bisecting fixing commit since 34816d20f173a90389c8a7e641166d8ea9dce70a
building syzkaller on e6b0d3140b98e8456fbd089d584e932e19257d94
testing commit 34816d20f173a90389c8a7e641166d8ea9dce70a with gcc (GCC) 10.2.1 20210217
kernel signature: 509e65a0c333249946868fd4ce178dc7785d6be7afc8f228dc7f56a33427edc5
all runs: crashed: INFO: task hung in sync_inodes_sb
testing current HEAD dd860052c99b1e088352bdd4fb7aef46f8d2ef47
testing commit dd860052c99b1e088352bdd4fb7aef46f8d2ef47 with gcc (GCC) 10.2.1 20210217
kernel signature: f779055f579c7450d64195212c2fe93ff991b38b804ac874d824fecb5b7e4bc8
run #0: basic kernel testing failed: WARNING in __nf_unregister_net_hook
run #1: basic kernel testing failed: WARNING in __nf_unregister_net_hook
run #2: basic kernel testing failed: WARNING in __nf_unregister_net_hook
run #3: basic kernel testing failed: WARNING in __nf_unregister_net_hook
run #4: basic kernel testing failed: WARNING in __nf_unregister_net_hook
run #5: basic kernel testing failed: WARNING in __nf_unregister_net_hook
run #6: crashed: WARNING in __nf_unregister_net_hook
run #7: basic kernel testing failed: WARNING in __nf_unregister_net_hook
run #8: basic kernel testing failed: WARNING in __nf_unregister_net_hook
run #9: crashed: WARNING in __nf_unregister_net_hook
revisions tested: 2, total time: 21m28.137359729s (build: 11m39.578606164s, test: 8m54.833369812s)
the crash still happens on HEAD
commit msg: Merge tag 'tag-chrome-platform-for-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux
crash: WARNING in __nf_unregister_net_hook
------------[ cut here ]------------
hook not found, pf 3 num 0
WARNING: CPU: 1 PID: 238 at net/netfilter/core.c:480 __nf_unregister_net_hook+0x187/0x580 net/netfilter/core.c:480
Modules linked in:
CPU: 1 PID: 238 Comm: kworker/u4:4 Not tainted 5.12.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
RIP: 0010:__nf_unregister_net_hook+0x187/0x580 net/netfilter/core.c:480
Code: 89 f0 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 d6 03 00 00 8b 53 1c 44 89 e6 48 c7 c7 40 38 c1 89 4c 89 04 24 e8 b1 2c 61 01 <0f> 0b 4c 8b 04 24 e9 ba 00 00 00 48 89 ea 48 c1 e2 04 49 8d 7c 10
RSP: 0018:ffffc9000153fbf0 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff8880221a0c00 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000004 RDI: fffff520002a7f70
RBP: 0000000000000000 R08: 0000000000000001 R09: ffff8880b9f1fa5b
R10: ffffed10173e3f4b R11: 0000000000000001 R12: 0000000000000003
R13: ffff8880186a8000 R14: ffff8880221a0c1c R15: ffff8880186a8f20
FS:  0000000000000000(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2034e0a000 CR3: 0000000011987000 CR4: 0000000000350ee0
Call Trace:
 nf_unregister_net_hook net/netfilter/core.c:502 [inline]
 nf_unregister_net_hooks+0xb1/0xf0 net/netfilter/core.c:576
 ops_pre_exit_list net/core/net_namespace.c:165 [inline]
 cleanup_net+0x3a4/0x990 net/core/net_namespace.c:583
 process_one_work+0x84c/0x13d0 kernel/workqueue.c:2275
 worker_thread+0x598/0xf80 kernel/workqueue.c:2421
 kthread+0x36f/0x450 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294