Re: [PATCH v5] riscv: Handle zicsr/zifencei issue between gcc and binutils

[Mingzheng Xing]

On 8/25/23 01:33, Conor Dooley wrote:
> On Fri, Aug 25, 2023 at 01:30:36AM +0800, Mingzheng Xing wrote:
> > On 8/24/23 19:32, Mingzheng Xing wrote:
> > > On 8/23/23 21:31, Conor Dooley wrote:
> > > > On Wed, Aug 23, 2023 at 12:51:13PM +0100, Conor Dooley wrote:
> > > > > On Thu, Aug 17, 2023 at 03:20:24PM +0000,
> > > > > patchwork-bot+linux-riscv@xxxxxxxxxx wrote:
> > > > > > Hello:
> > > > > >
> > > > > > This patch was applied to riscv/linux.git (fixes)
> > > > > > by Palmer Dabbelt <palmer@xxxxxxxxxxxx>:
> > > > > >
> > > > > > On Thu, 10 Aug 2023 00:56:48 +0800 you wrote:
> > > > > > > Binutils-2.38 and GCC-12.1.0 bumped[0][1] the default
> > > > > > > ISA spec to the newer
> > > > > > > 20191213 version which moves some instructions from the
> > > > > > > I extension to the
> > > > > > > Zicsr and Zifencei extensions. So if one of the binutils
> > > > > > > and GCC exceeds
> > > > > > > that version, we should explicitly specifying Zicsr and
> > > > > > > Zifencei via -march
> > > > > > > to cope with the new changes. but this only occurs when
> > > > > > > binutils >= 2.36
> > > > > > > and GCC >= 11.1.0. It's a different story when binutils < 2.36.
> > > > > > >
> > > > > > > [...]
> > > > > > Here is the summary with links:
> > > > > >     - [v5] riscv: Handle zicsr/zifencei issue between gcc and binutils
> > > > > >       https://git.kernel.org/riscv/c/ca09f772ccca
> > > > > *sigh* so this breaks the build for gcc-11 & binutils 2.37 w/
> > > > >      Assembler messages:
> > > > >      Error: cannot find default versions of the ISA extension `zicsr'
> > > > >      Error: cannot find default versions of the ISA extension `zifencei'
> > > > >
> > > > > I'll have a poke later.
> > > > So uh, are we sure that this should not be:
> > > > -       depends on (CC_IS_CLANG && CLANG_VERSION < 170000) ||
> > > > (CC_IS_GCC && GCC_VERSION < 110100)
> > > > +       depends on (CC_IS_CLANG && CLANG_VERSION < 170000) ||
> > > > (CC_IS_GCC && GCC_VERSION <= 110100)
> > > >
> > > > My gcc-11.1 + binutils 2.37 toolchain built from riscv-gnu-toolchain
> > > > doesn't have the default versions & the above diff fixes the build.
> > > I reproduced the error, the combination of gcc-11.1 and
> > > binutils 2.37 does cause errors. What a surprise, since binutils
> > > 2.36 and 2.38 are fine.
> > >
> > > I used git bisect to locate this commit[1] for binutils.
> > > I'll test this diff in more detail later. Thanks!
> > >
> > > [1] https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=f0bae2552db1dd4f1995608fbf6648fcee4e9e0c
> > Hi, Conor.
> > The above error does originate from link[1] mentioned above, which was
> > resolved in gcc-12.1.0[2], and gcc-11.3.0 made the backport[3].
> > So gcc-11.2.0 combined with binutils 2.37 produces the same error.
> > I think we should do the following diff to fix it:
> > -       depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC &&
> > GCC_VERSION < 110100)
> > +       depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC &&
> > GCC_VERSION < 110300)
> That sounds good to me. Can you make that a real patch please?

Okey.
Just a question, I see that the previous patch has been merged
into 6.5-rc7, and now a new fix patch should be sent out based
on that, right?


Best Regards,
Mingzheng.

> Thanks for working on it :)