Re: Hang when mounting XFS root in 2.6.0 tests on x86-64

[Steve Lord <lord@sgi.com>]

On Thu, 2003-08-21 at 16:00, Andi Kleen wrote:
> Chris Meadors <clubneon@hereintown.net> writes:
> 
> Better report it to linux-xfs@oss.sgi.com (cc'ed) too.
> 
> > I'm trying to get a 2.6.0-test kernel to boot on my Opteron system.  It
> > has SuSE's 2.4.19-SMP kernel on it now, and it boots with that, mounts
> > the XFS root just fine.  But I build a vanilla 2.6.0-test3 with no
> > module support, everything included that I would need.  The last line
> > that it prints during boot is the NET4.0
> >
> > Repeated presses of Alt+SysRq+P seems to show RIP looping in xfs_xlatesb
> > and xfs_lowbit64.

Seems to suggest a platform specific problem with this code, Andi,
didn't you write the function behind xfs_lowbit64?

> >
> > I've tried -test3-bk9 and also went back to -test2 and -test1.
> >
> > Earlier when playing with this machine I built 2.6.0-test3 with a 32 bit
> > only version of gcc, but still optimized for the Opteron.  This one had
> > no problem booting and mounting the XFS root.
> >
> > This is easy to reproduce, so let me know if more information is needed.
> 
> I test XFS (but not as root) occasionally on x86-64 and seen no problems 
> so far. I haven't tested it with test2+ yet though.

This code chunk will be the same no matter which filesystem you are
mounting, if the hang happened on an xfs root, I would expect to see
it on any xfs filesystem with that kernel.

> 
> What compiler are you using?
> 

Some disassembly output and help from someone who can read it might
be in order here.

Steve