On 09/05/2009 10:53 AM, FUJITA Tomonori wrote: > On Thu, 03 Sep 2009 07:40:43 +0200 > Florian Haas <florian.haas@xxxxxxxxxx> wrote: > >> Fujita-san, >> >> On 2009-09-02 07:02, FUJITA Tomonori wrote: >>> You mean that MSSC sends TARGET_WARM_RESET (or TARGET_COLD_RESET)? >>> Note that there is no 'bus reset' thing. >> In SCSI2, TARGET_RESET was called BUS_DEVICE_RESET (at least in the >> defines inside the Linux source tree). >> >> And yes, the Windows SCSI stack does a "SCSI bus reset", colloquially >> speaking, whatever that is translated to in iSCSI speak. > > 'SCSI bus reset' is really old and obsolete, I think. FWIW, sg_reset from sg3-utils uses the term "bus reset" both in its man page and in its '--help' output. >>> BTW, IET doesn't correctly handle any reset commands (i.e. it doesn't >>> handle UA). I wrote IET so I know exactly what it does. >> Yes, I know you wrote it, and I know it does not handle the Unit >> Attention stuff, but at least it preempts the SCSI-2 reservations >> on target reset. Does it not? > > If just preempting the reservation on target reset (as IET does) works > for you, the following patch might work (sorry, I've not tested the > path at all because open-iscsi doesn't support > TARGET_WARM|COLD_RESET): Unfortunately the patch does not work for me, using the sg_raw/sg_reset procedure I described earlier in this thread. I can now do a "bus reset" with "sg_reset -b <device>", and it does complete. But attempting a reservation thereafter still results in a reservation conflict. To complicate matters, attempting another RESERVE from the same host, on the same device, now results in a reservation conflict too. Complicating things still, attempting a RELEASE on a previously RESERVEd LU, on the same host now results in a reservation conflict as well. Effectively, after a bus reset, once-acquired reservations are completely broken: they can't be released, and they can't be re-acquired. The same thing is true when attempting to preempt a reservation via a host reset (sg_reset -h <device>). Only a device reset preempts the reservation correctly. Hope this helps. I'll be happy to test an updated version of the patch if I can be of help. Best regards, Florian
Attachment:
signature.asc
Description: OpenPGP digital signature
