On Thu, 6 Nov 2014, Boaz Harrosh wrote: > On 11/06/2014 05:54 PM, James Bottomley wrote: > > > > We don't have a failure. This is the problem. Determining that a > > problem exists > > > > OK Sorry. I assumed the bridge is smart enough to do nothing, > > ie READ_CAPACITY_10 is passed as is via sata to the device that > actually supports READ_CAPACITY_16, as I understand then the > actual good drive is not suppose to send size-modulue-2G in > response to READ_CAPACITY_10. Should it ? The bridge does not send SCSI commands to the drive; it sends ATA commands. When the bridge receives a READ CAPACITY(10) command from the host computer, if the drive's actual capacity is >= 2^32 blocks then the bridge is supposed to send back a result buffer containing 0xffffffff. Not the actual capacity modulo 2^32. > Then the bridge just sends that back to me, now if I send > READ_CAPACITY_16 the bridge will return NOT-SUPPORTED because > it is unexpected. Yes. > But what are you saying that the bridge was smart enough to > do READ_CAPACITY_16 get a 64bit value from the drive and then > return the lower 32bit to me ? Really ? I would not imagine > in the life of me someone so dumb. And surly it is against > any spec. The bridge does not send READ CAPACITY(16) to the drive. It sends an ATA command -- and it probably sends the same command for READ CAPACITY(10). > Are you sure ? I think you are wrong I think the guy reported > that he can only see 2T out of his 3T drive which means the > bridge returned 0xffffffff, exactly 2T We are sure. Dale reported that the size he got was less than 2 TB, and it was equal to the actual capacity modulo 2^32. You can check for yourself; here's the original email: http://marc.info/?l=linux-scsi&m=140908235510961&w=2 Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
