Re: [RFC][CFT][PATCHSET v1] uaccess unification

From: Al Viro
Date: Tue Apr 04 2017 - 16:53:20 EST


On Tue, Apr 04, 2017 at 01:26:29PM -0700, Max Filippov wrote:
> On Wed, Mar 29, 2017 at 06:57:06AM +0100, Al Viro wrote:
> > I hope that infrastructure part is stable enough to put it into never-rebased
> > state. Some of per-architecture branches might be even done right; however,
> > most of them got no testing whatsoever, so any help with testing (as well
> > as "Al, for fuck sake, dump that garbage of yours, here's the correct patch"
> > from maintainers) would be very welcome. So would the review, of course.
>
> For the xtensa part:
> Tested-by: Max Filippov <jcmvbkbc@xxxxxxxxx>
>
> I believe that the xtensa part needs the following correction:

Applied.

> ---8<---
> >From 4505d69c3514fb12405409a7943e45831d037960 Mon Sep 17 00:00:00 2001
> From: Max Filippov <jcmvbkbc@xxxxxxxxx>
> Date: Tue, 4 Apr 2017 13:20:34 -0700
> Subject: [PATCH] xtensa: fix prefetch in the raw_copy_to_user
>
> 'from' is the input buffer, it should be prefetched with prefetch, not
> prefetchw.
>
> Signed-off-by: Max Filippov <jcmvbkbc@xxxxxxxxx>
> ---
> arch/xtensa/include/asm/uaccess.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/xtensa/include/asm/uaccess.h b/arch/xtensa/include/asm/uaccess.h
> index 8e93ed8..2e7bac0 100644
> --- a/arch/xtensa/include/asm/uaccess.h
> +++ b/arch/xtensa/include/asm/uaccess.h
> @@ -245,7 +245,7 @@ raw_copy_from_user(void *to, const void __user *from, unsigned long n)
> static inline unsigned long
> raw_copy_to_user(void __user *to, const void *from, unsigned long n)
> {
> - prefetchw(from);
> + prefetch(from);
> return __xtensa_copy_user((__force void *)to, from, n);
> }
> #define INLINE_COPY_FROM_USER
> ---8<---
>
> --
> Thanks.
> -- Max