This is a note to let you know that I've just added the patch titled f2fs: don't get FREEZE lock in f2fs_evict_inode in frozen fs to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: f2fs-don-t-get-freeze-lock-in-f2fs_evict_inode-in-fr.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 564e865019aa9e8200dd53ab3d05050801ba36af Author: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> Date: Fri Mar 4 09:40:05 2022 -0800 f2fs: don't get FREEZE lock in f2fs_evict_inode in frozen fs [ Upstream commit ba900534f807f0b327c92d5141c85d2313e2d55c ] Let's purge inode cache in order to avoid the below deadlock. [freeze test] shrinkder freeze_super - pwercpu_down_write(SB_FREEZE_FS) - super_cache_scan - down_read(&sb->s_umount) - prune_icache_sb - dispose_list - evict - f2fs_evict_inode thaw_super - down_write(&sb->s_umount); - __percpu_down_read(SB_FREEZE_FS) Reviewed-by: Chao Yu <chao@xxxxxxxxxx> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs index f627e705e663..48d41b669627 100644 --- a/Documentation/ABI/testing/sysfs-fs-f2fs +++ b/Documentation/ABI/testing/sysfs-fs-f2fs @@ -425,6 +425,7 @@ Description: Show status of f2fs superblock in real time. 0x800 SBI_QUOTA_SKIP_FLUSH skip flushing quota in current CP 0x1000 SBI_QUOTA_NEED_REPAIR quota file may be corrupted 0x2000 SBI_IS_RESIZEFS resizefs is in process + 0x4000 SBI_IS_FREEZING freefs is in process ====== ===================== ================================= What: /sys/fs/f2fs/<disk>/ckpt_thread_ioprio diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c index 8c50518475a9..07ad0d81f0c5 100644 --- a/fs/f2fs/debug.c +++ b/fs/f2fs/debug.c @@ -338,6 +338,7 @@ static char *s_flag[] = { [SBI_QUOTA_SKIP_FLUSH] = " quota_skip_flush", [SBI_QUOTA_NEED_REPAIR] = " quota_need_repair", [SBI_IS_RESIZEFS] = " resizefs", + [SBI_IS_FREEZING] = " freezefs", }; static int stat_show(struct seq_file *s, void *v) diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index c68817d83a53..0a0fa1a64d06 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -1253,6 +1253,7 @@ enum { SBI_QUOTA_SKIP_FLUSH, /* skip flushing quota in current CP */ SBI_QUOTA_NEED_REPAIR, /* quota file may be corrupted */ SBI_IS_RESIZEFS, /* resizefs is in process */ + SBI_IS_FREEZING, /* freezefs is in process */ }; enum { diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index 6488f5ff250c..2272000fb10b 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -769,7 +769,8 @@ void f2fs_evict_inode(struct inode *inode) f2fs_remove_ino_entry(sbi, inode->i_ino, UPDATE_INO); f2fs_remove_ino_entry(sbi, inode->i_ino, FLUSH_INO); - sb_start_intwrite(inode->i_sb); + if (!is_sbi_flag_set(sbi, SBI_IS_FREEZING)) + sb_start_intwrite(inode->i_sb); set_inode_flag(inode, FI_NO_ALLOC); i_size_write(inode, 0); retry: @@ -800,7 +801,8 @@ void f2fs_evict_inode(struct inode *inode) if (dquot_initialize_needed(inode)) set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR); } - sb_end_intwrite(inode->i_sb); + if (!is_sbi_flag_set(sbi, SBI_IS_FREEZING)) + sb_end_intwrite(inode->i_sb); no_delete: dquot_drop(inode); diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 7b744ceb17a5..6dc66b7bc1f5 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -1663,11 +1663,15 @@ static int f2fs_freeze(struct super_block *sb) /* ensure no checkpoint required */ if (!llist_empty(&F2FS_SB(sb)->cprc_info.issue_list)) return -EINVAL; + + /* to avoid deadlock on f2fs_evict_inode->SB_FREEZE_FS */ + set_sbi_flag(F2FS_SB(sb), SBI_IS_FREEZING); return 0; } static int f2fs_unfreeze(struct super_block *sb) { + clear_sbi_flag(F2FS_SB(sb), SBI_IS_FREEZING); return 0; }