Hello Linus, please pull s390 changes for 5.13-rc4. Thank you, Vasily The following changes since commit 6efb943b8616ec53a5e444193dccf1af9ad627b5: Linux 5.13-rc1 (2021-05-09 14:17:44 -0700) are available in the Git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git tags/s390-5.13-3 for you to fetch changes up to ffa99c436aa70c0c0980866523a6ae1023c96768: Merge tag 'vfio-ccw-20210520' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/vfio-ccw into fixes (2021-05-26 23:46:34 +0200) ---------------------------------------------------------------- - Fix races in vfio-ccw request handling. ---------------------------------------------------------------- Eric Farman (3): vfio-ccw: Check initialized flag in cp_init() vfio-ccw: Reset FSM state to IDLE inside FSM vfio-ccw: Serialize FSM IDLE state with I/O completion Vasily Gorbik (1): Merge tag 'vfio-ccw-20210520' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/vfio-ccw into fixes drivers/s390/cio/vfio_ccw_cp.c | 4 ++++ drivers/s390/cio/vfio_ccw_drv.c | 12 ++++++++++-- drivers/s390/cio/vfio_ccw_fsm.c | 1 + drivers/s390/cio/vfio_ccw_ops.c | 2 -- 4 files changed, 15 insertions(+), 4 deletions(-) diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c index b9febc581b1f..8d1b2771c1aa 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -638,6 +638,10 @@ int cp_init(struct channel_program *cp, struct device *mdev, union orb *orb) static DEFINE_RATELIMIT_STATE(ratelimit_state, 5 * HZ, 1); int ret; + /* this is an error in the caller */ + if (cp->initialized) + return -EBUSY; + /* * We only support prefetching the channel program. We assume all channel * programs executed by supported guests likewise support prefetching. diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c index 8c625b530035..9b61e9b131ad 100644 --- a/drivers/s390/cio/vfio_ccw_drv.c +++ b/drivers/s390/cio/vfio_ccw_drv.c @@ -86,6 +86,7 @@ static void vfio_ccw_sch_io_todo(struct work_struct *work) struct vfio_ccw_private *private; struct irb *irb; bool is_final; + bool cp_is_finished = false; private = container_of(work, struct vfio_ccw_private, io_work); irb = &private->irb; @@ -94,14 +95,21 @@ static void vfio_ccw_sch_io_todo(struct work_struct *work) (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT)); if (scsw_is_solicited(&irb->scsw)) { cp_update_scsw(&private->cp, &irb->scsw); - if (is_final && private->state == VFIO_CCW_STATE_CP_PENDING) + if (is_final && private->state == VFIO_CCW_STATE_CP_PENDING) { cp_free(&private->cp); + cp_is_finished = true; + } } mutex_lock(&private->io_mutex); memcpy(private->io_region->irb_area, irb, sizeof(*irb)); mutex_unlock(&private->io_mutex); - if (private->mdev && is_final) + /* + * Reset to IDLE only if processing of a channel program + * has finished. Do not overwrite a possible processing + * state if the final interrupt was for HSCH or CSCH. + */ + if (private->mdev && cp_is_finished) private->state = VFIO_CCW_STATE_IDLE; if (private->io_trigger) 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 491a64c61fff..c57d2a7f0919 100644 --- a/drivers/s390/cio/vfio_ccw_ops.c +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -279,8 +279,6 @@ 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:
