[ TO Mark Rutland ]

Hi,

I was able to build a Linux v4.18-rc6 with tip.git#locking/core [1] on
top of it here on Debian/buster AMD64.

The patch of interest is [2]...

df79ed2c0643 locking/atomics: Simplify cmpxchg() instrumentation

...and some more locking/atomics[/x86] may be interesting.

I had also to apply an asm-goto fix to reduce the number of warnings
when building with clang-7 (version
7.0.0-svn337957-1~exp1+0~20180725200907.1908~1.gbpcccb1b (trunk)).

CONFIG_DRM_AMDGPU=m is BROKEN and a known issue [3].

I had to hack my fakeroot-sysv binary to workaround a fatal build-stop
by commenting the part "nested operation not yet supported" when using
bindeb-pkg make-target.

The kernel does ***not boot*** on bare metal.

More details see [4] and [5] for the clang-side.

- Sedat -

[1] https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/log/?h=locking/core
[2] https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?h=locking/core&id=df79ed2c064363cdc7d2d896923c1885d4e30520
[3] https://lists.freedesktop.org/archives/amd-gfx/2018-July/024634.html
[4] https://github.com/ClangBuiltLinux/linux/issues/3
[5] https://bugs.llvm.org/show_bug.cgi?id=33587