Re: [PATCH] Fix possible FPU information on SVM

["Joerg Roedel" <joerg.roedel-5C7GfCeVMHo@public.gmane.org>]

On Thu, Jun 07, 2007 at 05:51:33PM +0300, Avi Kivity wrote:
> Joerg Roedel wrote:
> >
> >These error pointers could be read from the host userspace which has
> >normally no access to the guest FPU state. So I think they should also
> >be cleared at guest exit.
> >
> >  
> 
> Host userspace has access through the ioctl that gets the fpu state
> (as well as full access to memory and registers).

Ok, agreed. I saw the problem with other applications than the QEMU.
But the other application has to execute FPU instructions to read these
pointers and this would trigger the Linux FPU switching code. This would
also clear these registers.

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