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From:   Alexander Potapenko <glider@google.com>
Date:   Mon, 19 Jun 2023 14:03:59 +0200
Message-ID: <CAG_fn=Un4XhebL8YRnPDjETEYGQCBnwh6vvePPxCLmLeJRTmRg@mail.gmail.com>
Subject: Re: [GIT PULL] x86/mm for 6.4
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     dave.hansen@linux.intel.com, kirill.shutemov@linux.intel.com,
        linux-kernel@vger.kernel.org, peterz@infradead.org, x86@kernel.org
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On Fri, Jun 16, 2023 at 6:22=E2=80=AFPM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> On Fri, 16 Jun 2023 at 01:47, Alexander Potapenko <glider@google.com> wro=
te:
> >
> > Shouldn't ex_handler_copy() be fixed in the same way?
>
> I don't think ex_handler_copy() is actually reachable any more.
>
> The only thing ex_handler_copy() did was to set %ax to the fault type.
>
> It was used by the strange copy_user_generic_unrolled() that had
> special machine check case for "don't do the tail if we get
> X86_TRAP_MC".

Oh, I see, thanks!
I am using a downstream kernel (way before 034ff37d3407) that still
has _ASM_EXTABLE_CPY.
Looks like I just need to adjust ex_handler_copy() in my code.