2018-03-23 13:39:40

by Johannes Thumshirn

Subject: [PATCH] scsi: don't look for NULL devices handlers by name

Currently scsi_dh_lookup() doesn't check for NULL as a device
name. This combined with nvme over dm-mapth results in the following
messages emitted by device-mapper:

device-mapper: multipath: Could not failover device 259:67: Handler scsi_dh_(null) error 14.

Let scsi_dh_lookup() fail fast on NULL names.

Signed-off-by: Johannes Thumshirn <[email protected]>
---
drivers/scsi/scsi_dh.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/scsi/scsi_dh.c b/drivers/scsi/scsi_dh.c
index b88b5dbbc444..188f30572aa1 100644
--- a/drivers/scsi/scsi_dh.c
+++ b/drivers/scsi/scsi_dh.c
@@ -112,6 +112,9 @@ static struct scsi_device_handler *scsi_dh_lookup(const char *name)
{
struct scsi_device_handler *dh;

+ if (!name || strlen(name) == 0)
+ return NULL;
+
dh = __scsi_dh_lookup(name);
if (!dh) {
request_module("scsi_dh_%s", name);
--
2.13.6

2018-03-26 10:58:17

by Hannes Reinecke

Subject: Re: [PATCH] scsi: don't look for NULL devices handlers by name

On Fri, 23 Mar 2018 14:37:05 +0100
Johannes Thumshirn <[email protected]> wrote:

> Currently scsi_dh_lookup() doesn't check for NULL as a device
> name. This combined with nvme over dm-mapth results in the following
> messages emitted by device-mapper:
>
> device-mapper: multipath: Could not failover device 259:67: Handler
> scsi_dh_(null) error 14.
>
> Let scsi_dh_lookup() fail fast on NULL names.
>
> Signed-off-by: Johannes Thumshirn <[email protected]>
> ---
> drivers/scsi/scsi_dh.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/scsi/scsi_dh.c b/drivers/scsi/scsi_dh.c
> index b88b5dbbc444..188f30572aa1 100644
> --- a/drivers/scsi/scsi_dh.c
> +++ b/drivers/scsi/scsi_dh.c
> @@ -112,6 +112,9 @@ static struct scsi_device_handler
> *scsi_dh_lookup(const char *name) {
> struct scsi_device_handler *dh;
>
> + if (!name || strlen(name) == 0)
> + return NULL;
> +
> dh = __scsi_dh_lookup(name);
> if (!dh) {
> request_module("scsi_dh_%s", name);

Reviewed-by: Hannes Reinecke <[email protected]>

Cheers,

Hannes

2018-03-26 23:03:09

by Bart Van Assche

Subject: Re: [PATCH] scsi: don't look for NULL devices handlers by name

On Fri, 2018-03-23 at 14:37 +0100, Johannes Thumshirn wrote:
> Currently scsi_dh_lookup() doesn't check for NULL as a device
> name. This combined with nvme over dm-mapth results in the following
> messages emitted by device-mapper:
>
> device-mapper: multipath: Could not failover device 259:67: Handler scsi_dh_(null) error 14.
>
> Let scsi_dh_lookup() fail fast on NULL names.

Reviewed-by: Bart Van Assche <[email protected]>

2018-03-28 22:18:58

by Martin K. Petersen

Subject: Re: [PATCH] scsi: don't look for NULL devices handlers by name

Johannes,

> Currently scsi_dh_lookup() doesn't check for NULL as a device
> name. This combined with nvme over dm-mapth results in the following
> messages emitted by device-mapper:

Applied to 4.16/scsi-fixes. Thank you!

--
Martin K. Petersen Oracle Linux Engineering