FAILED: patch "[PATCH] mm, slab: restore NUMA policy support for large kmalloc" failed to apply to 6.1-stable tree

FAILED: patch "[PATCH] mm, slab: restore NUMA policy support for large kmalloc" failed to apply to 6.1-stable tree

[gregkh]

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x e2d18cbf178775ad377ad88ee55e6e183c38d262
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025081818-skilled-timid-4660@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From e2d18cbf178775ad377ad88ee55e6e183c38d262 Mon Sep 17 00:00:00 2001
From: Vlastimil Babka <vbabka@suse.cz>
Date: Mon, 2 Jun 2025 13:02:12 +0200
Subject: [PATCH] mm, slab: restore NUMA policy support for large kmalloc

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()")
Cc: <stable@vger.kernel.org>
Acked-by: Christoph Lameter (Ampere) <cl@gentwo.org>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

diff --git a/mm/slub.c b/mm/slub.c
index 31e11ef256f9..06d64a5fb1bf 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -4269,7 +4269,12 @@ 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,

Re: FAILED: patch "[PATCH] mm, slab: restore NUMA policy support for large kmalloc" failed to apply to 6.1-stable tree

[Christoph Lameter (Ampere)]

The breakage was introduced in 6.1 So maybe the fix is not needed?

On Mon, 18 Aug 2025, gregkh@linuxfoundation.org wrote:

>
> The patch below does not apply to the 6.1-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@vger.kernel.org>.
>
> To reproduce the conflict and resubmit, you may use the following commands:
>
> git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
> git checkout FETCH_HEAD
> git cherry-pick -x e2d18cbf178775ad377ad88ee55e6e183c38d262
> # <resolve conflicts, build, test, etc.>
> git commit -s
> git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025081818-skilled-timid-4660@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
>
> Possible dependencies:
>
>
>
> thanks,
>
> greg k-h
>
> ------------------ original commit in Linus's tree ------------------
>
> >From e2d18cbf178775ad377ad88ee55e6e183c38d262 Mon Sep 17 00:00:00 2001
> From: Vlastimil Babka <vbabka@suse.cz>
> Date: Mon, 2 Jun 2025 13:02:12 +0200
> Subject: [PATCH] mm, slab: restore NUMA policy support for large kmalloc
>
> 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()")
> Cc: <stable@vger.kernel.org>
> Acked-by: Christoph Lameter (Ampere) <cl@gentwo.org>
> Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
> Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
>
> diff --git a/mm/slub.c b/mm/slub.c
> index 31e11ef256f9..06d64a5fb1bf 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -4269,7 +4269,12 @@ 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,
>

Re: FAILED: patch "[PATCH] mm, slab: restore NUMA policy support for large kmalloc" failed to apply to 6.1-stable tree

[Greg KH]

On Mon, Aug 18, 2025 at 08:07:30AM -0700, Christoph Lameter (Ampere) wrote:
> The breakage was introduced in 6.1 So maybe the fix is not needed?

If it is broken in 6.1, then yes, it needs to be fixed in 6.1.y :)

thanks,

greg k-h