On Fri, Mar 20, 2020 at 09:37:18AM +0100, Vlastimil Babka wrote:

On 3/20/20 4:42 AM, Bharata B Rao wrote:

quoted

On Thu, Mar 19, 2020 at 02:47:58PM +0100, Vlastimil Babka wrote:

quoted

diff --git a/mm/slub.c b/mm/slub.c
index 17dc00e33115..7113b1f9cd77 100644
--- a/mm/slub.c
+++ b/mm/slub.c

@@ -1973,8 +1973,6 @@ static void *get_partial(struct kmem_cache *s, gfp_t flags, int node,
 
 	if (node == NUMA_NO_NODE)
 		searchnode = numa_mem_id();
-	else if (!node_present_pages(node))
-		searchnode = node_to_mem_node(node);
 
 	object = get_partial_node(s, get_node(s, searchnode), c, flags);
 	if (object || node != NUMA_NO_NODE)

@@ -2563,17 +2561,27 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 	struct page *page;
 
 	page = c->page;
-	if (!page)
+	if (!page) {
+		/*
+		 * if the node is not online or has no normal memory, just
+		 * ignore the node constraint
+		 */
+		if (unlikely(node != NUMA_NO_NODE &&
+			     !node_state(node, N_NORMAL_MEMORY)))
+			node = NUMA_NO_NODE;
 		goto new_slab;
+	}
 redo:
 
 	if (unlikely(!node_match(page, node))) {
-		int searchnode = node;
-
-		if (node != NUMA_NO_NODE && !node_present_pages(node))
-			searchnode = node_to_mem_node(node);
-
-		if (unlikely(!node_match(page, searchnode))) {
+		/*
+		 * same as above but node_match() being false already
+		 * implies node != NUMA_NO_NODE
+		 */
+		if (!node_state(node, N_NORMAL_MEMORY)) {
+			node = NUMA_NO_NODE;
+			goto redo;
+		} else {
 			stat(s, ALLOC_NODE_MISMATCH);
 			deactivate_slab(s, page, c->freelist, c);
 			goto new_slab;

This fixes the problem I reported at
https://lore.kernel.org/linux-mm/20200317092624.GB22538@in.ibm.com/ (local)

Thanks, I hope it means I can make it Reported-and-tested-by: you

It was reeported first by PUVICHAKRAVARTHY RAMACHANDRAN [off-list ref]
You can add my tested-by.

Regards,
Bharata.