Re: [Qemu-devel] qemu-system-ppc problem with PVR access from user space

[J. Mayer]

On Fri, 2007-11-02 at 08:04 -0500, Jason Wessel wrote:
> The typical kernel + user space I boot on the prep machine no longer
> boots due to an issue accessing the PVR special purpose register.  When
> the PVR is accessed from user space, it should generate an exception
> with the PC set to the instruction that it occurred at when it saves to
> the stack.  In the latest CVS, it is off by 4 bytes.  With out the fix
> /sbin/init gets killed because the kernel's trap handler which does the
> userspace emulation of the instruction does not clean up the trap.
> 
> I am using the attached patch to work around the problem, but I wonder
> if there is a more generic problem that was introduced as a regression
> with all ppc merges in the last month or so, given this used to work
> fine through the generic handler.
> 
> Any insight into this would certainly be useful.

Seems like I made a mistake for program exception generation while
fixing floating-point ones, I'm sorry. Your patch is incorrect but the
one attached should fix the problem. Could you please check it in your
case ?

-- 
J. Mayer <address@hidden>
Never organized

ppc_excp.diff
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