Hi Marek, On Wed, Jul 01, 2020 at 03:01:03PM +0200, Marek Szyprowski wrote: > Hi > > On 29.06.2020 11:47, Ming Lei wrote: > > It is natural to release driver tag when this request is completed by > > LLD or device since its purpose is for LLD use. > > > > One big benefit is that the released tag can be re-used quicker since > > bio_endio() may take too long. > > > > Meantime we don't need to release driver tag for flush request. > > > > Cc: Christoph Hellwig <hch@xxxxxx> > > Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> > > This patch landed recently in linux-next as commit 36a3df5a4574. Sadly > it causes a regression on one of my test systems (ARM 32bit, Samsung > Exynos5422 SoC based Odroid XU3 board with eMMC). The system boots fine > and then after a few seconds every executed command hangs. No > panic/ops/any other message. I will try to provide more information asap > I find something to share. Simple reverting it in linux-next is not > possible due to dependencies. What is the exact eMMC's driver code(include the host driver)? The usual way for handling completion is that host driver notifies block layer via blk_mq_complete_request() after the LLD specific handling for this request is done. However, there might be driver which may use rq->tag in its rq completion handler. I will see if the special case can be dealt with once you share the driver info. Thanks, Ming
