Re: Buggy commit tracked to: "Re: [PATCH 2/9] iov_iter: move rw_copy_check_uvector() into lib/iov_iter.c"

Al Viro
2020-10-22T20:09:21Z

On Thu, Oct 22, 2020 at 09:06:29PM +0100, Al Viro wrote:
> On Thu, Oct 22, 2020 at 08:24:58PM +0100, Al Viro wrote:
>
> > Depending upon the calling conventions, compiler might do truncation in caller or
> > in a callee, but it must be done _somewhere_.
>
> Unless I'm misreading AAPCS64,
> "Unlike in the 32-bit AAPCS, named integral values must be narrowed by the callee
> rather than the caller"
> in 6.4.2 means that callee must not _not_ expect the upper 32 bits of %x0..%x7 to contain

Sorry, artefact of editing - that's

"in 6.4.2 means that callee must _not_ expect the upper 32 bits of %x0..%x7 to contain"

obviously.