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

[Christoph Hellwig]

On Wed, Oct 07, 2020 at 04:02:41PM +0300, Andy Shevchenko wrote:
> On Wed, Oct 07, 2020 at 02:45:30PM +0200, Paul Bolle wrote:
> > Richard Weinberger schreef op wo 07-10-2020 om 14:08 [+0200]:
> > > UML has no ia32 emulation and therefore no in_ia32_syscall().
> > > Maybe you can check for CONFIG_IA32_EMULATION too?
> > 
> > The pending fix is:
> >     #if defined(CONFIG_X86_64) && !defined(CONFIG_UML)
> > 
> > Since this check guards in_ia32_syscall() just checking CONFIG_IA32_EMULATION
> > should do too.
> > 
> > (Way outside my limited expertise, but anyway: is does look odd to see a call
> > to in_ia32_syscall() in drivers/. All other calls are in arch/x86/. Isn't this
> > a bit too x86 specific for an arch independent driver?)
> 
> According to Arnd who suggested that fix the problem is basically appears on
> x86. He also mentioned the new approach that Christoph Hellwig is working on.
> But we decided to go the ifdeffery for better backporting.

linux-next has compat_need_64bit_alignment_fixup(), which is the
proper thing to use.  But for now you'll need the ifdef mess.