Subject: Re: linux-next: build failure after merge of the akpm tree

From: Stephen Rothwell <[email-masked]>
Date: Thu, 4 Jun 2020 18:24:36 +1000

Hi all,

On Thu, 4 Jun 2020 16:44:42 +1000 Stephen Rothwell <[email-masked]> wrote:
>
> Hi all,
> 
> After merging the akpm tree, today's linux-next build (powerpc
> allyesconfig) failed like this:
> 
> arch/powerpc/mm/ptdump/ptdump.c: In function 'walk_pagetables':
> arch/powerpc/mm/ptdump/ptdump.c:337:25: error: implicit declaration of function 'pgd_is_leaf'; did you mean 'p4d_is_leaf'? [-Werror=implicit-function-declaration]
>   337 |   if (pgd_none(*pgd) || pgd_is_leaf(*pgd))
>       |                         ^~~~~~~~~~~
>       |                         p4d_is_leaf
> 
> Caused by commit
> 
>    "powerpc: add support for folded p4d page tables"
> 
> I applied the following fix up patch.
> 
> From: Stephen Rothwell <[email-masked]>
> Date: Thu, 4 Jun 2020 16:33:01 +1000
> Subject: [PATCH] fixup for powerpc ptdump.c
> 
> Signed-off-by: Stephen Rothwell <[email-masked]>
> ---
>  arch/powerpc/mm/ptdump/ptdump.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/powerpc/mm/ptdump/ptdump.c b/arch/powerpc/mm/ptdump/ptdump.c
> index 9b1c89b05622..de6e05ef871c 100644
> --- a/arch/powerpc/mm/ptdump/ptdump.c
> +++ b/arch/powerpc/mm/ptdump/ptdump.c
> @@ -334,12 +334,12 @@ static void walk_pagetables(struct pg_state *st)
>  	for (i = pgd_index(addr); i < PTRS_PER_PGD; i++, pgd++, addr += PGDIR_SIZE) {
>  		p4d_t *p4d = p4d_offset(pgd, 0);
>  
> -		if (pgd_none(*pgd) || pgd_is_leaf(*pgd))
> +		if (p4d_none(*p4d) || p4d_is_leaf(*p4d))
>  			note_page(st, addr, 1, p4d_val(*p4d), PGDIR_SIZE);
>  		else if (is_hugepd(__hugepd(p4d_val(*p4d))))
> -			walk_hugepd(st, (hugepd_t *)pgd, addr, PGDIR_SHIFT, 1);
> +			walk_hugepd(st, (hugepd_t *)p4d, addr, PGDIR_SHIFT, 1);
>  		else
> -			/* pgd exists */
> +			/* p4d exists */
>  			walk_pud(st, p4d, addr);
>  	}
>  }
>

I have put that in linux-next (for tomorrow) as a fix up for
powerpc-add-support-for-folded-p4d-page-tables.

-- 
Cheers,
Stephen Rothwell