Re: [syzbot] [ntfs3?] WARNING in indx_insert_into_buffer

[syzbot <syzbot+f9f8efb58a4db2ca98d0@syzkaller.appspotmail.com>]

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Subject: [ntfs3?] WARNING in indx_insert_into_buffer
Author: lizhi.xu@windriver.com

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git a379972973a8

diff --git a/net/core/page_pool_user.c b/net/core/page_pool_user.c
index 1426434a7e15..ca71f4103b3a 100644
--- a/net/core/page_pool_user.c
+++ b/net/core/page_pool_user.c
@@ -339,7 +339,8 @@ void page_pool_unlist(struct page_pool *pool)
 	mutex_lock(&page_pools_lock);
 	netdev_nl_page_pool_event(pool, NETDEV_CMD_PAGE_POOL_DEL_NTF);
 	xa_erase(&page_pools, pool->user.id);
-	hlist_del(&pool->user.list);
+	if (pool->slow.netdev)
+		hlist_del(&pool->user.list);
 	mutex_unlock(&page_pools_lock);
 }