

-------------------------------------------------

[ Upstream commit 6c02ac4c9211edabe17bda437ac97e578756f31b ]

When an I/O request is made, the fsm_io_request() routine moves the FSM state from IDLE to CP_PROCESSING, and then fsm_io_helper() moves it to CP_PENDING if the START SUBCHANNEL received a cc0. Yet, the error case to go from CP_PROCESSING back to IDLE is done after the FSM call returns.

Let's move this up into the FSM proper, to provide some better symmetry when unwinding in this case.

Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Acked-by: Matthew Rosato <mjrosato@linux.ibm.com> Message-Id: <20210511195631.3995081-3-farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Chen Silong <2019117735@my.swjtu.edu.cn> --- drivers/s390/cio/vfio_ccw_fsm.c | 1 + drivers/s390/cio/vfio_ccw_ops.c | 2 -- 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_fsm.c b/drivers/s390/cio/vfio_ccw_fsm.c index 23e61aa638e4..e435a9cd92da 100644 --- a/drivers/s390/cio/vfio_ccw_fsm.c +++ b/drivers/s390/cio/vfio_ccw_fsm.c @@ -318,6 +318,7 @@ static void fsm_io_request(struct vfio_ccw_private *private, }

err_out: + private->state = VFIO_CCW_STATE_IDLE; trace_vfio_ccw_fsm_io_request(scsw->cmd.fctl, schid, io_region->ret_code, errstr); } diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c index 1ad5f7018ec2..2280f51dd679 100644 --- a/drivers/s390/cio/vfio_ccw_ops.c +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -276,8 +276,6 @@ static ssize_t vfio_ccw_mdev_write_io_region(struct vfio_ccw_private *private, }

vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_IO_REQ); - if (region->ret_code != 0) - private->state = VFIO_CCW_STATE_IDLE; ret = (region->ret_code != 0) ? region->ret_code : count;

out_unlock: