Re: [stable 4.9] PANIC: double fault, error_code: 0x0 - clang boot failed on x86_64

[Nick Desaulniers]

On Wed, Nov 25, 2020 at 10:38 PM Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> Is the mainline 4.9 tree supposed to work with clang?  I didn't think
> that upstream effort started until 4.19 or so.

(For historical records, separate from the initial bug report that
started this thread)

I consider 785f11aa595b ("kbuild: Add better clang cross build
support") to be the starting point of a renewed effort to upstream
clang support. 785f11aa595b landed in v4.12-rc1.  I think most patches
landed between there and 4.15 (would have been my guess).  From there,
support was backported to 4.14, 4.9, and 4.4 for x86_64 and aarch64.
We still have CI coverage of those branches+arches with Clang today.
Pixel 2 shipped with 4.4+clang, Pixel 3 and 3a with 4.9+clang, Pixel 4
and 4a with 4.14+clang.  CrOS has also shipped clang built kernels
since 4.4+.
-- 
Thanks,
~Nick Desaulniers