The slab allocator observes the task's NUMA policy in various places
such as allocating slab pages. Large kmalloc() allocations used to do
that too, until an unintended change by c4cab557521a ("mm/slab_common:
cleanup kmalloc_large()") resulted in ignoring mempolicy and just
preferring the local node. Restore the NUMA policy support.

Fixes: c4cab557521a ("mm/slab_common: cleanup kmalloc_large()")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
---
 mm/slub.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/mm/slub.c b/mm/slub.c
index dc9e729e1d269b5d362cb5bc44f824640ffd00f3..11356c701f9f857a2e8cf40bf963ac3abdb5e010 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -4282,7 +4282,12 @@ static void *___kmalloc_large_node(size_t size, gfp_t flags, int node)
 		flags = kmalloc_fix_flags(flags);
 
 	flags |= __GFP_COMP;
-	folio = (struct folio *)alloc_pages_node_noprof(node, flags, order);
+
+	if (node == NUMA_NO_NODE)
+		folio = (struct folio *)alloc_pages_noprof(flags, order);
+	else
+		folio = (struct folio *)__alloc_pages_noprof(flags, order, node, NULL);
+
 	if (folio) {
 		ptr = folio_address(folio);
 		lruvec_stat_mod_folio(folio, NR_SLAB_UNRECLAIMABLE_B,

-- 
2.49.0

On Mon, Jun 02, 2025 at 01:02:12PM +0200, Vlastimil Babka wrote:
> The slab allocator observes the task's NUMA policy in various places
> such as allocating slab pages. Large kmalloc() allocations used to do
> that too, until an unintended change by c4cab557521a ("mm/slab_common:
> cleanup kmalloc_large()") resulted in ignoring mempolicy and just
> preferring the local node. Restore the NUMA policy support.
> 
> Fixes: c4cab557521a ("mm/slab_common: cleanup kmalloc_large()")

Oops, I broke it unintentionally :(

> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
> ---

Reviewed-by: Harry Yoo <harry.yoo@oracle.com>

Thanks for fixing!

-- 
Cheers,
Harry / Hyeonggon

>  mm/slub.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/mm/slub.c b/mm/slub.c
> index dc9e729e1d269b5d362cb5bc44f824640ffd00f3..11356c701f9f857a2e8cf40bf963ac3abdb5e010 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -4282,7 +4282,12 @@ static void *___kmalloc_large_node(size_t size, gfp_t flags, int node)
>  		flags = kmalloc_fix_flags(flags);
>  
>  	flags |= __GFP_COMP;
> -	folio = (struct folio *)alloc_pages_node_noprof(node, flags, order);
> +
> +	if (node == NUMA_NO_NODE)
> +		folio = (struct folio *)alloc_pages_noprof(flags, order);
> +	else
> +		folio = (struct folio *)__alloc_pages_noprof(flags, order, node, NULL);
> +
>  	if (folio) {
>  		ptr = folio_address(folio);
>  		lruvec_stat_mod_folio(folio, NR_SLAB_UNRECLAIMABLE_B,
> 
> -- 
> 2.49.0

Vlastimil Babka <vbabka@suse.cz> writes:

> The slab allocator observes the task's NUMA policy in various places
> such as allocating slab pages. Large kmalloc() allocations used to do
> that too, until an unintended change by c4cab557521a ("mm/slab_common:
> cleanup kmalloc_large()") resulted in ignoring mempolicy and just
> preferring the local node. Restore the NUMA policy support.
>
> Fixes: c4cab557521a ("mm/slab_common: cleanup kmalloc_large()")
> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

Acked-by: Roman Gushchin <roman.gushchin@linux.dev>

Thanks!

On Mon, 2 Jun 2025, Vlastimil Babka wrote:

> The slab allocator observes the task's NUMA policy in various places
> such as allocating slab pages. Large kmalloc() allocations used to do
> that too, until an unintended change by c4cab557521a ("mm/slab_common:
> cleanup kmalloc_large()") resulted in ignoring mempolicy and just
> preferring the local node. Restore the NUMA policy support.

Acked-by: Christoph Lameter (Ampere) <cl@gentwo.org>