Subject: Re: linux-next: manual merge of the s390 tree with the mm-stable tree

From: Stephen Rothwell <[email-masked]>
Date: Wed, 20 Nov 2024 12:20:04 +1100

Hi all,

On Thu, 14 Nov 2024 10:16:39 +1100 Stephen Rothwell <[email-masked]> wrote:
>
> Today's linux-next merge of the s390 tree got a conflict in:
> 
>   arch/s390/mm/pageattr.c
> 
> between commit:
> 
>   0c6378a71574 ("arch: introduce set_direct_map_valid_noflush()")
> 
> from the mm-stable tree and commit:
> 
>   2835f8bf5530 ("s390/pageattr: Implement missing kernel_page_present()")
> 
> from the s390 tree.
> 
> I fixed it up (see below) and can carry the fix as necessary. This
> is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging.  You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.
> 
> 
> diff --cc arch/s390/mm/pageattr.c
> index 4c7ee74aa130,4a0f422cfeb6..000000000000
> --- a/arch/s390/mm/pageattr.c
> +++ b/arch/s390/mm/pageattr.c
> @@@ -406,17 -407,21 +407,33 @@@ int set_direct_map_default_noflush(stru
>   	return __set_memory((unsigned long)page_to_virt(page), 1, SET_MEMORY_DEF);
>   }
>   
>  +int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid)
>  +{
>  +	unsigned long flags;
>  +
>  +	if (valid)
>  +		flags = SET_MEMORY_DEF;
>  +	else
>  +		flags = SET_MEMORY_INV;
>  +
>  +	return __set_memory((unsigned long)page_to_virt(page), nr, flags);
>  +}
> ++
> + bool kernel_page_present(struct page *page)
> + {
> + 	unsigned long addr;
> + 	unsigned int cc;
> + 
> + 	addr = (unsigned long)page_address(page);
> + 	asm volatile(
> + 		"	lra	%[addr],0(%[addr])\n"
> + 		CC_IPM(cc)
> + 		: CC_OUT(cc, cc), [addr] "+a" (addr)
> + 		:
> + 		: CC_CLOBBER);
> + 	return CC_TRANSFORM(cc) == 0;
> + }
> + 
>   #if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KFENCE)
>   
>   static void ipte_range(pte_t *pte, unsigned long address, int nr)

This is now a conflict between the mm-stable tree and Linus' tree.

-- 
Cheers,
Stephen Rothwell