Re: linux-next: Tree for Jul 6 (arch/riscv/)

[Randy Dunlap]

Hi Palmer,

On 7/6/23 14:46, Palmer Dabbelt wrote:
> On Thu, 06 Jul 2023 14:36:05 PDT (-0700), rdunlap@xxxxxxxxxxxxx wrote:
>>
>>
>> On 7/6/23 14:32, Palmer Dabbelt wrote:
>>> On Thu, 06 Jul 2023 14:27:53 PDT (-0700), rdunlap@xxxxxxxxxxxxx wrote:
>>>>
>>>>
>>>> On 7/5/23 18:57, Stephen Rothwell wrote:
>>>>> Hi all,
>>>>>
>>>>> Please do *not* add any v6.6 related stuff to your linux-next included
>>>>> branches until after v6.5-rc1 has been released.
>>>>>
>>>>> Changes since 20230705:
>>>>>
>>>>
>>>> on riscv64:
>>>>
>>>> WARNING: modpost: vmlinux: section mismatch in reference: $xrv64i2p1_m2p0_a2p1_zicsr2p0_zifencei2p0_zihintpause2p0_zmmul1p0+0x14 (section: .text.unlikely.set_bit.constprop.0) -> numa_nodes_parsed (section: .init.data)
>>>>
>>>>
>>>> Full randconfig file is attached.
>>>
>>> Thanks, I'm giving it a look.  Do you happen to also have your toolchain version easily availiable?  The mapping symbols are new and we've seen some odd stuff happen, something is likely broken somewhere...
>>
>> I'm using gcc-13.1.0 from  https://mirrors.edge.kernel.org/pub/tools/crosstool/
> 
> Cool, those are pretty easy to run.  I've yet to actually reproduce the
> failures, but I'd guess we just want to ignore the mapping symbols with
> something like
> 
> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
> index b29b29707f10..2f801469301d 100644
> --- a/scripts/mod/modpost.c
> +++ b/scripts/mod/modpost.c
> @@ -614,6 +614,18 @@ static int ignore_undef_symbol(struct elf_info *info, const char *symname)
>         /* Expoline thunks are linked on all kernel modules during final link of .ko */
>         if (strstarts(symname, "__s390_indirect_jump_r"))
>             return 1;
> +
> +    /*
> +     * RISC-V defines various special symbols that start with "$".  The
> +     * mapping symbols, which exist to differentiate between incompatible
> +     * instruction encodings when disassembling, show up all over the place
> +     * and are generally not meant to be treated like other symbols.  So
> +     * just ignore any of the special symbols.
> +     */
> +    if (info->hdr->e_machine == EM_RISCV)
> +        if (symname[0] == '$')
> +            return 1;
> +
>     /* Do not ignore this symbol */
>     return 0;
> }
> 
> I haven't even built that, though...

That builds without any errors or warnings, but it doesn't fix the section mismatch
warning.

> These also trip up backtraces, so we probably need something over there as
> well.

-- 
~Randy