+ mm-migrate-move-numa-hinting-fault-folio-isolation-checks-under-ptl-fix.patch added to mm-unstable branch

The patch titled
Subject: mm-migrate-move-numa-hinting-fault-folio-isolation-checks-under-ptl-fix
has been added to the -mm mm-unstable branch. Its filename is
mm-migrate-move-numa-hinting-fault-folio-isolation-checks-under-ptl-fix.patch

This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-migrate-move-numa-hinting-fault-folio-isolation-checks-under-ptl-fix.patch

This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: David Hildenbrand <[email protected]>
Subject: mm-migrate-move-numa-hinting-fault-folio-isolation-checks-under-ptl-fix
Date: Wed, 26 Jun 2024 18:14:44 +0200

Donet reports an issue during NUMA migration we haven't seen previously:

	[   71.422804] list_del corruption, c00c00000061b3c8->next is
	LIST_POISON1 (5deadbeef0000100)
	[   71.422839] ------------[ cut here ]------------
	[   71.422843] kernel BUG at lib/list_debug.c:56!
	[   71.422850] Oops: Exception in kernel mode, sig: 5 [#1]

We forgot to convert one "return 0;" to return an error instead from migrate_misplaced_folio_prepare() in case the target node is nearly full.

---

 mm/migrate.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -2564,7 +2564,7 @@ int migrate_misplaced_folio_prepare(stru
 		int z;
 
 		if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING))
-			return 0;
+			return -EAGAIN;
 		for (z = pgdat->nr_zones - 1; z >= 0; z--) {
 			if (managed_zone(pgdat->node_zones + z))
 				break;

_

Patches currently in -mm which might be from [email protected] are

mm-update-_mapcount-and-page_type-documentation.patch mm-allow-reuse-of-the-lower-16-bit-of-the-page-type-with-an-actual-type.patch mm-zsmalloc-use-a-proper-page-type.patch mm-page_alloc-clear-pagebuddy-using-__clearpagebuddy-for-bad-pages.patch mm-filemap-reinitialize-folio-_mapcount-directly.patch mm-mm_init-initialize-page-_mapcount-directly-in-__init_single_page.patch mm-pass-meminit_context-to-__free_pages_core.patch mm-pass-meminit_context-to-__free_pages_core-fix.patch mm-pass-meminit_context-to-__free_pages_core-fix-2.patch mm-pass-meminit_context-to-__free_pages_core-fix-3.patch mm-memory_hotplug-initialize-memmap-of-zone_device-with-pageoffline-instead-of-pagereserved.patch mm-memory_hotplug-skip-adjust_managed_page_count-for-pageoffline-pages-when-offlining.patch mm-read-page_type-using-read_once.patch mm-migrate-make-migrate_misplaced_folio-return-0-on-success.patch mm-migrate-move-numa-hinting-fault-folio-isolation-checks-under-ptl.patch mm-migrate-move-numa-hinting-fault-folio-isolation-checks-under-ptl-fix.patch