CVS commit: src/sys/dev/pci

["Brian Buhrow" <buhrow%netbsd.org@localhost>]

Module Name:    src
Committed By:   buhrow
Date:           Wed Oct 25 00:21:49 UTC 2023

Modified Files:
        src/sys/dev/pci: mpii.c

Log Message:
Fixes for PR kern/57133:

I can now explain why this assert is firing and have a fix for it.  It is a
 regression introduced in R1.22 of mpii.c.

        If a request comes in and the IOC returns a MPII_SCSIIO_STATUS_CHECK_COND condition, after
 a successful transfer, or one that is a recovered error,
 mpii(4) correctly sets the xs->error to XS_SENSE, but incorrectly sets xs->resid to 0 before
 returning the xfer to the upper scsi layers.  Once the upper layers get it, they notice the
 XS_SENSE check condition and because it's a retryable error, they increment xs_requeuecnt, set
 ERESTART and send the xfer request down to the mpii(4) layer again for a retry.  What they do
 not do is reset xs->resid equal to xs->datalen.  When the xfer comes down to mpii(4) again, the
 assert happens.  The fix is for the mpii(4) driver to leave xs->resid alone when it encounters
 a MPII_SCSIIO_STATUS_CHECK_COND condition.

This bug affects NetBSD-10, netbsd-9 and netbsd-8.


To generate a diff of this commit:
cvs rdiff -u -r1.29 -r1.30 src/sys/dev/pci/mpii.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.