Re: [PATCH 5.15 0/5] Support static calls with LLVM-built kernels

[Sasha Levin <sashal@xxxxxxxxxx>]

On Sat, Mar 16, 2024 at 07:02:19AM -0300, Thadeu Lima de Souza Cascardo wrote:
> On Sat, Mar 16, 2024 at 05:41:16AM -0400, Sasha Levin wrote:
> > On Wed, Mar 13, 2024 at 07:42:50AM -0300, Thadeu Lima de Souza Cascardo wrote:
> > > Peter Zijlstra (4):
> > >  arch: Introduce CONFIG_FUNCTION_ALIGNMENT
> > >  x86/alternatives: Introduce int3_emulate_jcc()
> > >  x86/alternatives: Teach text_poke_bp() to patch Jcc.d32 instructions
> > >  x86/static_call: Add support for Jcc tail-calls
> > >
> > > Thomas Gleixner (1):
> > >  x86/asm: Differentiate between code and function alignment
> >
> > Is this not an issue on 6.1? I don't see d49a0626216b ("arch: Introduce
> > CONFIG_FUNCTION_ALIGNMENT") in that tree.
> >
> > --
> > Thanks,
> > Sasha
>
> The fix is really the last patch, 923510c88d2b ("x86/static_call: Add support
> for Jcc tail-calls"). I see that 6.1 got 3,4,5:
>
> 9d80f3e60043 x86/static_call: Add support for Jcc tail-calls
> c51a456b4179 x86/alternatives: Teach text_poke_bp() to patch Jcc.d32 instructions
> 75c066485bcb x86/alternatives: Introduce int3_emulate_jcc()
>
> I can resubmit the series without the first two patches if that is preferred.

I'm just curious why we needed the first two patches on 5.15 but not on 6.1.

--
Thanks,
Sasha