diff options
author | Naohiro Aota <naohiro.aota@wdc.com> | 2023-12-22 07:56:34 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-02-01 03:19:05 +0300 |
commit | 6f74989f5909cdec9b1274641f0fa306b15bb476 (patch) | |
tree | 662a1246c48757f0821d5eabced82e5774acdd97 /fs/btrfs | |
parent | 642b9c520ef2f104277ad1f902f8526edbe087fb (diff) | |
download | linux-6f74989f5909cdec9b1274641f0fa306b15bb476.tar.xz |
btrfs: zoned: fix lock ordering in btrfs_zone_activate()
commit b18f3b60b35a8c01c9a2a0f0d6424c6d73971dc3 upstream.
The btrfs CI reported a lockdep warning as follows by running generic
generic/129.
WARNING: possible circular locking dependency detected
6.7.0-rc5+ #1 Not tainted
------------------------------------------------------
kworker/u5:5/793427 is trying to acquire lock:
ffff88813256d028 (&cache->lock){+.+.}-{2:2}, at: btrfs_zone_finish_one_bg+0x5e/0x130
but task is already holding lock:
ffff88810a23a318 (&fs_info->zone_active_bgs_lock){+.+.}-{2:2}, at: btrfs_zone_finish_one_bg+0x34/0x130
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&fs_info->zone_active_bgs_lock){+.+.}-{2:2}:
...
-> #0 (&cache->lock){+.+.}-{2:2}:
...
This is because we take fs_info->zone_active_bgs_lock after a block_group's
lock in btrfs_zone_activate() while doing the opposite in other places.
Fix the issue by expanding the fs_info->zone_active_bgs_lock's critical
section and taking it before a block_group's lock.
Fixes: a7e1ac7bdc5a ("btrfs: zoned: reserve zones for an active metadata/system block group")
CC: stable@vger.kernel.org # 6.6
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/btrfs')
-rw-r--r-- | fs/btrfs/zoned.c | 8 |
1 files changed, 2 insertions, 6 deletions
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c index 09bc325d075d..41a8cdce5d9f 100644 --- a/fs/btrfs/zoned.c +++ b/fs/btrfs/zoned.c @@ -1975,6 +1975,7 @@ bool btrfs_zone_activate(struct btrfs_block_group *block_group) map = block_group->physical_map; + spin_lock(&fs_info->zone_active_bgs_lock); spin_lock(&block_group->lock); if (test_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &block_group->runtime_flags)) { ret = true; @@ -1987,7 +1988,6 @@ bool btrfs_zone_activate(struct btrfs_block_group *block_group) goto out_unlock; } - spin_lock(&fs_info->zone_active_bgs_lock); for (i = 0; i < map->num_stripes; i++) { struct btrfs_zoned_device_info *zinfo; int reserved = 0; @@ -2007,20 +2007,17 @@ bool btrfs_zone_activate(struct btrfs_block_group *block_group) */ if (atomic_read(&zinfo->active_zones_left) <= reserved) { ret = false; - spin_unlock(&fs_info->zone_active_bgs_lock); goto out_unlock; } if (!btrfs_dev_set_active_zone(device, physical)) { /* Cannot activate the zone */ ret = false; - spin_unlock(&fs_info->zone_active_bgs_lock); goto out_unlock; } if (!is_data) zinfo->reserved_active_zones--; } - spin_unlock(&fs_info->zone_active_bgs_lock); /* Successfully activated all the zones */ set_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &block_group->runtime_flags); @@ -2028,8 +2025,6 @@ bool btrfs_zone_activate(struct btrfs_block_group *block_group) /* For the active block group list */ btrfs_get_block_group(block_group); - - spin_lock(&fs_info->zone_active_bgs_lock); list_add_tail(&block_group->active_bg_list, &fs_info->zone_active_bgs); spin_unlock(&fs_info->zone_active_bgs_lock); @@ -2037,6 +2032,7 @@ bool btrfs_zone_activate(struct btrfs_block_group *block_group) out_unlock: spin_unlock(&block_group->lock); + spin_unlock(&fs_info->zone_active_bgs_lock); return ret; } |