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FAILED: patch "[PATCH] ext4: always allocate blocks only from groups inode can use" failed to apply to 6.6-stable tree

PATCH New [email protected] 2 participants 2 messages Feb 24 – Feb 25

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author maintainer
#0 lore raw

The patch below does not apply to the 6.6-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 <[email protected]>.

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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 4865c768b563deff1b6a6384e74a62f143427b42
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026022434-hazelnut-twistable-eb07@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

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

From 4865c768b563deff1b6a6384e74a62f143427b42 Mon Sep 17 00:00:00 2001
From: Jan Kara <[email protected]>
Date: Wed, 14 Jan 2026 19:28:18 +0100
Subject: [PATCH] ext4: always allocate blocks only from groups inode can use

For filesystems with more than 2^32 blocks inodes using indirect block based format cannot use blocks beyond the 32-bit limit. ext4_mb_scan_groups_linear() takes care to not select these unsupported groups for such inodes however other functions selecting groups for allocation don't. So far this is harmless because the other selection functions are used only with mb_optimize_scan and this is currently disabled for inodes with indirect blocks however in the following patch we want to enable mb_optimize_scan regardless of inode format.

fs/ext4/mballoc.c +20 -9
index dd29558ad753..910b454b4a21 100644
@@ -892,6 +892,21 @@ mb_update_avg_fragment_size(struct super_block *sb, struct ext4_group_info *grp)
 	}
 }
 
+static ext4_group_t ext4_get_allocation_groups_count(
+				struct ext4_allocation_context *ac)
+{
+	ext4_group_t ngroups = ext4_get_groups_count(ac->ac_sb);
+
+	/* non-extent files are limited to low blocks/groups */
+	if (!(ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS)))
+		ngroups = EXT4_SB(ac->ac_sb)->s_blockfile_groups;
+
+	/* Pairs with smp_wmb() in ext4_update_super() */
+	smp_rmb();
+
+	return ngroups;
+}
+
 static int ext4_mb_scan_groups_xa_range(struct ext4_allocation_context *ac,
 					struct xarray *xa,
 					ext4_group_t start, ext4_group_t end)
@@ -899,7 +914,7 @@ static int ext4_mb_scan_groups_xa_range(struct ext4_allocation_context *ac,
 	struct super_block *sb = ac->ac_sb;
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
 	enum criteria cr = ac->ac_criteria;
-	ext4_group_t ngroups = ext4_get_groups_count(sb);
+	ext4_group_t ngroups = ext4_get_allocation_groups_count(ac);
 	unsigned long group = start;
 	struct ext4_group_info *grp;
 
@@ -951,7 +966,7 @@ static int ext4_mb_scan_groups_p2_aligned(struct ext4_allocation_context *ac,
 	ext4_group_t start, end;
 
 	start = group;
-	end = ext4_get_groups_count(ac->ac_sb);
+	end = ext4_get_allocation_groups_count(ac);
 wrap_around:
 	for (i = ac->ac_2order; i < MB_NUM_ORDERS(ac->ac_sb); i++) {
 		ret = ext4_mb_scan_groups_largest_free_order_range(ac, i,
@@ -1001,7 +1016,7 @@ static int ext4_mb_scan_groups_goal_fast(struct ext4_allocation_context *ac,
 	ext4_group_t start, end;
 
 	start = group;
-	end = ext4_get_groups_count(ac->ac_sb);
+	end = ext4_get_allocation_groups_count(ac);
 wrap_around:
 	i = mb_avg_fragment_size_order(ac->ac_sb, ac->ac_g_ex.fe_len);
 	for (; i < MB_NUM_ORDERS(ac->ac_sb); i++) {
@@ -1083,7 +1098,7 @@ static int ext4_mb_scan_groups_best_avail(struct ext4_allocation_context *ac,
 		min_order = fls(ac->ac_o_ex.fe_len);
 
 	start = group;
-	end = ext4_get_groups_count(ac->ac_sb);
+	end = ext4_get_allocation_groups_count(ac);
 wrap_around:
 	for (i = order; i >= min_order; i--) {
 		int frag_order;
@@ -1182,11 +1197,7 @@ static int ext4_mb_scan_groups(struct ext4_allocation_context *ac)
 	int ret = 0;
 	ext4_group_t start;
 	struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb);
-	ext4_group_t ngroups = ext4_get_groups_count(ac->ac_sb);
-
-	/* non-extent files are limited to low blocks/groups */
-	if (!(ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS)))
-		ngroups = sbi->s_blockfile_groups;
+	ext4_group_t ngroups = ext4_get_allocation_groups_count(ac);
 
 	/* searching for the right group start from the goal value specified */
 	start = ac->ac_g_ex.fe_group;
maintainer
#1 lore raw

PATCH 1/1 ext4: always allocate blocks only from groups inode can use

From: Jan Kara <[email protected]>

[ Upstream commit 4865c768b563deff1b6a6384e74a62f143427b42 ]

For filesystems with more than 2^32 blocks inodes using indirect block based format cannot use blocks beyond the 32-bit limit. ext4_mb_scan_groups_linear() takes care to not select these unsupported groups for such inodes however other functions selecting groups for allocation don't. So far this is harmless because the other selection functions are used only with mb_optimize_scan and this is currently disabled for inodes with indirect blocks however in the following patch we want to enable mb_optimize_scan regardless of inode format.

---
 fs/ext4/mballoc.c | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)
fs/ext4/mballoc.c +16 -4
index 5ba161bd66a3e..44a16895f76a2 100644
@@ -883,6 +883,21 @@ mb_update_avg_fragment_size(struct super_block *sb, struct ext4_group_info *grp)
 	}
 }
 
+static ext4_group_t ext4_get_allocation_groups_count(
+				struct ext4_allocation_context *ac)
+{
+	ext4_group_t ngroups = ext4_get_groups_count(ac->ac_sb);
+
+	/* non-extent files are limited to low blocks/groups */
+	if (!(ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS)))
+		ngroups = EXT4_SB(ac->ac_sb)->s_blockfile_groups;
+
+	/* Pairs with smp_wmb() in ext4_update_super() */
+	smp_rmb();
+
+	return ngroups;
+}
+
 /*
  * Choose next group by traversing largest_free_order lists. Updates *new_cr if
  * cr level needs an update.
@@ -2816,10 +2831,7 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
 
 	sb = ac->ac_sb;
 	sbi = EXT4_SB(sb);
-	ngroups = ext4_get_groups_count(sb);
-	/* non-extent files are limited to low blocks/groups */
-	if (!(ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS)))
-		ngroups = sbi->s_blockfile_groups;
+	ngroups = ext4_get_allocation_groups_count(ac);
 
 	BUG_ON(ac->ac_status == AC_STATUS_FOUND);
 
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