Re: [PATCH] x86/fpu: Load xsave pointer *after* initialization

From: Rik van Riel
Date: Thu Apr 16 2015 - 14:15:03 EST


On 04/16/2015 02:05 PM, Borislav Petkov wrote:
> From: Borislav Petkov <bp@xxxxxxx>
>
> So I was playing with gdb today and did this simple thing:
>
> gdb /bin/ls
>
> ...
>
> (gdb) run
>
> Box exploded with the splat at the end because we do cache
> &target->thread.fpu.state->xsave into the local variable xsave but
> that pointer is NULL at that time and it gets initialized later, in
> init_fpu(), see

> Signed-off-by: Borislav Petkov <bp@xxxxxxx>
> Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
> Cc: Rik van Riel <riel@xxxxxxxxxx>
> Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
> Cc: H. Peter Anvin <hpa@xxxxxxxxx>
> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> Cc: Tavis Ormandy <taviso@xxxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

Reviewed-by: Rik van Riel <riel@xxxxxxxxxx>
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