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> --- 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 edab9c04e8ad..153f20ce318b 100644 --- a/drivers/block/skd_main.c +++ b/drivers/block/skd_main.c @@ -2160,6 +2160,9 @@ 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); } @@ -2202,6 +2205,9 @@ 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); } -- 2.14.0