Re: Build regressions/improvements in v5.9-rc8

[Richard Weinberger]

On Wed, Oct 7, 2020 at 1:51 PM Paul Bolle <pebolle@xxxxxxxxxx> wrote:
>
> [Added Richard and Anton.]
>
> Andy Shevchenko schreef op ma 05-10-2020 om 15:58 [+0300]:
> > On Mon, Oct 05, 2020 at 11:35:33AM +0200, Geert Uytterhoeven wrote:
> > > On Mon, Oct 5, 2020 at 11:33 AM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> > > > JFYI, when comparing v5.9-rc8[1] to v5.9-rc7[3], the summaries are:
> > > >   - build errors: +3/-6
> >
> > Thanks for the report!
> >
> > >   + /kisskb/src/drivers/gpio/gpiolib-cdev.c: error: implicit
> > > declaration of function 'in_ia32_syscall'
> > > [-Werror=implicit-function-declaration]:  => 430:6
> > >   + /kisskb/src/drivers/gpio/gpiolib-cdev.c: error: unknown type name
> > > 'compat_u64':  => 432:4
> > >
> > > x86_64/um-all{mod,yes}config
> >
> > I guess the quick fix is to disable that code for UML, I don't know how IOCTLs
> > are working in UML in cases when host - guest - guest app either from:
> >       1. x86_64 - x86_64 - i386;
> >       2. x86_64 - i386 - i386.
>
> I ran into this build error too.
>
> Perhaps the UML maintainers have an idea what to do here. The commit that
> triggers this error is 5ad284ab3a01 ("gpiolib: Fix line event handling in
> syscall compatible mode").

UML has no ia32 emulation and therefore no in_ia32_syscall().
Maybe you can check for CONFIG_IA32_EMULATION too?

-- 
Thanks,
//richard