Hi All,
Since kernel 5.15 (IIRC) I've been getting a suspicous RCU usage warning
from the iwlwifi driver when running a kernel with checks for this enabled.
Note this is the 2nd or 3th time this happens now, can we please get
some CI checks for these (assuming there is some iwlwifi CI already) ?
Here is the warning which I'm getting:
[ 71.769680] iwlwifi 0000:00:14.3: base HW address: 34:13:e8:dd:0f:63
[ 71.769708] =============================
[ 71.769710] WARNING: suspicious RCU usage
[ 71.769711] 5.16.0-rc2+ #632 Tainted: G E
[ 71.769713] -----------------------------
[ 71.769715] drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c:264 suspicious rcu_dereference_protected() usage!
[ 71.769717]
other info that might help us debug this:
[ 71.769719]
rcu_scheduler_active = 2, debug_locks = 1
[ 71.769721] 3 locks held by modprobe/1712:
[ 71.769723] #0: ffffffffc0d6e0e8 (iwlwifi_opmode_table_mtx){+.+.}-{3:3}, at: iwl_opmode_register+0x2c/0xe0 [iwlwifi]
[ 71.769744] #1: ffffffffa9bc2248 (rtnl_mutex){+.+.}-{3:3}, at: iwl_op_mode_mvm_start+0x9e7/0xc90 [iwlmvm]
[ 71.769771] #2: ffff8a9d0884b3a0 (&mvm->mutex){+.+.}-{3:3}, at: iwl_op_mode_mvm_start+0x9f3/0xc90 [iwlmvm]
[ 71.769789]
stack backtrace:
[ 71.769791] CPU: 3 PID: 1712 Comm: modprobe Tainted: G E 5.16.0-rc2+ #632
[ 71.769794] Hardware name: LENOVO 20U90SIT19/20U90SIT19, BIOS N2WET30W (1.20 ) 08/26/2021
[ 71.769795] Call Trace:
[ 71.769797] <TASK>
[ 71.769799] dump_stack_lvl+0x59/0x73
[ 71.769805] iwl_mvm_init_fw_regd+0x110/0x170 [iwlmvm]
[ 71.769822] iwl_mvm_init_mcc+0x42/0x1b0 [iwlmvm]
[ 71.769837] iwl_op_mode_mvm_start+0xc32/0xc90 [iwlmvm]
[ 71.769859] _iwl_op_mode_start.isra.0+0x3f/0x80 [iwlwifi]
[ 71.769871] iwl_opmode_register+0x6f/0xe0 [iwlwifi]
[ 71.769881] ? 0xffffffffc0ef1000
[ 71.769885] iwl_mvm_init+0x36/0x1000 [iwlmvm]
[ 71.769900] do_one_initcall+0x58/0x300
[ 71.769904] ? rcu_read_lock_sched_held+0x3f/0x70
[ 71.769908] ? trace_kmalloc+0x2c/0xd0
[ 71.769912] ? kmem_cache_alloc_trace+0x1e8/0x3a0
[ 71.769919] do_init_module+0x5c/0x260
[ 71.769925] __do_sys_init_module+0x130/0x190
[ 71.769942] do_syscall_64+0x38/0x90
[ 71.769947] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 71.769950] RIP: 0033:0x7fa9255f599e
[ 71.769954] Code: 48 8b 0d 8d 74 0e 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 af 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 5a 74 0e 00 f7 d8 64 89 01 48
[ 71.769956] RSP: 002b:00007ffd859069e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000af
[ 71.769960] RAX: ffffffffffffffda RBX: 000055796d7dbe40 RCX: 00007fa9255f599e
[ 71.769962] RDX: 000055796d167a2a RSI: 00000000000fcf09 RDI: 000055796e264bf0
[ 71.769963] RBP: 000055796e264bf0 R08: 000055796d7dbd90 R09: 00000000000fc010
[ 71.769965] R10: 0000000000000005 R11: 0000000000000246 R12: 000055796d167a2a
[ 71.769967] R13: 000055796d7dbf70 R14: 000055796d7dbe40 R15: 000055796d7df170
[ 71.769982] </TASK>
[ 71.773112] ------------[ cut here ]------------
[ 71.773115] WARNING: CPU: 5 PID: 1712 at net/wireless/reg.c:3107 reg_process_self_managed_hint+0x198/0x1e0 [cfg80211]
[ 71.773157] Modules linked in: intel_uncore(+) snd_compress ac97_bus snd_pcm_dmaengine snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi cdc_ether usbnet snd_hda_codec iwlmvm(+) snd_usb_audio(+) pcspkr r8152 snd_hda_core snd_usbmidi_lib snd_rawmidi snd_hwdep mii mac80211 snd_seq uvcvideo snd_seq_device think_lmi(E+) videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 firmware_attributes_class(E) wmi_bmof(E) i2c_i801(E) snd_pcm e1000e(+) intel_wmi_thunderbolt(E) libarc4 btusb videobuf2_common btrtl i2c_smbus snd_timer btbcm videodev btintel bluetooth mc iwlwifi mei_me ecdh_generic thunderbolt(+) processor_thermal_device_pci_legacy mei processor_thermal_device cfg80211 joydev processor_thermal_rfim processor_thermal_mbox processor_thermal_rapl nxp_nci_i2c idma64 intel_rapl_common nxp_nci intel_pch_thermal nci intel_soc_dts_iosf nfc thinkpad_acpi(E) ledtrig_audio platform_profile rfkill snd soundcore int3403_thermal int340x_thermal_zone soc_button_array acpi_pad int3400_thermal
[ 71.773280] acpi_thermal_rel intel_hid(E) sparse_keymap binfmt_misc zram ip_tables dm_crypt trusted asn1_encoder hid_logitech_hidpp hid_logitech_dj hid_lg_g15 uas usb_storage crct10dif_pclmul crc32_pclmul crc32c_intel i915 ghash_clmulni_intel serio_raw i2c_algo_bit ttm nvme drm_kms_helper nvme_core cec hid_multitouch ucsi_acpi drm typec_ucsi typec wmi i2c_hid_acpi i2c_hid video pinctrl_cannonlake i2c_dev ipmi_devintf ipmi_msghandler fuse
[ 71.773346] CPU: 5 PID: 1712 Comm: modprobe Tainted: G E 5.16.0-rc2+ #632
[ 71.773349] Hardware name: LENOVO 20U90SIT19/20U90SIT19, BIOS N2WET30W (1.20 ) 08/26/2021
[ 71.773351] RIP: 0010:reg_process_self_managed_hint+0x198/0x1e0 [cfg80211]
[ 71.773384] Code: 0e f1 02 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 49 8d 7c 24 68 be ff ff ff ff e8 f0 3f 22 e8 85 c0 0f 85 b8 fe ff ff <0f> 0b e9 b1 fe ff ff 0f 0b 80 3d 9f 7d 0b 00 00 0f 85 94 fe ff ff
[ 71.773387] RSP: 0018:ffff9c284154bc50 EFLAGS: 00010246
[ 71.773392] RAX: 0000000000000000 RBX: ffff8a9d0884b308 RCX: 0000000000000001
[ 71.773394] RDX: 0000000000000000 RSI: ffff8a9d08848628 RDI: ffff8a9d07cd8ea0
[ 71.773398] RBP: ffff9c284154bcc8 R08: 0000000000000000 R09: 0000000000000001
[ 71.773400] R10: ffffffffaac17c80 R11: 000000000000e000 R12: ffff8a9d088485c0
[ 71.773402] R13: ffff8a9d0884b308 R14: ffff9c284154bd30 R15: ffff8a9d0884b300
[ 71.773405] FS: 00007fa9254de740(0000) GS:ffff8aa05a540000(0000) knlGS:0000000000000000
[ 71.773408] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 71.773411] CR2: 000055fd1b31c350 CR3: 00000001078d2002 CR4: 00000000003706e0
[ 71.773413] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 71.773416] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 71.773418] Call Trace:
[ 71.773420] <TASK>
[ 71.773422] ? rcu_read_lock_sched_held+0x3f/0x70
[ 71.773440] regulatory_set_wiphy_regd_sync+0x31/0x90 [cfg80211]
[ 71.773485] iwl_mvm_init_mcc+0xa9/0x1b0 [iwlmvm]
[ 71.773510] iwl_op_mode_mvm_start+0xc32/0xc90 [iwlmvm]
[ 71.773538] _iwl_op_mode_start.isra.0+0x3f/0x80 [iwlwifi]
[ 71.773554] iwl_opmode_register+0x6f/0xe0 [iwlwifi]
[ 71.773566] ? 0xffffffffc0ef1000
[ 71.773571] iwl_mvm_init+0x36/0x1000 [iwlmvm]
[ 71.773589] do_one_initcall+0x58/0x300
[ 71.773595] ? rcu_read_lock_sched_held+0x3f/0x70
[ 71.773599] ? trace_kmalloc+0x2c/0xd0
[ 71.773603] ? kmem_cache_alloc_trace+0x1e8/0x3a0
[ 71.773613] do_init_module+0x5c/0x260
[ 71.773620] __do_sys_init_module+0x130/0x190
[ 71.773641] do_syscall_64+0x38/0x90
[ 71.773646] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 71.773651] RIP: 0033:0x7fa9255f599e
[ 71.773654] Code: 48 8b 0d 8d 74 0e 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 af 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 5a 74 0e 00 f7 d8 64 89 01 48
[ 71.773657] RSP: 002b:00007ffd859069e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000af
[ 71.773674] RAX: ffffffffffffffda RBX: 000055796d7dbe40 RCX: 00007fa9255f599e
[ 71.773677] RDX: 000055796d167a2a RSI: 00000000000fcf09 RDI: 000055796e264bf0
[ 71.773679] RBP: 000055796e264bf0 R08: 000055796d7dbd90 R09: 00000000000fc010
[ 71.773681] R10: 0000000000000005 R11: 0000000000000246 R12: 000055796d167a2a
[ 71.773683] R13: 000055796d7dbf70 R14: 000055796d7dbe40 R15: 000055796d7df170
[ 71.773699] </TASK>
[ 71.773700] irq event stamp: 166083
[ 71.773702] hardirqs last enabled at (166089): [<ffffffffa816e5d0>] __up_console_sem+0x60/0x70
[ 71.773705] hardirqs last disabled at (166094): [<ffffffffa816e5b5>] __up_console_sem+0x45/0x70
[ 71.773708] softirqs last enabled at (165934): [<ffffffffa80ec5f0>] __irq_exit_rcu+0xd0/0x100
[ 71.773711] softirqs last disabled at (165929): [<ffffffffa80ec5f0>] __irq_exit_rcu+0xd0/0x100
[ 71.773714] ---[ end trace ba8c4bf440db1ae1 ]---
Regards,
Hans
