The patch below does not apply to the 4.9-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 stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 30928e9baac238a7330085a1c5747f0b5df444b4 Mon Sep 17 00:00:00 2001
From: Josef Bacik josef@toxicpanda.com Date: Thu, 11 Oct 2018 15:54:31 -0400 Subject: [PATCH] btrfs: don't run delayed_iputs in commit
This could result in a really bad case where we do something like
evict evict_refill_and_join btrfs_commit_transaction btrfs_run_delayed_iputs evict evict_refill_and_join btrfs_commit_transaction ... forever
We have plenty of other places where we run delayed iputs that are much safer, let those do the work.
CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana fdmanana@suse.com Signed-off-by: Josef Bacik josef@toxicpanda.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 5686290a50e1..d1eeef9ec5da 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -2283,15 +2283,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans)
kmem_cache_free(btrfs_trans_handle_cachep, trans);
- /* - * If fs has been frozen, we can not handle delayed iputs, otherwise - * it'll result in deadlock about SB_FREEZE_FS. - */ - if (current != fs_info->transaction_kthread && - current != fs_info->cleaner_kthread && - !test_bit(BTRFS_FS_FROZEN, &fs_info->flags)) - btrfs_run_delayed_iputs(fs_info); - return ret;
scrub_continue: