On Mon, 2014-11-10 at 16:56 +0100, Christoph Hellwig wrote: > - for those drivers looking at the command tagged information we'd need > to quiesce the LUN. No driver but the 53c700 driver does that, and the > 53c700 does it at a target-level, which despite a comment claiming it's > needed doesn't seem to make sense given the code. I can answer that from ancient memory. The mid-layer tag tracking wasn't sufficient to track the negotiated state of the tags. the 53c700 was constructed before the slave alloc/configure routines came along, so it used a per target tracker for the tag negotiation (i.e. it was all on or all off per target). The reason for the quiesce is so as not to have to try to work out if any LUN has any tagged commands outstanding when changing to untagged. James -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html