On Fri, Feb 20, 2009 at 10:03:15AM -0600, James Bottomley wrote: > > The port isn't coming out of standby state. We send it a TEST_UNIT_READY, > > it replies with a 0x04/0x0b. At that point, we currently decide to send > > it a START_STOP and wait 100 seconds. This is clearly a crappy decision > > on our part, we should just bail. > > So we should be bailing on manual intervention, TP standby and TP > unavailable? It looks like TP assymetric access transition is waitable. I think that's correct (and I think my version of this patch makes that clearer). SPC 4r14 isn't clear on 'Asymmetric Access Transition' -- I can't tell whether that state is entered on transition *to* active, or *from* active, or both. > It also looks like offline and notify (enable spinup) required are also > not worth waiting for ... although the latter is a SAS power management > state which it's not clear to me how to handle properly. Offline is only applicable to M and V (Media Changer and Automation) devices, neither of which should be attached to by sd. I don't know what 'Enable Spinup' is for -- maybe Doug knows? Sending a START_STOP to the device might be exactly what they intend for us to do. Under a 'First, Do No Harm' theory, perhaps we should leave well enough alone and just add Standby and Unavailable? -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step." -- 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
