[PATCH v2] mm: Release a semaphore in 'get_vaddr_frames()'

[PATCH v2] mm: Release a semaphore in 'get_vaddr_frames()'

[Christophe JAILLET]

A semaphore is acquired before this check, so we must release it before
leaving.

Fixes: b7f0554a56f2 ("mm: fail get_vaddr_frames() for filesystem-dax mappings")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
-- Untested --

v1 -> v2: 'goto out' instead of duplicating code
---
 mm/frame_vector.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/mm/frame_vector.c b/mm/frame_vector.c
index 297c7238f7d4..c64dca6e27c2 100644
--- a/mm/frame_vector.c
+++ b/mm/frame_vector.c
@@ -62,8 +62,10 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
 	 * get_user_pages_longterm() and disallow it for filesystem-dax
 	 * mappings.
 	 */
-	if (vma_is_fsdax(vma))
-		return -EOPNOTSUPP;
+	if (vma_is_fsdax(vma)) {
+		ret = -EOPNOTSUPP;
+		goto out;
+	}
 
 	if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
 		vec->got_ref = true;
-- 
2.14.1

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [PATCH v2] mm: Release a semaphore in 'get_vaddr_frames()'

[Michal Hocko]

On Mon 11-12-17 22:10:09, Christophe JAILLET wrote:
> A semaphore is acquired before this check, so we must release it before
> leaving.
> 
> Fixes: b7f0554a56f2 ("mm: fail get_vaddr_frames() for filesystem-dax mappings")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

Looks good to me now.
Acked-by: Michal Hocko <mhocko@suse.com>

Thanks

> ---
> -- Untested --
> 
> v1 -> v2: 'goto out' instead of duplicating code
> ---
>  mm/frame_vector.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/frame_vector.c b/mm/frame_vector.c
> index 297c7238f7d4..c64dca6e27c2 100644
> --- a/mm/frame_vector.c
> +++ b/mm/frame_vector.c
> @@ -62,8 +62,10 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
>  	 * get_user_pages_longterm() and disallow it for filesystem-dax
>  	 * mappings.
>  	 */
> -	if (vma_is_fsdax(vma))
> -		return -EOPNOTSUPP;
> +	if (vma_is_fsdax(vma)) {
> +		ret = -EOPNOTSUPP;
> +		goto out;
> +	}
>  
>  	if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
>  		vec->got_ref = true;
> -- 
> 2.14.1
> 

-- 
Michal Hocko
SUSE Labs

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>