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

From: Davidlohr Bueso <[email-masked]>
Date: Thu, 06 Nov 2014 01:09:41 -0800

On Thu, 2014-11-06 at 16:44 +1100, Stephen Rothwell wrote:
> Hi Andrew,
> 
> After merging the akpm-current tree, today's linux-next build (powerpc
> ppc64_defconfig) failed like this:
> 
> mm/fremap.c: In function 'SYSC_remap_file_pages':
> mm/fremap.c:241:22: error: 'struct address_space' has no member named 'i_mmap_mutex'
>    mutex_lock(&mapping->i_mmap_mutex);
>                       ^
> mm/fremap.c:247:24: error: 'struct address_space' has no member named 'i_mmap_mutex'
>    mutex_unlock(&mapping->i_mmap_mutex);
>                         ^
> 
> Caused by commit 1f8c97e79f66 ("mm: convert i_mmap_mutex to rwsem").
> 
> I applied this patch for today (not sure if there is a better way):
> 
> From: Stephen Rothwell <[email-masked]>
> Date: Thu, 6 Nov 2014 16:26:41 +1100
> Subject: [PATCH] mm: convert i_mmap_mutex to rwsem fix
> 
> Signed-off-by: Stephen Rothwell <[email-masked]>
> ---
>  mm/fremap.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/fremap.c b/mm/fremap.c
> index 9129013732d7..2805d71cf476 100644
> --- a/mm/fremap.c
> +++ b/mm/fremap.c
> @@ -238,13 +238,13 @@ get_write_lock:
>  			}
>  			goto out_freed;
>  		}
> -		mutex_lock(&mapping->i_mmap_mutex);
> +		i_mmap_lock_write(mapping);

That's the correct fix, thanks. However, I had particularly dropped that
modification because linux-next no longer even has mm/fremap.c so I'm
not sure what went wrong here...