kernel panic trying to utilize a da(4)/umass(4) device with
Brian F. Feldman
green at FreeBSD.org
Fri Nov 21 09:35:52 PST 2003
Doug White <dwhite at gumbysoft.com> wrote:
> The OHCI driver is largely synced with NetBSD so you might see if they
> have the same bug.
I'll look around for a bootable NetBSD CD.
> This might be the underlying wierdness we were seeing in gtetlow's
> microdrive with transfers over 8k. The one-page-crossing ohci limitation
> is really annoying.
Is there a way to add a quirk for max 8k transfers or anything? Even though
that would be patently lame, I'd like to get some sort of workaround here.
I don't even know what is supposed to be the problem here -- the fact that
it's an ohci controller, an ohci+ehci controller, or that it's some specific
> On Thu, 20 Nov 2003, Brian F. Feldman wrote:
> > Thanks for the patches to try! They unfortunately didn't fix the crash I
> > have, but I found out why it's occurring.
> > See ohci.c:1389:
> > if (std->td.td_cbp != 0)
> > len -= le32toh(std->td.td_be) -
> > le32toh(std->td.td_cbp) + 1;
> > In one of my transfers (look in my log for the 2560 byte one) that statement
> > actually adds 8192 to len, which is utterly bogus because you can see it
> > only allocates 2560 -- hence when it tries to finish the transfer it
> > memcpy()'s way too much memory and my kernel segfaults. If I #if 0 this out,
> > I'm left only with "umass0: BBB reset failed, STALLED" messages... which is
> > a lot better than before! I don't know under what situations that bit of
> > code makes sense, but it definitely needs more reviewing!
> Stalls usually come from the device receiving bad data. Rather than
> return errors, usb generally just hangs the endpoint.
Hmm :-/ I wonder if anyone could interpret the debugging info enough to
have an idea what it's disliking for certain.
Brian Fundakowski Feldman \'[ FreeBSD ]''''''''''\
<> green at FreeBSD.org \ The Power to Serve! \
Opinions expressed are my own. \,,,,,,,,,,,,,,,,,,,,,,\
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