2024-02-02 19:12:18

by Uladzislau Rezki

Subject: [PATCH 1/1] mm: vmalloc: Add a scan area of VA only once

Invoke a kmemleak_scan_area() function only for newly allocated
objects to add a scan area within that object. There is no reason
to add a same scan area(pointer to beginning or inside the object)
several times. If a VA is obtained from the cache its scan area
has already been associated.

Fixes: 7db166b4aa0d ("mm: vmalloc: offload free_vmap_area_lock lock")
Signed-off-by: Uladzislau Rezki (Sony) <[email protected]>
---
mm/vmalloc.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 449f45b0e474..25a8df497255 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1882,13 +1882,13 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,
va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
if (unlikely(!va))
return ERR_PTR(-ENOMEM);
- }

- /*
- * Only scan the relevant parts containing pointers to other objects
- * to avoid false negatives.
- */
- kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
+ /*
+ * Only scan the relevant parts containing pointers to other objects
+ * to avoid false negatives.
+ */
+ kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
+ }

retry:
if (addr == vend) {
--
2.39.2

2024-02-04 19:47:20

by Lorenzo Stoakes

Subject: Re: [PATCH 1/1] mm: vmalloc: Add a scan area of VA only once

On Fri, Feb 02, 2024 at 08:06:28PM +0100, Uladzislau Rezki (Sony) wrote:
> Invoke a kmemleak_scan_area() function only for newly allocated
> objects to add a scan area within that object. There is no reason
> to add a same scan area(pointer to beginning or inside the object)
> several times. If a VA is obtained from the cache its scan area
> has already been associated.
>
> Fixes: 7db166b4aa0d ("mm: vmalloc: offload free_vmap_area_lock lock")
> Signed-off-by: Uladzislau Rezki (Sony) <[email protected]>
> ---
> mm/vmalloc.c | 12 ++++++------
> 1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index 449f45b0e474..25a8df497255 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -1882,13 +1882,13 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,
> va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
> if (unlikely(!va))
> return ERR_PTR(-ENOMEM);
> - }
>
> - /*
> - * Only scan the relevant parts containing pointers to other objects
> - * to avoid false negatives.
> - */
> - kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
> + /*
> + * Only scan the relevant parts containing pointers to other objects
> + * to avoid false negatives.
> + */
> + kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
> + }
>
> retry:
> if (addr == vend) {
> --
> 2.39.2
>

Looks good to me, feel free to add:

Reviewed-by: Lorenzo Stoakes <[email protected]>

2024-02-05 06:41:40

by Christoph Hellwig

Subject: Re: [PATCH 1/1] mm: vmalloc: Add a scan area of VA only once

> + * Only scan the relevant parts containing pointers to other objects

Please avoid the overly long line.

The rest looks fine.

> + * to avoid false negatives.

2024-02-05 17:20:17

by Uladzislau Rezki

Subject: Re: [PATCH 1/1] mm: vmalloc: Add a scan area of VA only once

On Sun, Feb 04, 2024 at 10:41:13PM -0800, Christoph Hellwig wrote:
> > + * Only scan the relevant parts containing pointers to other objects
>
> Please avoid the overly long line.
>
> The rest looks fine.
>
> > + * to avoid false negatives.
>
Thanks!

--
Uladzislau Rezki

2024-02-05 17:22:01

by Uladzislau Rezki

Subject: Re: [PATCH 1/1] mm: vmalloc: Add a scan area of VA only once

On Sun, Feb 04, 2024 at 07:44:55PM +0000, Lorenzo Stoakes wrote:
> On Fri, Feb 02, 2024 at 08:06:28PM +0100, Uladzislau Rezki (Sony) wrote:
> > Invoke a kmemleak_scan_area() function only for newly allocated
> > objects to add a scan area within that object. There is no reason
> > to add a same scan area(pointer to beginning or inside the object)
> > several times. If a VA is obtained from the cache its scan area
> > has already been associated.
> >
> > Fixes: 7db166b4aa0d ("mm: vmalloc: offload free_vmap_area_lock lock")
> > Signed-off-by: Uladzislau Rezki (Sony) <[email protected]>
> > ---
> > mm/vmalloc.c | 12 ++++++------
> > 1 file changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> > index 449f45b0e474..25a8df497255 100644
> > --- a/mm/vmalloc.c
> > +++ b/mm/vmalloc.c
> > @@ -1882,13 +1882,13 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,
> > va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
> > if (unlikely(!va))
> > return ERR_PTR(-ENOMEM);
> > - }
> >
> > - /*
> > - * Only scan the relevant parts containing pointers to other objects
> > - * to avoid false negatives.
> > - */
> > - kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
> > + /*
> > + * Only scan the relevant parts containing pointers to other objects
> > + * to avoid false negatives.
> > + */
> > + kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
> > + }
> >
> > retry:
> > if (addr == vend) {
> > --
> > 2.39.2
> >
>
> Looks good to me, feel free to add:
>
> Reviewed-by: Lorenzo Stoakes <[email protected]>
>
Appreciate for review!

--
Uladzislau Rezki