This is a note to let you know that I've just added the patch titled ext2: fix missing percpu_counter_inc to the 5.4-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: ext2-fix-missing-percpu_counter_inc.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From bc2fbaa4d3808aef82dd1064a8e61c16549fe956 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka <mpatocka@xxxxxxxxxx> Date: Mon, 20 Apr 2020 16:02:21 -0400 Subject: ext2: fix missing percpu_counter_inc From: Mikulas Patocka <mpatocka@xxxxxxxxxx> commit bc2fbaa4d3808aef82dd1064a8e61c16549fe956 upstream. sbi->s_freeinodes_counter is only decreased by the ext2 code, it is never increased. This patch fixes it. Note that sbi->s_freeinodes_counter is only used in the algorithm that tries to find the group for new allocations, so this bug is not easily visible (the only visibility is that the group finding algorithm selects inoptinal result). Link: https://lore.kernel.org/r/alpine.LRH.2.02.2004201538300.19436@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/ext2/ialloc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/ext2/ialloc.c +++ b/fs/ext2/ialloc.c @@ -80,6 +80,7 @@ static void ext2_release_inode(struct su if (dir) le16_add_cpu(&desc->bg_used_dirs_count, -1); spin_unlock(sb_bgl_lock(EXT2_SB(sb), group)); + percpu_counter_inc(&EXT2_SB(sb)->s_freeinodes_counter); if (dir) percpu_counter_dec(&EXT2_SB(sb)->s_dirs_counter); mark_buffer_dirty(bh); @@ -528,7 +529,7 @@ got: goto fail; } - percpu_counter_add(&sbi->s_freeinodes_counter, -1); + percpu_counter_dec(&sbi->s_freeinodes_counter); if (S_ISDIR(mode)) percpu_counter_inc(&sbi->s_dirs_counter); Patches currently in stable-queue which might be from mpatocka@xxxxxxxxxx are queue-5.4/ext2-fix-missing-percpu_counter_inc.patch