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

David Laight
2020-10-23T14:39:30Z

From: David Hildenbrand
> Sent: 23 October 2020 15:33
...
> I just checked against upstream code generated by clang 10 and it
> properly discards the upper 32bit via a mov w23 w2.
>
> So at least clang 10 indeed properly assumes we could have garbage and
> masks it off.
>
> Maybe the issue is somewhere else, unrelated to nr_pages ... or clang 11
> behaves differently.

We'll need the disassembly from a failing kernel image.
It isn't that big to hand annotate.

David

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