James Bottomley wrote: > On Mon, 2006-12-04 at 15:32 -0800, Darrick J. Wong wrote: >> The Quantum GoVault SATAPI removable disk device returns ATA_ERR in >> response to a REPORT LUNS packet. If this happens to an ATAPI device >> that is attached to a SAS controller (this is the case with sas_ata), >> the device does not load because SCSI won't touch a "SCSI device" >> that won't report its LUNs. Since most ATAPI devices don't support >> multiple LUNs anyway, we might as well fake a response like we do for >> ATA devices. > > Actually, there may be a standards conflict here. SPC says that all > devices reporting compliance with this standard (as the inquiry data for > this device claims) shall support REPORT LUNS. On the other hand, MMC > doesn't list REPORT LUNS in its table of mandatory commands. MMC-5 rev 4 section 7.1: "Some commands that may be implemented by MM drives are not described in this standard, but are found in other SCSI standards. For a complete list of these commands refer to [SPC-3]." Hmm, "may be implemented" yet REPORT LUNS is mandatory in SPC-3 (and SPC-3 is a normative reference for MMC-5). I guess there is wriggle room there. In practice, MMC diverges from SPC a lot more than other SCSI device type command sets (e.g. SBC and SSC). > I'm starting to think that even if they report a SCSI compliance level > of 3 or greater, we still shouldn't send REPORT LUNS to devices that > return MMC type unless we have a white list override. There is also SAT compliance. For the ATA command set (i.e. disks) sat-r09 lists REPORT LUNS and refers to SPC-3. For ATAPI sat-r09 is far less clear. It does recommend, for example, that the ATA Information VPD pages is implemented in the SATL for ATAPI devices. Doug Gilbert - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
