Re: [patch for 4.0] x86: silence warning in /dev/mem support

[Pavel Machek <pavel@ucw.cz>]

On Thu 2015-04-16 12:09:54, Ingo Molnar wrote:
> 
> * Pavel Machek <pavel@ucw.cz> wrote:
> 
> > The compiler is right, the code is tricky, but it is also correct
> > AFAICT.
> > 
> > Signed-off-by: Pavel Machek <pavel@ucw.cz>
> > 
> > diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
> > index fdf617c..8a8dce8 100644
> > --- a/arch/x86/mm/ioremap.c
> > +++ b/arch/x86/mm/ioremap.c
> > @@ -341,7 +341,7 @@ void *xlate_dev_mem_ptr(phys_addr_t phys)
> >  
> >  	addr = (void __force *)ioremap_cache(start, PAGE_SIZE);
> >  	if (addr)
> > -		addr = (void *)((unsigned long)addr | (phys & ~PAGE_MASK));
> > +		addr = (void *)((unsigned long)addr | (unsigned long) (phys & ~PAGE_MASK));
> 
> What warning did it generate and which compiler version?


  CC      arch/x86/mm/ioremap.o
  arch/x86/mm/ioremap.c: In function ‘xlate_dev_mem_ptr’:
  arch/x86/mm/ioremap.c:363:10: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
     addr = (void *)((unsigned long)addr | (phys & ~PAGE_MASK));
               ^
  LD      arch/x86/mm/built-in.o
		 
pavel@amd:/data/l/linux$ gcc --version
gcc (Debian 4.9.2-10) 4.9.2

(Patch should apply to today's 4.1-rc0, too).

Best regards,
									Pavel
-- 
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