While booting linux mainline kernel on arm64 db410c this kernel warning noticed. metadata: git branch: master git repo: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git commit: f75aef392f869018f78cfedf3c320a6b3fcfda6b git describe: v5.9-rc3 make_kernelversion: 5.9.0-rc3 kernel-config: http://snapshots.linaro.org/openembedded/lkft/lkft/sumo/dragonboard-410c/lkft/linux-mainline/2965/config Boot log, [ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd030] [ 0.000000] Linux version 5.9.0-rc3 (oe-user@oe-host) (aarch64-linaro-linux-gcc (GCC) 7.3.0, GNU ld (GNU Binutils) 2.30.0.20180208) #1 SMP PREEMPT Mon Aug 31 00:23:15 UTC 2020 [ 0.000000] Machine model: Qualcomm Technologies, Inc. APQ 8016 SBC <> [ 5.299090] sdhci: Secure Digital Host Controller Interface driver [ 5.299140] sdhci: Copyright(c) Pierre Ossman [ 5.304313] [ 5.307771] Synopsys Designware Multimedia Card Interface Driver [ 5.308588] ============================= [ 5.308593] WARNING: suspicious RCU usage [ 5.316628] sdhci-pltfm: SDHCI platform and OF driver helper [ 5.320052] 5.9.0-rc3 #1 Not tainted [ 5.320057] ----------------------------- [ 5.320063] /usr/src/kernel/include/trace/events/lock.h:37 suspicious rcu_dereference_check() usage! [ 5.320068] [ 5.320068] other info that might help us debug this: [ 5.320068] [ 5.320074] [ 5.320074] rcu_scheduler_active = 2, debug_locks = 1 [ 5.320078] RCU used illegally from extended quiescent state! [ 5.320084] no locks held by swapper/0/0. [ 5.320089] [ 5.320089] stack backtrace: [ 5.320098] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.9.0-rc3 #1 [ 5.346354] sdhci_msm 7864900.sdhci: Got CD GPIO [ 5.346446] Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT) [ 5.346452] Call trace: [ 5.346463] dump_backtrace+0x0/0x1f8 [ 5.346471] show_stack+0x2c/0x38 [ 5.346480] dump_stack+0xec/0x15c [ 5.346490] lockdep_rcu_suspicious+0xd4/0xf8 [ 5.346499] lock_acquire+0x3d0/0x440 [ 5.346510] _raw_spin_lock_irqsave+0x80/0xb0 [ 5.413118] __pm_runtime_suspend+0x34/0x1d0 [ 5.417457] psci_enter_domain_idle_state+0x4c/0xb0 [ 5.421795] cpuidle_enter_state+0xc8/0x610 [ 5.426392] cpuidle_enter+0x3c/0x50 [ 5.430561] call_cpuidle+0x44/0x80 [ 5.434378] do_idle+0x240/0x2a0 [ 5.437589] cpu_startup_entry+0x2c/0x78 [ 5.441063] rest_init+0x1ac/0x280 [ 5.444970] arch_call_rest_init+0x14/0x1c [ 5.448180] start_kernel+0x50c/0x544 [ 5.452395] [ 5.452399] [ 5.452403] ============================= [ 5.452406] WARNING: suspicious RCU usage [ 5.452409] 5.9.0-rc3 #1 Not tainted [ 5.452412] ----------------------------- [ 5.452417] /usr/src/kernel/include/trace/events/ipi.h:36 suspicious rcu_dereference_check() usage! [ 5.452420] [ 5.452424] other info that might help us debug this: [ 5.452426] [ 5.452429] [ 5.452432] rcu_scheduler_active = 2, debug_locks = 1 [ 5.452436] RCU used illegally from extended quiescent state! [ 5.452440] 1 lock held by swapper/0/0: [ 5.452443] #0: ffff8000127408f8 (logbuf_lock){-...}-{2:2}, at: vprintk_emit+0xb0/0x358 [ 5.452458] [ 5.452461] stack backtrace: [ 5.452465] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.9.0-rc3 #1 [ 5.452469] Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT) [ 5.452472] Call trace: [ 5.452476] dump_backtrace+0x0/0x1f8 [ 5.452479] show_stack+0x2c/0x38 [ 5.452481] dump_stack+0xec/0x15c [ 5.452485] lockdep_rcu_suspicious+0xd4/0xf8 [ 5.452489] arch_irq_work_raise+0x208/0x210 [ 5.452493] __irq_work_queue_local+0x64/0x88 [ 5.452495] irq_work_queue+0x3c/0x88 [ 5.452499] printk_safe_log_store+0x148/0x178 [ 5.452502] vprintk_func+0x1cc/0x2b8 [ 5.452506] printk+0x74/0x94 [ 5.452509] lockdep_rcu_suspicious+0x28/0xf8 [ 5.452512] lock_release+0x338/0x360 [ 5.452516] _raw_spin_unlock+0x3c/0xa0 [ 5.452519] vprintk_emit+0xf8/0x358 [ 5.452522] vprintk_default+0x48/0x58 [ 5.452526] vprintk_func+0xec/0x2b8 [ 5.452528] printk+0x74/0x94 [ 5.452532] lockdep_rcu_suspicious+0x28/0xf8 [ 5.452535] lock_acquire+0x3d0/0x440 [ 5.452538] _raw_spin_lock_irqsave+0x80/0xb0 [ 5.452542] __pm_runtime_suspend+0x34/0x1d0 [ 5.452545] psci_enter_domain_idle_state+0x4c/0xb0 [ 5.452549] cpuidle_enter_state+0xc8/0x610 [ 5.452552] cpuidle_enter+0x3c/0x50 [ 5.452555] call_cpuidle+0x44/0x80 [ 5.452559] do_idle+0x240/0x2a0 [ 5.452562] cpu_startup_entry+0x2c/0x78 [ 5.452564] rest_init+0x1ac/0x280 [ 5.452568] arch_call_rest_init+0x14/0x1c [ 5.452571] start_kernel+0x50c/0x544 [ 5.452575] ============================= [ 5.452578] WARNING: suspicious RCU usage [ 5.452582] 5.9.0-rc3 #1 Not tainted [ 5.452585] ----------------------------- [ 5.452590] /usr/src/kernel/include/trace/events/lock.h:63 suspicious rcu_dereference_check() usage! [ 5.452593] [ 5.452596] other info that might help us debug this: [ 5.452599] [ 5.452601] [ 5.452605] rcu_scheduler_active = 2, debug_locks = 1 [ 5.452609] RCU used illegally from extended quiescent state! [ 5.452612] 1 lock held by swapper/0/0: [ 5.452615] #0: ffff8000127408f8 (logbuf_lock){-...}-{2:2}, at: vprintk_emit+0xb0/0x358 [ 5.452630] [ 5.452633] stack backtrace: [ 5.452636] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.9.0-rc3 #1 [ 5.452640] Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT) [ 5.452643] Call trace: [ 5.452646] dump_backtrace+0x0/0x1f8 [ 5.452649] show_stack+0x2c/0x38 [ 5.452652] dump_stack+0xec/0x15c [ 5.452656] lockdep_rcu_suspicious+0xd4/0xf8 [ 5.452659] lock_release+0x338/0x360 [ 5.452662] _raw_spin_unlock+0x3c/0xa0 [ 5.452665] vprintk_emit+0xf8/0x358 [ 5.452669] vprintk_default+0x48/0x58 [ 5.452671] vprintk_func+0xec/0x2b8 [ 5.452674] printk+0x74/0x94 [ 5.452677] lockdep_rcu_suspicious+0x28/0xf8 [ 5.452680] lock_acquire+0x3d0/0x440 [ 5.452683] _raw_spin_lock_irqsave+0x80/0xb0 [ 5.452686] __pm_runtime_suspend+0x34/0x1d0 [ 5.452690] psci_enter_domain_idle_state+0x4c/0xb0 [ 5.452693] cpuidle_enter_state+0xc8/0x610 [ 5.452696] cpuidle_enter+0x3c/0x50 [ 5.452698] call_cpuidle+0x44/0x80 [ 5.452701] do_idle+0x240/0x2a0 [ 5.452704] cpu_startup_entry+0x2c/0x78 [ 5.452708] rest_init+0x1ac/0x280 [ 5.452711] arch_call_rest_init+0x14/0x1c [ 5.452714] start_kernel+0x50c/0x544 full test log link, https://qa-reports.linaro.org/lkft/linux-mainline-oe/build/v5.9-rc3/testrun/3137660/suite/linux-log-parser/test/check-kernel-warning-1722813/log -- Linaro LKFT https://lkft.linaro.org
