Re: [PATCH 1/9] mm/maccess: fix unaligned copy_{from,to}_kernel_nofault

From: Linus Walleij
Date: Sun Sep 27 2020 - 05:25:41 EST


On Mon, Sep 7, 2020 at 5:37 PM Arnd Bergmann <arnd@xxxxxxxx> wrote:

> On machines such as ARMv5 that trap unaligned accesses, these
> two functions can be slow when each access needs to be emulated,
> or they might not work at all.
>
> Change them so that each loop is only used when both the src
> and dst pointers are naturally aligned.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

That's a clever optimization idea, nice!
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

Yours,
Linus Walleij