Re: [PATCH 14/18] scsi: Make scsi_initialize_rq() zero the entire struct scsi_cmnd

Christoph Hellwig
2017-05-21T06:49:19Z

On Fri, May 19, 2017 at 11:30:12AM -0700, Bart Van Assche wrote:
> This simplifies the memset() call in scsi_initialize_rq() and avoids
> that any stale data is left behind in struct scsi_request.
>
> Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
> Cc: Christoph Hellwig <hch@lst.de>
> Cc: Hannes Reinecke <hare@suse.com>
> ---
> drivers/scsi/scsi_lib.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
> index eeb668935836..791bae192bfb 100644
> --- a/drivers/scsi/scsi_lib.c
> +++ b/drivers/scsi/scsi_lib.c
> @@ -1160,11 +1160,9 @@ static void scsi_initialize_rq(struct request *rq)
> void *buf = cmd->sense_buffer;
> void *prot = cmd->prot_sdb;
>
> - /* zero out the cmd, except for the embedded scsi_request */
> - memset((char *)cmd + sizeof(cmd->req), 0,
> - sizeof(*cmd) - sizeof(cmd->req) + dev->host->hostt->cmd_size);
> + memset(cmd, 0, blk_queue_cmd_size(rq->q));
> scsi_req_init(&cmd->req);
> - cmd->req.sense = cmd->sense_buffer;
> + cmd->req.sense = buf;
> cmd->device = dev;
> cmd->sense_buffer = buf;

maybe move the two sense buffer initializations together?

Otherwise this looks fine:

Reviewed-by: Christoph Hellwig <hch@lst.de>