Re: [PATCH v2 1/1] x86/Makefile: make -stack-alignment conditional on LLD < 13.0.0

From: Kees Cook
Date: Fri Jun 11 2021 - 14:23:19 EST


On Thu, Jun 10, 2021 at 04:58:24PM -0700, Nick Desaulniers wrote:
> On Thu, Jun 10, 2021 at 4:47 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> >
> > On Thu, Jun 10, 2021 at 03:58:57PM -0700, Nick Desaulniers wrote:
> > > On Thu, Jun 10, 2021 at 3:50 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> > > >
> > > > On Thu, 10 Jun 2021 20:58:06 +0000, Tor Vic wrote:
> > > > > Since LLVM commit 3787ee4, the '-stack-alignment' flag has been dropped
> > > > > [1], leading to the following error message when building a LTO kernel
> > > > > with Clang-13 and LLD-13:
> > > > >
> > > > > ld.lld: error: -plugin-opt=-: ld.lld: Unknown command line argument
> > > > > '-stack-alignment=8'. Try 'ld.lld --help'
> > > > > ld.lld: Did you mean '--stackrealign=8'?
> > > > >
> > > > > [...]
> > > >
> > > > Applied to for-next/clang/features, thanks!
> > > >
> > > > [1/1] x86/Makefile: make -stack-alignment conditional on LLD < 13.0.0
> > > > https://git.kernel.org/kees/c/e6c00f0b33ad
> > >
> > > Can we get this into 5.13?
> >
> > What's the ETA on LLVM 13.0? I was going to put this in -next, marked
> > for stable, but we're about 3 weeks from 5.14 merge window.
>
> Not soon; CI is red over this currently:
> mainline:
> https://github.com/ClangBuiltLinux/continuous-integration2/runs/2796736763?check_suite_focus=true
> https://github.com/ClangBuiltLinux/continuous-integration2/runs/2796736978?check_suite_focus=true
> linux-next:
> https://github.com/ClangBuiltLinux/continuous-integration2/runs/2791754316?check_suite_focus=true
> https://github.com/ClangBuiltLinux/continuous-integration2/runs/2791754426?check_suite_focus=true
> https://github.com/ClangBuiltLinux/continuous-integration2/runs/2792796551?check_suite_focus=true
> etc

Fair enough. Pull request sent to Linus...

--
Kees Cook