Segher Boessenkool <seg...@kernel.crashing.org> writes:
> On Wed, Jul 29, 2020 at 03:44:56PM -0400, Vladis Dronov wrote:
>> > > Certain warnings are emitted for powerpc code when building with a gcc-10
>> > > toolset:
>> > >
>> > > WARNING: modpost: vmlinux.o(.text.unlikely+0x377c): Section mismatch
>> > > in
>> > > reference from the function remove_pmd_table() to the function
>> > > .meminit.text:split_kernel_mapping()
>> > > The function remove_pmd_table() references
>> > > the function __meminit split_kernel_mapping().
>> > > This is often because remove_pmd_table lacks a __meminit
>> > > annotation or the annotation of split_kernel_mapping is wrong.
>> > >
>> > > Add the appropriate __init and __meminit annotations to make modpost not
>> > > complain. In all the cases there are just a single callsite from another
>> > > __init or __meminit function:
>> > >
>> > > __meminit remove_pagetable() -> remove_pud_table() -> remove_pmd_table()
>> > > __init prom_init() -> setup_secure_guest()
>> > > __init xive_spapr_init() -> xive_spapr_disabled()
>> >
>> > So what changed? These functions were inlined with older compilers, but
>> > not anymore?
>>
>> Yes, exactly. Gcc-10 does not inline them anymore. If this is because of my
>> build system, this can happen to others also.
>>
>> The same thing was fixed by Linus in e99332e7b4cd ("gcc-10: mark more
>> functions
>> __init to avoid section mismatch warnings").
>
> It sounds like this is part of "-finline-functions was retuned" on
> <https://gcc.gnu.org/gcc-10/changes.html>? So everyone should see it
> (no matter what config or build system), and it is a good thing too :-)
I haven't seen it in my GCC 10 builds, so there must be some other
subtlety. Probably it depends on details of the .config.
cheers
