Merge tag 'mm-hotfixes-stable-2024-07-26-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc hotfixes from Andrew Morton:
 "11 hotfixes, 7 of which are cc:stable.  7 are MM, 4 are other"

* tag 'mm-hotfixes-stable-2024-07-26-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  nilfs2: handle inconsistent state in nilfs_btnode_create_block()
  selftests/mm: skip test for non-LPA2 and non-LVA systems
  mm/page_alloc: fix pcp->count race between drain_pages_zone() vs __rmqueue_pcplist()
  mm: memcg: add cacheline padding after lruvec in mem_cgroup_per_node
  alloc_tag: outline and export free_reserved_page()
  decompress_bunzip2: fix rare decompression failure
  mm/huge_memory: avoid PMD-size page cache if needed
  mm: huge_memory: use !CONFIG_64BIT to relax huge page alignment on 32 bit machines
  mm: fix old/young bit handling in the faulting path
  dt-bindings: arm: update James Clark's email address
  MAINTAINERS: mailmap: update James Clark's email address

2 files changed, 22 insertions, 7 deletions

diff --git a/fs/nilfs2/btnode.c b/fs/nilfs2/btnode.c
index 0131d83b912d..c034080c334b 100644
--- a/fs/nilfs2/btnode.c
+++ b/fs/nilfs2/btnode.c
@@ -51,12 +51,21 @@ nilfs_btnode_create_block(struct address_space *btnc, __u64 blocknr)
 
 	bh = nilfs_grab_buffer(inode, btnc, blocknr, BIT(BH_NILFS_Node));
 	if (unlikely(!bh))
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	if (unlikely(buffer_mapped(bh) || buffer_uptodate(bh) ||
 		     buffer_dirty(bh))) {
-		brelse(bh);
-		BUG();
+		/*
+		 * The block buffer at the specified new address was already
+		 * in use.  This can happen if it is a virtual block number
+		 * and has been reallocated due to corruption of the bitmap
+		 * used to manage its allocation state (if not, the buffer
+		 * clearing of an abandoned b-tree node is missing somewhere).
+		 */
+		nilfs_error(inode->i_sb,
+			    "state inconsistency probably due to duplicate use of b-tree node block address %llu (ino=%lu)",
+			    (unsigned long long)blocknr, inode->i_ino);
+		goto failed;
 	}
 	memset(bh->b_data, 0, i_blocksize(inode));
 	bh->b_bdev = inode->i_sb->s_bdev;
@@ -67,6 +76,12 @@ nilfs_btnode_create_block(struct address_space *btnc, __u64 blocknr)
 	folio_unlock(bh->b_folio);
 	folio_put(bh->b_folio);
 	return bh;
+
+failed:
+	folio_unlock(bh->b_folio);
+	folio_put(bh->b_folio);
+	brelse(bh);
+	return ERR_PTR(-EIO);
 }
 
 int nilfs_btnode_submit_block(struct address_space *btnc, __u64 blocknr,
@@ -217,8 +232,8 @@ retry:
 	}
 
 	nbh = nilfs_btnode_create_block(btnc, newkey);
-	if (!nbh)
-		return -ENOMEM;
+	if (IS_ERR(nbh))
+		return PTR_ERR(nbh);
 
 	BUG_ON(nbh == obh);
 	ctxt->newbh = nbh;
diff --git a/fs/nilfs2/btree.c b/fs/nilfs2/btree.c
index a139970e4804..862bdf23120e 100644
--- a/fs/nilfs2/btree.c
+++ b/fs/nilfs2/btree.c
@@ -63,8 +63,8 @@ static int nilfs_btree_get_new_block(const struct nilfs_bmap *btree,
 	struct buffer_head *bh;
 
 	bh = nilfs_btnode_create_block(btnc, ptr);
-	if (!bh)
-		return -ENOMEM;
+	if (IS_ERR(bh))
+		return PTR_ERR(bh);
 
 	set_buffer_nilfs_volatile(bh);
 	*bhp = bh;