From d848074b2f1eb11a38691285f7366bce83087014 Mon Sep 17 00:00:00 2001 From: Anton Ivanov Date: Tue, 29 Oct 2019 09:13:34 +0000 Subject: [PATCH] um-ubd: Entrust re-queue to the upper layers 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 Signed-off-by: Jens Axboe --- arch/um/drivers/ubd_kern.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c index 612535cd9706..6627d7c30f37 100644 --- 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 blk_mq_hw_ctx *hctx, 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; }