gfs2: path_lookup on /dev/nbd returned error -2
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BUG: unable to handle kernel paging request at ffffc90000003e88
PGD 1da95a067 P4D 1da95a067 PUD 1da95b067 PMD 1da95d067 PTE 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 20832 Comm: syz-executor2 Not tainted 4.20.0-rc7+ #381
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:_find_next_bit lib/find_bit.c:43 [inline]
RIP: 0010:find_next_zero_bit+0x5a/0x140 lib/find_bit.c:83
Code: dc 95 ee fd 48 89 d8 48 c1 e8 06 4d 8d 24 c6 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 80 3c 02 00 0f 85 cf 00 00 00 <4d> 8b 24 24 89 d9 31 ff 48 83 e3 c0 4c 89 e0 49 c7 c4 ff ff ff ff
RSP: 0018:ffff88818e407010 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: 000000000001f44e RCX: ffffc90009e26000
RDX: 1ffff920000007d1 RSI: ffffffff8390ee94 RDI: 0000000000000006
RBP: ffff88818e407038 R08: ffff8881d25d8200 R09: 0000000000000000
R10: ffffed1031c80e0b R11: 0000000000000003 R12: ffffc90000003e88
R13: 000000000001f858 R14: ffffc90000000000 R15: ffffc90000000000
FS:  00007f66e15b1700(0000) GS:ffff8881dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc90000003e88 CR3: 00000001b9d50000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 bitmap_find_next_zero_area_off+0x84/0xd0 lib/bitmap.c:314
 bitmap_find_next_zero_area include/linux/bitmap.h:171 [inline]
 pcpu_alloc_area+0x1ab/0x4a0 mm/percpu.c:992
 pcpu_alloc+0x8b0/0x15e0 mm/percpu.c:1428
 __alloc_percpu_gfp+0x27/0x30 mm/percpu.c:1546
 dst_cache_init+0x2b/0xd0 net/core/dst_cache.c:146
 ip_tunnel_init+0x155/0x450 net/ipv4/ip_tunnel.c:1189
 erspan_tunnel_init+0x215/0x280 net/ipv4/ip_gre.c:1317
 register_netdevice+0x332/0x11d0 net/core/dev.c:8471
 __ip_tunnel_create+0x361/0x550 net/ipv4/ip_tunnel.c:282
 ip_tunnel_init_net+0x3fc/0xac0 net/ipv4/ip_tunnel.c:1029
 erspan_init_net+0x29/0x30 net/ipv4/ip_gre.c:1656
 ops_init+0x101/0x560 net/core/net_namespace.c:129
 setup_net+0x362/0x8d0 net/core/net_namespace.c:314
kobject: 'loop1' (000000004c0d9fb2): kobject_uevent_env
kobject: 'loop1' (000000004c0d9fb2): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop4' (00000000c14b0004): kobject_uevent_env
 copy_net_ns+0x2b1/0x4a0 net/core/net_namespace.c:437
kobject: 'loop4' (00000000c14b0004): fill_kobj_path: path = '/devices/virtual/block/loop4'
 create_new_namespaces+0x6ad/0x900 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xc3/0x1f0 kernel/nsproxy.c:206
 ksys_unshare+0x79c/0x10b0 kernel/fork.c:2539
 __do_sys_unshare kernel/fork.c:2607 [inline]
 __se_sys_unshare kernel/fork.c:2605 [inline]
 __x64_sys_unshare+0x31/0x40 kernel/fork.c:2605
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
Trying to vfree() nonexistent vm area (00000000735b2a29)
WARNING: CPU: 1 PID: 20848 at mm/vmalloc.c:1511 __vunmap+0x397/0x460 mm/vmalloc.c:1510