From: Anton Ivanov anton.ivanov@cambridgegreys.com
commit d848074b2f1eb11a38691285f7366bce83087014 upstream.
Fixes crashes due to ubd requeue logic conflicting with the block-mq logic. Crash is reproducible in 5.0 - 5.3.
Fixes: 53766defb8c8 ("um: Clean-up command processing in UML UBD driver") Cc: stable@vger.kernel.org # v5.0+ Signed-off-by: Anton Ivanov anton.ivanov@cambridgegreys.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/um/drivers/ubd_kern.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
--- a/arch/um/drivers/ubd_kern.c +++ b/arch/um/drivers/ubd_kern.c @@ -1403,8 +1403,12 @@ static blk_status_t ubd_queue_rq(struct
spin_unlock_irq(&ubd_dev->lock);
- if (ret < 0) - blk_mq_requeue_request(req, true); + if (ret < 0) { + if (ret == -ENOMEM) + res = BLK_STS_RESOURCE; + else + res = BLK_STS_DEV_RESOURCE; + }
return res; }