On Wed, 2005-12-21 at 04:24 -0800, David Caldwell wrote: > This patch does 2 things. It reimplements the SG_FLAG_LUN_INHIBIT flag > in the SG_IO ioctl which stops the scsi subsystem from overwriting the > 2nd byte of the CDB with the LUN. It also doesn't guess the CDB length > when sending the SG_IO ioctl to the sg device (the main scsi_ioctl > already did this). > > This is for the Cypress CY7C68310 USB to ATA bridge chip (and most > likely other USB to ATA chips from Cypress), which implements an ATA > passthrough command that is 16 bytes long and starts with the bytes > 0x24 0x24. (Not vendor unique, weird length for opcode 0x24, and > misuse of the LUN area all at the same time--Lovely). I think this approach is too invasive to the stack. When this was discussed in november, there wasn't much enthusiasm for resurrecting the long dead LUN_INHIBIT flag. The two suggested mechanisms are 1) Simply don't mangle the LUN for SCSI_UNKNOWN and then have all the subsystems lying about SCSI_2 compliance instead set their mangled level to SCSI_UNKNOWN (which seems to be more truthful) 2) If 1) doesn't work, then use a blacklist entry which the subsystems would also have access to. James - : 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
