I was going through my set of kernel patches that I've cherry picked on LKML for my private kernel, and I noticed this hasn't gotten merged into mainline yet. The original thread was here:
http://lkml.org/lkml/2007/10/27/61 and addressed a panic after a umount reported by Sebastian Siewior. Was this addressed in some other way? - Ted diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 61fdaf0..4042269 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1115,6 +1115,8 @@ static int scsi_init_io(struct scsi_cmnd *cmd) * kmapping pages) */ cmd->use_sg = req->nr_phys_segments; + if (!cmd->use_sg) + return 0; /* * If sg table allocation fails, requeue request later. @@ -1191,7 +1193,7 @@ int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req) if (req->bio) { int ret; - BUG_ON(!req->nr_phys_segments); + BUG_ON(!req->nr_phys_segments && req->bio->bi_size); ret = scsi_init_io(cmd); if (unlikely(ret)) @@ -1236,9 +1238,11 @@ int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req) if (ret != BLKPREP_OK) return ret; /* - * Filesystem requests must transfer data. + * Filesystem requests must transfer data, unless it's an empty + * barrier. */ - BUG_ON(!req->nr_phys_segments); + if (!req->nr_phys_segments && !bio_empty_barrier(req->bio)) + blk_dump_rq_flags(req, "scsi"); cmd = scsi_get_cmd_from_req(sdev, req); if (unlikely(!cmd)) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/