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Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining...
authorIngo Molnar <mingo@kernel.org>
Wed, 19 Dec 2018 10:20:23 +0000 (11:20 +0100)
committerIngo Molnar <mingo@kernel.org>
Wed, 19 Dec 2018 10:58:10 +0000 (11:58 +0100)
commite769742d35841a8198dd6af94e2931083abdee08
tree092cf92b8f35cc4317b75442a90dfce4a2c368d9
parent32043fa065b51e0b1433e48d118821c71b5cd65d
Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"

This reverts commit 5bdcd510c2ac9efaf55c4cbd8d46421d8e2320cd.

The macro based workarounds for GCC's inlining bugs caused regressions: distcc
and other distro build setups broke, and the fixes are not easy nor will they
solve regressions on already existing installations.

So we are reverting this patch and the 8 followup patches.

What makes this revert easier is that GCC9 will likely include the new 'asm inline'
syntax that makes inlining of assembly blocks a lot more robust.

This is a superior method to any macro based hackeries - and might even be
backported to GCC8, which would make all modern distros get the inlining
fixes as well.

Many thanks to Masahiro Yamada and others for helping sort out these problems.

Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: Richard Biener <rguenther@suse.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/entry/calling.h
arch/x86/include/asm/jump_label.h
arch/x86/kernel/macros.S