On Wed, Jul 19, 2017 at 03:13:34AM -0500, Jason L Tibbitts III wrote: > [ 46.304530] sg_is_valid_dxfer: dxfer_direction: -2, dxfer_len: 0 Ahh now I see the -2 (SG_DXFER_TO_DEV) is the crucial point here. It is 0 in your case. This would "fix" it but I'm not generally sure it is _the_ solution: diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 1e82d4128a84..b421ec81d775 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -764,7 +764,7 @@ static bool sg_is_valid_dxfer(sg_io_hdr_t *hp) return true; case SG_DXFER_TO_DEV: case SG_DXFER_TO_FROM_DEV: - if (!hp->dxferp || hp->dxfer_len == 0) + if (!hp->dxferp) return false; return true; case SG_DXFER_UNKNOWN: Doug, what are the rules for SG_DXFER_TO_{FROM_}DEV? Apparently we can't be sure len > 0, can we rely on dxferp being present? Thanks, Johannes -- Johannes Thumshirn Storage jthumshirn@xxxxxxx +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg) Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850