From: Bart Van Assche <bart.vanassche@xxxxxxx> This patch has been added to the v4.1 stable tree. If you have any objections, please let us know. =============== [ Upstream commit 5fbd545cd3fd311ea1d6e8be4cedddd0ee5684c7 ] Ensure that the members of struct skd_msg_buf have been transferred to the PCIe adapter before the doorbell is triggered. This patch avoids that I/O fails sporadically and that the following error message is reported: (skd0:STM000196603:[0000:00:09.0]): Completion mismatch comp_id=0x0000 skreq=0x0400 new=0x0000 Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Cc: Hannes Reinecke <hare@xxxxxxx> Cc: Johannes Thumshirn <jthumshirn@xxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> --- drivers/block/skd_main.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/block/skd_main.c b/drivers/block/skd_main.c index 99adff0c6f62..f928e698f659 100644 --- a/drivers/block/skd_main.c +++ b/drivers/block/skd_main.c @@ -2214,6 +2214,9 @@ static void skd_send_fitmsg(struct skd_device *skdev, */ qcmd |= FIT_QCMD_MSGSIZE_64; + /* Make sure skd_msg_buf is written before the doorbell is triggered. */ + smp_wmb(); + SKD_WRITEQ(skdev, qcmd, FIT_Q_COMMAND); } @@ -2260,6 +2263,9 @@ static void skd_send_special_fitmsg(struct skd_device *skdev, qcmd = skspcl->mb_dma_address; qcmd |= FIT_QCMD_QID_NORMAL + FIT_QCMD_MSGSIZE_128; + /* Make sure skd_msg_buf is written before the doorbell is triggered. */ + smp_wmb(); + SKD_WRITEQ(skdev, qcmd, FIT_Q_COMMAND); } -- 2.11.0