Re: [akpm-mm:mm-new 320/331] arch/s390/kvm/gaccess.c:321:2: error: expected identifier

[Claudio Imbrenda <imbrenda@linux.ibm.com>]

On Wed, 14 May 2025 14:48:44 +0100
Lorenzo Stoakes <lorenzo.stoakes@oracle.com> wrote:

> +cc s390 people, kvm s390 people + lists. sorry for noise but get_maintainers.pl
> says there's a lot of you :)
> 
> On Wed, May 14, 2025 at 03:28:47PM +0200, Ignacio Moreno Gonzalez wrote:
> > Hi,
> >
> > Due to the line:
> >
> > include/linux/huge_mm.h:509 '#include <uapi/asm/mman.h>'  
> 
> BTW, I didn't notice at the time, but shouldn't this be linux/mman.h? You
> shouldn't be importing this header this way generally (only other users are arch
> code).
> 
> But at any rate, you will ultimately import the PROT_NONE declaration.
> 
> >
> > there is a name collision in arch/s390/kvm/gaccess.c, where 'PROT_NONE' is also defined as value for 'enum prot_type'.  
> 
> That is crazy. Been there since 2022 also...!
> 
> >
> > A possible fix for this would be to rename PROT_NONE in the enum to PROT_TYPE_NONE.  

please write a patch to rename PROT_NONE in our enum to
PROT_TYPE_DUMMY, I can review it quickly.

if Paolo has no objections, I'm fine with having the patch go through
the mm tree

> 
> Yeah this is the correct fix, IMO, but you will need to get that sorted with the
> arch maintainers.
> 
> I think this suggests we should back out this change for now and try again next
> cycle given we haven't much time left.
> 
> Have cc'd s390/kvm for s390 maintainers for their input however!
> 
> >
> > The patch causing this problem was created by me based on a suggestion in the review process of another patch that I submitted first:
> >
> > https://lore.kernel.org/linux-mm/ee95ddf9-0d00-4523-ad2a-c2410fd0e1a3@lucifer.local/
> >
> > In case '#include <uapi/asm/mman.h>' causes unexpected trouble, we can also take the patch back... What do you think?  
> 
> I guess we need to back this out for the time being, since we're so near the end of the cycle.
> 
> >
> > Thanks and regards
> > Ignacio
> >
> > On 5/14/2025 3:05 AM, kernel test robot wrote:  
> > >>> arch/s390/kvm/gaccess.c:344:8: error: duplicate case value: '0' and 'PROT_TYPE_LA' both equal '0'  
> >
> >  
> 
> For convenience, let me include the top of the original report. The full thing
> is at https://lore.kernel.org/all/202505140943.IgHDa9s7-lkp@intel.com/
> 
> The original patch for this is at
> https://lore.kernel.org/all/20250508-madvise-nohugepage-noop-without-thp-v1-1-e7ceffb197f3@kuka.com/
> 
> Original report:
> 
> 
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-new
> head:   24e96425873f27730d30dcfc639a3995e312e6f2
> commit: cd07d277e6acce78e103478ea19a452bcf31013e [320/331] mm: madvise: make MADV_NOHUGEPAGE a no-op if !THP
> config: s390-randconfig-r062-20250514
> +(https://download.01.org/0day-ci/archive/20250514/202505140943.IgHDa9s7-lkp@intel.com/config)
> compiler: clang version 21.0.0git (https://github.com/llvm/llvm-project f819f46284f2a79790038e1f6649172789734ae8)
> reproduce (this is a W=1 build):
> +(https://download.01.org/0day-ci/archive/20250514/202505140943.IgHDa9s7-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202505140943.IgHDa9s7-lkp@intel.com/
> 
> All errors (new ones prefixed by >>):
> 
> >> arch/s390/kvm/gaccess.c:321:2: error: expected identifier  
>      321 |         PROT_NONE,
>          |         ^
>    include/uapi/asm-generic/mman-common.h:16:19: note: expanded from macro 'PROT_NONE'
>       16 | #define PROT_NONE       0x0             /* page can not be accessed */
>          |                         ^
> >> arch/s390/kvm/gaccess.c:344:8: error: duplicate case value: '0' and 'PROT_TYPE_LA' both equal '0'  
>      344 |                 case PROT_TYPE_LA:
>          |                      ^
>    arch/s390/kvm/gaccess.c:337:8: note: previous case defined here
>      337 |                 case PROT_NONE:
>          |                      ^
>    include/uapi/asm-generic/mman-common.h:16:19: note: expanded from macro 'PROT_NONE'
>       16 | #define PROT_NONE       0x0             /* page can not be accessed */
>          |                         ^