Re: [PATCH 00/15] Add support for clang LTO

From: AKASHI Takahiro
Date: Thu Nov 09 2017 - 05:51:25 EST


On Sat, Nov 04, 2017 at 02:13:04AM +0000, Mark Rutland wrote:
> On Fri, Nov 03, 2017 at 12:56:47PM -0700, Sami Tolvanen wrote:
> > On Fri, Nov 03, 2017 at 07:26:35PM +0000, Mark Rutland wrote:
> > > I guess that in Google you haven't tested on a platform with EL2
> > > available?
> >
> > Correct. I'll look into this and include a fix in v2. Does this work on a
> > clang build without LTO?
>
> I saw this on v4.14-rc7, with patch 7 (-mno-implicit-float), but no other
> patches from this series (i.e. no LTO).


Add -fno-jump-tables to ccflags-y of arch/arm64/kvm/hyp/Makefile.
Without this option, clang generates a branch instruction (br x11)
to an absolute (EL1) virtual address.

-Takahiro AKASHI

> Thanks,
> Mark.