On 02/20/2017 08:52 AM, Christoph Hellwig wrote:
> Without this drivers that don't clear the state themselves can see off
> effects. For example Hyper-V VMs using the storvsc driver will often
> hang during boot due to uncleared Test Unit Ready failures.
>
> Fixes: e9c787e6 ("scsi: allocate scsi_cmnd structures as part of struct request")
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> Reported-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
> Tested-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
> ---
> drivers/scsi/scsi_lib.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
> index 90f65c8f487a..daced9db8af8 100644
> --- a/drivers/scsi/scsi_lib.c
> +++ b/drivers/scsi/scsi_lib.c
> @@ -1167,6 +1167,7 @@ void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
> /* zero out the cmd, except for the embedded scsi_request */
> memset((char *)cmd + sizeof(cmd->req), 0,
> sizeof(*cmd) - sizeof(cmd->req));
> + memset((char *)(cmd + 1), 0, dev->host->hostt->cmd_size);
Hello Christoph,
Since this code is in the hot path: please combine the two memset()
calls into a single memset() call.
Thanks,
Bart.
