Re: [RFC PATCH] powerpc/spufs: fix copy_to_user while atomic

[Arnd Bergmann]

On Tue, Apr 28, 2020 at 2:05 PM Jeremy Kerr <jk@xxxxxxxxxx> wrote:
>
> Currently, we may perform a copy_to_user (through
> simple_read_from_buffer()) while holding a context's register_lock,
> while accessing the context save area.
>
> This change uses a temporary buffers for the context save area data,
> which we then pass to simple_read_from_buffer.
>
> Signed-off-by: Jeremy Kerr <jk@xxxxxxxxxx>
> ---

Thanks for fixing this!

I wonder how far it should be backported, given that this has been broken for
14 years now.

Fixes: bf1ab978be23 ("[POWERPC] coredump: Add SPU elf notes to coredump.")
Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx>