Hello
Since linux-next-20170516 I got the following warning trace:
[ 4.310450] nf_tables: (c) 2007-2009 Patrick McHardy <ka...@trash.net>
[ 4.321211] ============================================
[ 4.326516] WARNING: possible recursive locking detected
[ 4.331823] 4.12.0-rc1-next-20170518+ #274 Not tainted
[ 4.336954] --------------------------------------------
[ 4.342258] swapper/0/1 is trying to acquire lock:
[ 4.347043] (cpu_hotplug_lock.rw_sem){++++++}, at: [<c01ccb28>]
stop_machine+0x1c/0x3c
[ 4.355060]
but task is already holding lock:
[ 4.360886] (cpu_hotplug_lock.rw_sem){++++++}, at: [<c01f46c4>]
static_key_slow_inc+0x14/0x24
[ 4.369501]
other info that might help us debug this:
[ 4.376021] Possible unsafe locking scenario:
[ 4.381933] CPU0
[ 4.384368] ----
[ 4.386812] lock(cpu_hotplug_lock.rw_sem);
[ 4.391082] lock(cpu_hotplug_lock.rw_sem);
[ 4.395352]
*** DEADLOCK ***
[ 4.401265] May be due to missing lock nesting notation
[ 4.408046] 5 locks held by swapper/0/1:
[ 4.411962] #0: (net_mutex){+.+.+.}, at: [<c05d4c08>]
register_pernet_subsys+0x28/0x48
[ 4.420063] #1: (register_ipv4_hooks){+.+.+.}, at: [<c06a4954>]
ipv4_hooks_register+0xdc/0x1e0
[ 4.428856] #2: (defrag4_mutex){+.+.+.}, at: [<c06a5648>]
nf_defrag_ipv4_enable+0x48/0x8c
[ 4.437213] #3: (cpu_hotplug_lock.rw_sem){++++++}, at: [<c01f46c4>]
static_key_slow_inc+0x14/0x24
[ 4.446261] #4: (jump_label_mutex){+.+...}, at: [<c01f463c>]
__static_key_slow_inc+0x78/0xec
[ 4.454877]
stack backtrace:
[ 4.459234] CPU: 0 PID: 1 Comm: swapper/0 Not tainted
4.12.0-rc1-next-20170518+ #274
[ 4.466965] Hardware name: Allwinner sun8i Family
[ 4.471664] Backtrace:
[ 4.474121] [<c010c6d8>] (dump_backtrace) from [<c010c9b0>]
(show_stack+0x18/0x1c)
[ 4.481684] r7:c0c2dbd0 r6:00000000 r5:60000093 r4:c0c2dbd0
[ 4.487343] [<c010c998>] (show_stack) from [<c03e86fc>]
(dump_stack+0xac/0xd8)
[ 4.494564] [<c03e8650>] (dump_stack) from [<c017640c>]
(__lock_acquire+0xbc0/0x19f0)
[ 4.502389] r10:ef05b200 r9:c0d8775c r8:00000000 r7:c0c2dcc0 r6:00000000
r5:c14804c0
[ 4.510210] r4:c0d8775c r3:00000000
[ 4.513788] [<c017584c>] (__lock_acquire) from [<c0177a00>]
(lock_acquire+0x74/0x90)
[ 4.521526] r10:c0b37858 r9:c0c55348 r8:00000001 r7:00000001 r6:60000013
r5:00000000
[ 4.529344] r4:ffffe000
[ 4.531883] [<c017798c>] (lock_acquire) from [<c0125500>]
(get_online_cpus+0x58/0xe0)
[ 4.539706] r8:c0959750 r7:c01ccb28 r6:c0c18ff4 r5:00000000 r4:c0c19644
[ 4.546404] [<c01254a8>] (get_online_cpus) from [<c01ccb28>]
(stop_machine+0x1c/0x3c)
[ 4.554226] r7:c09bd960 r6:00000000 r5:ef04dce8 r4:c010f964
[ 4.559885] [<c01ccb0c>] (stop_machine) from [<c010f9b0>]
(patch_text+0x2c/0x34)
[ 4.567273] r7:c09bd960 r6:c14989d4 r5:c0c58b64 r4:c06ae18c
[ 4.572932] [<c010f984>] (patch_text) from [<c010f79c>]
(arch_jump_label_transform+0x28/0x44)
[ 4.581450] [<c010f774>] (arch_jump_label_transform) from [<c01f3bf8>]
(__jump_label_update+0x94/0x9c)
[ 4.590745] r5:c0c58b64 r4:c0c58a68
[ 4.594322] [<c01f3b64>] (__jump_label_update) from [<c01f42ec>]
(jump_label_update+0x94/0x130)
[ 4.603011] r7:c09bd960 r6:eea28f80 r5:c14989d4 r4:c0c58b64
[ 4.608668] [<c01f4258>] (jump_label_update) from [<c01f469c>]
(__static_key_slow_inc+0xd8/0xec)
[ 4.617444] r7:c09bd960 r6:eea28f80 r5:c0c57964 r4:c14989d4
[ 4.623101] [<c01f45c4>] (__static_key_slow_inc) from [<c01f46cc>]
(static_key_slow_inc+0x1c/0x24)
[ 4.632047] r5:c0c57964 r4:c14989d4
[ 4.635628] [<c01f46b0>] (static_key_slow_inc) from [<c061763c>]
(nf_register_net_hook+0x148/0x1a8)
[ 4.644662] r5:c0c57964 r4:c0c501c0
[ 4.648242] [<c06174f4>] (nf_register_net_hook) from [<c0617f90>]
(nf_register_net_hooks+0x40/0x78)
[ 4.657279] r9:c0c55348 r8:00000002 r7:c0c4fd00 r6:c0c57b15 r5:00000000
r4:c0c55348
[ 4.665019] [<c0617f50>] (nf_register_net_hooks) from [<c06a5674>]
(nf_defrag_ipv4_enable+0x74/0x8c)
[ 4.674143] r9:c0c578ae r8:00000009 r7:00000009 r6:c0c57b15 r5:c0c4fd00
r4:00000000
[ 4.681883] [<c06a5600>] (nf_defrag_ipv4_enable) from [<c06a4a1c>]
(ipv4_hooks_register+0x1a4/0x1e0)
[ 4.691003] r5:c0c4fd00 r4:eea280c0
[ 4.694584] [<c06a4878>] (ipv4_hooks_register) from [<c06241c8>]
(nf_ct_l3proto_pernet_register+0x30/0x3c)
[ 4.704226] r7:ef0dc980 r6:c0c4fd00 r5:c0c4fd00 r4:00000000
[ 4.709886] [<c0624198>] (nf_ct_l3proto_pernet_register) from [<c06a4ea8>]
(ipv4_net_init+0x30/0x68)
[ 4.719012] [<c06a4e78>] (ipv4_net_init) from [<c05d420c>]
(ops_init+0x104/0x16c)
[ 4.726486] r5:eea280c0 r4:c0c552a0
[ 4.730065] [<c05d4108>] (ops_init) from [<c05d4b3c>]
(register_pernet_operations+0x108/0x1ac)
[ 4.738670] r9:c0c43cbc r8:ef04de70 r7:c0c4fcd0 r6:c0c552a0 r5:00000000
r4:c0c4fd00
[ 4.746409] [<c05d4a34>] (register_pernet_operations) from [<c05d4c14>]
(register_pernet_subsys+0x34/0x48)
[ 4.756054] r9:00000000 r8:c0c60780 r7:c0b37850 r6:c0c552a0 r5:c0c4fc44
r4:c0c4fc40
[ 4.763797] [<c05d4be0>] (register_pernet_subsys) from [<c0b2cf5c>]
(nf_conntrack_l3proto_ipv4_init+0x38/0xb4)
[ 4.773786] r7:c0b37850 r6:ffffe000 r5:c0b2cf24 r4:00000000
[ 4.779447] [<c0b2cf24>] (nf_conntrack_l3proto_ipv4_init) from [<c0101954>]
(do_one_initcall+0x5c/0x198)
[ 4.788913] r5:c0b2cf24 r4:c0c0f4cc
[ 4.792494] [<c01018f8>] (do_one_initcall) from [<c0b00ff0>]
(kernel_init_freeable+0x254/0x2e8)
[ 4.801185] r9:00000007 r8:c0c60780 r7:c0b37850 r6:c0c60780 r5:c0b48060
r4:c09ff22c
[ 4.808926] [<c0b00d9c>] (kernel_init_freeable) from [<c070caf0>]
(kernel_init+0x10/0x118)
[ 4.817184] r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000
r5:c070cae0
[ 4.825001] r4:00000000
[ 4.827542] [<c070cae0>] (kernel_init) from [<c0107f70>]
(ret_from_fork+0x14/0x24)
[ 4.835102] r5:c070cae0 r4:00000000
But the same kernel config without netfilter got:
[ 11.748845] ============================================
[ 11.754151] WARNING: possible recursive locking detected
[ 11.759460] 4.12.0-rc1-next-20170518+ #278 Not tainted
[ 11.764591] --------------------------------------------
[ 11.769897] mount/459 is trying to acquire lock:
[ 11.774510] (cpu_hotplug_lock.rw_sem){++++++}, at: [<c01ccb28>]
stop_machine+0x1c/0x3c
[ 11.782527]
but task is already holding lock:
[ 11.788352] (cpu_hotplug_lock.rw_sem){++++++}, at: [<c01f445c>]
static_key_slow_dec+0x28/0x64
[ 11.796968]
other info that might help us debug this:
[ 11.803488] Possible unsafe locking scenario:
[ 11.809400] CPU0
[ 11.811844] ----
[ 11.814287] lock(cpu_hotplug_lock.rw_sem);
[ 11.818557] lock(cpu_hotplug_lock.rw_sem);
[ 11.822827]
*** DEADLOCK ***
[ 11.828741] May be due to missing lock nesting notation
[ 11.835522] 3 locks held by mount/459:
[ 11.839266] #0: (cgroup_mutex){+.+.+.}, at: [<c01bdf30>]
cgroup_lock_and_drain_offline+0x38/0x318
[ 11.848318] #1: (cpu_hotplug_lock.rw_sem){++++++}, at: [<c01f445c>]
static_key_slow_dec+0x28/0x64
[ 11.857367] #2: (jump_label_mutex){+.+...}, at: [<c01f43a8>]
__static_key_slow_dec+0x20/0xac
[ 11.865983]
stack backtrace:
[ 11.870341] CPU: 3 PID: 459 Comm: mount Not tainted
4.12.0-rc1-next-20170518+ #278
[ 11.877899] Hardware name: Allwinner sun8i Family
[ 11.882596] Backtrace:
[ 11.885054] [<c010c6d8>] (dump_backtrace) from [<c010c9b0>]
(show_stack+0x18/0x1c)
[ 11.892618] r7:c0a24f50 r6:00000000 r5:600f0093 r4:c0a24f50
[ 11.898277] [<c010c998>] (show_stack) from [<c03e86fc>]
(dump_stack+0xac/0xd8)
[ 11.905499] [<c03e8650>] (dump_stack) from [<c017640c>]
(__lock_acquire+0xbc0/0x19f0)
[ 11.913324] r10:eebe4b00 r9:c0b7d61c r8:00000000 r7:c0a25040 r6:00000000
r5:c1276380
[ 11.921143] r4:c0b7d61c r3:00000000
[ 11.924721] [<c017584c>] (__lock_acquire) from [<c0177a00>]
(lock_acquire+0x74/0x90)
[ 11.932458] r10:c1266c28 r9:c1266c28 r8:00000001 r7:00000001 r6:600f0013
r5:00000000
[ 11.940277] r4:ffffe000
[ 11.942817] [<c017798c>] (lock_acquire) from [<c0125500>]
(get_online_cpus+0x58/0xe0)
[ 11.950640] r8:0000003c r7:c01ccb28 r6:c0a10374 r5:00000000 r4:c0a109c4
[ 11.957337] [<c01254a8>] (get_online_cpus) from [<c01ccb28>]
(stop_machine+0x1c/0x3c)
[ 11.965160] r7:c12658c4 r6:00000000 r5:eeb85ca0 r4:c010f964
[ 11.970819] [<c01ccb0c>] (stop_machine) from [<c010f9b0>]
(patch_text+0x2c/0x34)
[ 11.978208] r7:c12658c4 r6:c0a16b14 r5:c0a4eff8 r4:c01c6f38
[ 11.983867] [<c010f984>] (patch_text) from [<c010f79c>]
(arch_jump_label_transform+0x28/0x44)
[ 11.992387] [<c010f774>] (arch_jump_label_transform) from [<c01f3bf8>]
(__jump_label_update+0x94/0x9c)
[ 12.001681] r5:c0a4eff8 r4:c0a4ebf0
[ 12.005259] [<c01f3b64>] (__jump_label_update) from [<c01f42ec>]
(jump_label_update+0x94/0x130)
[ 12.013948] r7:c12658c4 r6:00000000 r5:c0a16b14 r4:c0a4eff8
[ 12.019606] [<c01f4258>] (jump_label_update) from [<c01f43ec>]
(__static_key_slow_dec+0x64/0xac)
[ 12.028382] r7:c12658c4 r6:00000000 r5:00000000 r4:c0a16b14
[ 12.034040] [<c01f4388>] (__static_key_slow_dec) from [<c01f446c>]
(static_key_slow_dec+0x38/0x64)
[ 12.042990] r7:c12658c4 r6:c0a17458 r5:eeaa6000 r4:c0a16b14
[ 12.048647] [<c01f4434>] (static_key_slow_dec) from [<c01f44cc>]
(static_key_disable+0x34/0x68)
[ 12.057335] r5:eeaa6000 r4:c0a16b14
[ 12.060913] [<c01f4498>] (static_key_disable) from [<c01bdb54>]
(rebind_subsystems+0x320/0x3fc)
[ 12.069601] r5:eeaa6000 r4:eeaa6010
[ 12.073179] [<c01bd834>] (rebind_subsystems) from [<c01bdd84>]
(cgroup_setup_root+0x154/0x2c8)
[ 12.081784] r10:c0a164e0 r9:eeaa6018 r8:c0a16a94 r7:00000000 r6:eeaa6000
r5:eeb85dd0
[ 12.089603] r4:eeaa6010
[ 12.092140] [<c01bdc30>] (cgroup_setup_root) from [<c01c2f54>]
(cgroup1_mount+0x62c/0x848)
[ 12.100398] r10:c0a1661c r9:00000001 r8:c0a16aac r7:00000000 r6:c12657f0
r5:eeaa6000
[ 12.108216] r4:c0a16904
[ 12.110755] [<c01c2928>] (cgroup1_mount) from [<c01bc4bc>]
(cgroup_mount+0xc8/0x430)
[ 12.118492] r10:00000000 r9:ef238000 r8:c0a16a30 r7:c0a169b0 r6:c0a16a30
r5:eea7a880
[ 12.126311] r4:c0a07584
[ 12.128851] [<c01bc3f4>] (cgroup_mount) from [<c024e6a0>]
(mount_fs+0x1c/0xac)
[ 12.136069] r10:00000000 r9:ef238000 r8:c0a16a30 r7:c0273b70 r6:c0a16a30
r5:eea7a880
[ 12.143887] r4:c01bc3f4
[ 12.146427] [<c024e684>] (mount_fs) from [<c026ff04>]
(vfs_kern_mount+0x5c/0x130)
[ 12.153903] r6:00000000 r5:eea7a880 r4:eea42700
[ 12.158522] [<c026fea8>] (vfs_kern_mount) from [<c0273b70>]
(do_mount+0x164/0xc98)
[ 12.166086] r9:eea7a2c0 r8:c0274a50 r7:eea7a880 r6:00000027 r5:ef238000
r4:c0a16a30
[ 12.173822] [<c0273a0c>] (do_mount) from [<c0274a50>] (SyS_mount+0x94/0xbc)
[ 12.180781] r10:00000000 r9:eeb84000 r8:c0ed000e r7:010ec1b0 r6:ef238000
r5:eea7a2c0
[ 12.188599] r4:eea7a880
[ 12.191139] [<c02749bc>] (SyS_mount) from [<c0107ee0>]
(ret_fast_syscall+0x0/0x1c)
[ 12.198703] r8:c0108084 r7:00000015 r6:010ec1a0 r5:00000000 r4:010ec170
Regards
