Re: [PATCH] x86: Fix location of '-plugin-opt=' flags

From: Kees Cook
Date: Fri May 21 2021 - 13:59:47 EST


On Tue, 18 May 2021 12:01:06 -0700, Nathan Chancellor wrote:
> Commit b33fff07e3e3 ("x86, build: allow LTO to be selected") added a
> couple of '-plugin-opt=' flags to KBUILD_LDFLAGS because the code model
> and stack alignment are not stored in LLVM bitcode. However, these flags
> were added to KBUILD_LDFLAGS prior to the emulation flag assignment,
> which uses ':=', so they were overwritten and never added to $(LD)
> invocations. The absence of these flags caused misalignment issues in
> the AMDGPU driver when compiling with CONFIG_LTO_CLANG, resulting in
> general protection faults.
>
> [...]

(I've slightly adjusted the title.)

Applied to for-next/clang/features, thanks!

[1/1] x86: lto: Fix location of '-plugin-opt=' flags
https://git.kernel.org/kees/c/5d6c8592ee5f

--
Kees Cook