On Thu, May 10, 2007 at 03:01:44PM +0200, Andi Kleen wrote:
> On Wed, May 09, 2007 at 12:56:16PM -0700, Pete Zaitcev wrote:
> > Hi, Andi:
> > 
> > The attached patch (actually, git show output) makes my Dell 1501 to hang
> > on boot. Sorry, I have no clue why... The culprit is found with git bisect.
> > But yes, it's an AMD MK-36. I use an x86_64 kernel. It is 100% reproducible.
> 
> MK-36? Does it have SVM? 
> 
> Anyways we previously had issues with this being miscompiled, but 
> I thought the latest patch should have been ok. What compiler do you use?
> 
> Can you send me a disassembly listing of arch/x86_64/kernel/time.o?

I debugged this problem a bit and my compiler[1]interprets the =A
constraint as %rax instead of %edx:%eax on x86_64 which causes the
problem. The appended patch provides a workaround for this and fixed the
hang on my machine.

[1] gcc version 4.1.3 20070429 (prerelease) (Debian 4.1.2-5)

Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

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