Bugzilla – Bug 623203
2TB limit + other limits in xen vscsi drivers (patch included)
Last modified: 2010-09-28 15:29:03 UTC
User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.6) Gecko/20100629 Mandriva Linux/1.9.2.6-0.1mdv2010.0 (2010.0) Firefox/3.6.6 The current implementation of the vscsi driver has several serious limitations both on frontend and backend side that can be easily fixed. These lead to the limitation of the maximum partition size to 2TB (due to missing MAX_COMMAND_SIZE and masked out READ_16, WRITE_16,... commands), non-fuctional features on autoloader or tape drives (several scsi commands masked-out), and some issues with multipath (also scsi commands masked). It is completely unclear to me, why so many scsi commands were masked out in emulate.c of the backend driver - the fix was really easy and seems to work nicely. The question is, whether not to remove the remaining command masking in emulate.c at all. I'm attaching a patch for both scsiback and scsifront subdirs. Could somebody review the changes please and take care to add these to the next update ? Reproducible: Always Steps to Reproduce: 1.try to mount >2TB scsi partition over vscsi interface 2.try to use autoloader using vscsi 3.try to use ALUA in multipath using vscsi
Created attachment 376585 [details] recursive patch for both scsiback and scsifront
This really should be sent to xen-devel (with a proper patch description and sign-off), so that the original contributor of the vscsi code could review it. While the changes look reasonable to me (minus some benign changes that should be removed), not knowing this code well I would not want to take this patch without upstream having approved it, at which point we would simply get it from there (though unlikely for 11.2 with 11.3 now being available).
Well, I was hoping, somebody who is anyway involved on the xen-devel mailing list would submit it, just wanted to prevent being subscribed on another mailing list.
The requested information has not been provided for more than 4 weeks. The bug gets therefore closed as NORESPONSE. Please reopen the bug if you can supply the requested information.