FAILED: patch "[PATCH] f2fs: fix to reset all pinned status during fggc" failed to apply to 6.6-stable tree

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 2b8704b6a8b2896ccad1f5941d9a3e2c5031a470
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026090945-delicacy-nutmeg-a9dc@gregkh' --subject-prefix 'PATCH 6.6.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

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

From 2b8704b6a8b2896ccad1f5941d9a3e2c5031a470 Mon Sep 17 00:00:00 2001
From: Chao Yu <[email protected]>
Date: Mon, 17 Aug 2026 02:39:27 +0000
Subject: [PATCH] f2fs: fix to reset all pinned status during fggc

Otherwise, the pinned status may affect latter flow of fggc.

index 5917ee917d87..0c17038fcfd7 100644
@@ -2183,6 +2183,9 @@ int f2fs_gc_range(struct f2fs_sb_info *sbi,
 		do_garbage_collect(sbi, segno, &gc_list, FG_GC, true, false);
 		put_gc_inode(&gc_list);
 
+		/* reset all pinned status during fggc */
+		f2fs_unpin_all_sections(sbi, true);
+
 		if (!dry_run && get_valid_blocks(sbi, segno, true)) {
 			err = -EAGAIN;
 			goto next;

From: Chao Yu <[email protected]>

[ Upstream commit fa487f56efba6344aef67d871688f0908fe08af3 ]

It needs to trigger checkpoint to free space reclaimed by f2fs_gc_range(), otherwise, fallocate() on pinfile will fail easily even there is slash space in conventional zone.

[Testcase]
nullblk_create.sh 512 2 1024 1024
mkfs.f2fs /dev/nullb0 -f -m
mount /dev/nullb0 /mnt/f2fs/
touch /mnt/f2fs/pinfile
f2fs_io pinfile set /mnt/f2fs/pinfile
mkdir /mnt/f2fs/dir/
for((i=0;i<3934;i++)) do { dd if=/dev/zero of=/mnt/f2fs/dir/$i bs=1M count=1;} done sync
for((i=0;i<3934;i+=2)) do { rm /mnt/f2fs/dir/$i;} done for((i=0;i<1950;i++)) do { rm /mnt/f2fs/dir/$i;} done
sync
f2fs_io fallocate 0 0 $((1024*1024*1024)) /mnt/f2fs/pinfile
sync
stat /mnt/f2fs/pinfile
f2fs_io fiemap 0 $((1024*1024*1024)) /mnt/f2fs/pinfile

[Before]
fallocate failed: Resource temporarily unavailable
File: /mnt/f2fs/pinfile
Size: 109051904 Blocks: 213208 IO Block: 4096 regular file
Device: 250,0 Inode: 4 Links: 1
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2026-08-12 20:04:02.264000000 +0800
Modify: 2026-08-12 20:04:26.784000000 +0800
Change: 2026-08-12 20:04:26.784000000 +0800
Birth: -
root@localhost:~#
root@localhost:~#
root@localhost:~#

root@localhost:~# f2fs_io fiemap 0 $((1024*1024*1024)) /mnt/f2fs/pinfile
Fiemap: offset = 0 len = 1073741824
        logical addr.    physical addr.   length           flags
0       0000000000000000 0000000002e00000 0000000000200000 00001000
1       0000000000200000 000000002dc00000 0000000000400000 00001000
2       0000000000600000 000000002e400000 0000000000600000 00001000
3       0000000000c00000 000000007a400000 0000000005c00000 00001001

[After]
File: /mnt/f2fs/pinfile
Size: 1073741824 Blocks: 2099216 IO Block: 4096 regular file
Device: 250,0 Inode: 4 Links: 1
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2026-08-12 19:47:49.428000000 +0800
Modify: 2026-08-12 19:49:06.808000000 +0800
Change: 2026-08-12 19:49:06.808000000 +0800
Birth: -
Fiemap: offset = 0 len = 1073741824
logical addr. physical addr. length flags

0       0000000000000000 0000000002e00000 0000000000200000 00001000
1       0000000000200000 000000003aa00000 0000000000400000 00001000
2       0000000000600000 000000003b400000 0000000000200000 00001000
3       0000000000800000 000000007a200000 0000000005e00000 00001000
4       0000000006600000 0000000002800000 0000000000200000 00001000
5       0000000006800000 0000000003200000 0000000000400000 00001000
6       0000000006c00000 0000000003000000 0000000000200000 00001000
7       0000000006e00000 0000000003600000 0000000037200000 00001000
8       000000003e000000 000000003b200000 0000000000200000 00001000
9       000000003e200000 000000003a800000 0000000000200000 00001000
10      000000003e400000 000000003ae00000 0000000000400000 00001000
11      000000003e800000 000000003b600000 0000000001800000 00001001

Backport to 6.6: retain the existing gc_lock helpers and first-device GC range with its one-section reclaim request. Capture the GC result, return GC failures, and issue the checkpoint after releasing gc_lock before the single allocation retry. The newer lock-tracing and zone-range interfaces are not required for this fix.

Add braces around the existing -EAGAIN check in f2fs_gc_range(), without changing its behavior. This supplies the merge context needed to cherry-pick 2b8704b6a8b2896ccad1f5941d9a3e2c5031a470 cleanly on 6.6, without importing the upstream GC locking refactor or adding functions.

Stable-dep-of: 2b8704b6a8b2 ("f2fs: fix to reset all pinned status during fggc")

---
 fs/f2fs/gc.c      |  3 ++-
 fs/f2fs/segment.c | 13 +++++++++----
 2 files changed, 11 insertions(+), 5 deletions(-)

index ac21950f53cd2..f6ae5b086f44d 100644
@@ -2060,8 +2060,9 @@ int f2fs_gc_range(struct f2fs_sb_info *sbi,
 						dry_run_sections == 0);
 		put_gc_inode(&gc_list);
 
-		if (!dry_run && get_valid_blocks(sbi, segno, true))
+		if (!dry_run && get_valid_blocks(sbi, segno, true)) {
 			return -EAGAIN;
+		}
 		if (dry_run && dry_run_sections &&
 		    !get_valid_blocks(sbi, segno, true) && --gc_secs == 0)
 			break;

index 9c27353f384be..39a03fcb8e9d0 100644
@@ -3148,11 +3148,16 @@ int f2fs_allocate_pinning_section(struct f2fs_sb_info *sbi)
 
 	if (f2fs_sb_has_blkzoned(sbi) && err && gc_required) {
 		f2fs_down_write(&sbi->gc_lock);
-		f2fs_gc_range(sbi, 0, GET_SEGNO(sbi, FDEV(0).end_blk), true, 1);
+		err = f2fs_gc_range(sbi, 0, GET_SEGNO(sbi, FDEV(0).end_blk),
+				true, 1);
 		f2fs_up_write(&sbi->gc_lock);
-
-		gc_required = false;
-		goto retry;
+		if (err)
+			return err;
+		err = f2fs_sync_fs(sbi->sb, 1);
+		if (!err) {
+			gc_required = false;
+			goto retry;
+		}
 	}
 
 	return err;

2.53.0

From: Chao Yu <[email protected]>

[ Upstream commit 2b8704b6a8b2896ccad1f5941d9a3e2c5031a470 ]

Otherwise, the pinned status may affect latter flow of fggc.

---
 fs/f2fs/gc.c | 3 +++
 1 file changed, 3 insertions(+)

index f6ae5b086f44d..8759f0e013fe6 100644
@@ -2060,6 +2060,9 @@ int f2fs_gc_range(struct f2fs_sb_info *sbi,
 						dry_run_sections == 0);
 		put_gc_inode(&gc_list);
 
+		/* reset all pinned status during fggc */
+		f2fs_unpin_all_sections(sbi, true);
+
 		if (!dry_run && get_valid_blocks(sbi, segno, true)) {
 			return -EAGAIN;
 		}

2.53.0