Created attachment 72311 [details] Kernel config Hi, every time I boot I got this: [ 0.000000] Linux version 3.3.0-rc2-t43-devel-smp-00172-g23783f8 (baryluk@sredniczarny) (gcc version 4.6.2 (Debian 4.6.2-12) ) #13 SMP Sun Feb 5 15:37:06 CET 2012 ... [ 11.721650] Running tests on trace events: ... [ 17.240580] Testing event cpu_idle: [ 17.241309] ------------[ cut here ]------------ [ 17.241318] WARNING: at include/linux/rcupdate.h:242 __atomic_notifier_call_chain+0xbc/0xf0() [ 17.241321] Hardware name: 2669UYD [ 17.241323] Modules linked in: usb_storage [ 17.241329] Pid: 0, comm: swapper/0 Not tainted 3.3.0-rc2-t43-devel-smp-00172-g23783f8 #13 [ 17.241332] Call Trace: [ 17.241340] [<c104a372>] warn_slowpath_common+0x72/0xa0 [ 17.241345] [<c17cb41c>] ? __atomic_notifier_call_chain+0xbc/0xf0 [ 17.241349] [<c17cb41c>] ? __atomic_notifier_call_chain+0xbc/0xf0 [ 17.241354] [<c104a3c0>] warn_slowpath_null+0x20/0x30 [ 17.241358] [<c17cb41c>] __atomic_notifier_call_chain+0xbc/0xf0 [ 17.241364] [<c136056e>] ? vgacon_scroll+0x5e/0x60 [ 17.241368] [<c17cb46f>] atomic_notifier_call_chain+0x1f/0x30 [ 17.241375] [<c13cdf23>] notify_write+0x23/0x30 [ 17.241379] [<c13cdf7f>] lf+0x4f/0x70 [ 17.241383] [<c13cefb9>] vt_console_print+0x249/0x380 [ 17.241388] [<c13ced70>] ? con_shutdown+0x40/0x40 [ 17.241392] [<c104a4fd>] __call_console_drivers+0x7d/0xa0 [ 17.241397] [<c104a6ec>] _call_console_drivers+0x4c/0x90 [ 17.241401] [<c104a94d>] call_console_drivers+0xdd/0x110 [ 17.241406] [<c104aa47>] console_unlock+0x77/0x170 [ 17.241410] [<c104accb>] vprintk+0x18b/0x490 [ 17.241417] [<c17b11a8>] printk+0x1d/0x1f [ 17.241423] [<c10af9e2>] lockdep_rcu_suspicious+0x22/0xe0 [ 17.241430] [<c150db78>] cpuidle_idle_call+0x238/0x300 [ 17.241437] [<c10158df>] cpu_idle+0x6f/0xc0 [ 17.241442] [<c1795caa>] rest_init+0x11e/0x124 [ 17.241447] [<c1795bf3>] ? rest_init+0x67/0x124 [ 17.241453] [<c1b5a76e>] start_kernel+0x325/0x32b [ 17.241458] [<c1b5a25a>] ? obsolete_checksetup+0x95/0x95 [ 17.241462] [<c1b5a11e>] ? reserve_ebda_region+0x6b/0x6d [ 17.241467] [<c1b5a0ac>] i386_start_kernel+0x9b/0xa2 [ 17.241470] ---[ end trace bb7f1ce54dd0def6 ]--- [ 17.241472] ------------[ cut here ]------------ [ 17.241476] WARNING: at include/linux/rcupdate.h:248 __atomic_notifier_call_chain+0xe0/0xf0() [ 17.241479] Hardware name: 2669UYD [ 17.241480] Modules linked in: usb_storage [ 17.241485] Pid: 0, comm: swapper/0 Tainted: G W 3.3.0-rc2-t43-devel-smp-00172-g23783f8 #13 [ 17.241488] Call Trace: [ 17.241492] [<c104a372>] warn_slowpath_common+0x72/0xa0 [ 17.241497] [<c17cb440>] ? __atomic_notifier_call_chain+0xe0/0xf0 [ 17.241501] [<c17cb440>] ? __atomic_notifier_call_chain+0xe0/0xf0 [ 17.241505] [<c104a3c0>] warn_slowpath_null+0x20/0x30 [ 17.241510] [<c17cb440>] __atomic_notifier_call_chain+0xe0/0xf0 [ 17.241514] [<c17cb387>] ? __atomic_notifier_call_chain+0x27/0xf0 [ 17.241519] [<c17cb46f>] atomic_notifier_call_chain+0x1f/0x30 [ 17.241523] [<c13cdf23>] notify_write+0x23/0x30 [ 17.241527] [<c13cdf7f>] lf+0x4f/0x70 [ 17.241531] [<c13cefb9>] vt_console_print+0x249/0x380 [ 17.241536] [<c13ced70>] ? con_shutdown+0x40/0x40 [ 17.241541] [<c104a4fd>] __call_console_drivers+0x7d/0xa0 [ 17.241545] [<c104a6ec>] _call_console_drivers+0x4c/0x90 [ 17.241550] [<c104a94d>] call_console_drivers+0xdd/0x110 [ 17.241554] [<c104aa47>] console_unlock+0x77/0x170 [ 17.241558] [<c104accb>] vprintk+0x18b/0x490 [ 17.241564] [<c17b11a8>] printk+0x1d/0x1f [ 17.241568] [<c10af9e2>] lockdep_rcu_suspicious+0x22/0xe0 [ 17.241573] [<c150db78>] cpuidle_idle_call+0x238/0x300 [ 17.241577] [<c10158df>] cpu_idle+0x6f/0xc0 [ 17.241581] [<c1795caa>] rest_init+0x11e/0x124 [ 17.241586] [<c1795bf3>] ? rest_init+0x67/0x124 [ 17.241590] [<c1b5a76e>] start_kernel+0x325/0x32b [ 17.241594] [<c1b5a25a>] ? obsolete_checksetup+0x95/0x95 [ 17.241599] [<c1b5a11e>] ? reserve_ebda_region+0x6b/0x6d [ 17.241603] [<c1b5a0ac>] i386_start_kernel+0x9b/0xa2 [ 17.241606] ---[ end trace bb7f1ce54dd0def7 ]--- [ 17.245110] =============================== [ 17.245163] [ INFO: suspicious RCU usage. ] [ 17.245216] 3.3.0-rc2-t43-devel-smp-00172-g23783f8 #13 Tainted: G W [ 17.245274] ------------------------------- [ 17.245328] include/trace/events/power.h:35 suspicious rcu_dereference_check() usage! [ 17.245416] [ 17.245416] other info that might help us debug this: [ 17.245418] [ 17.245562] [ 17.245563] rcu_scheduler_active = 1, debug_locks = 1 [ 17.245662] RCU used illegally from extended quiescent state! [ 17.245718] no locks held by swapper/0/0. [ 17.245770] [ 17.245771] stack backtrace: [ 17.245868] Pid: 0, comm: swapper/0 Tainted: G W 3.3.0-rc2-t43-devel-smp-00172-g23783f8 #13 [ 17.245958] Call Trace: [ 17.246011] [<c17b11a8>] ? printk+0x1d/0x1f [ 17.246067] [<c10afa78>] lockdep_rcu_suspicious+0xb8/0xe0 [ 17.246125] [<c150db78>] cpuidle_idle_call+0x238/0x300 [ 17.246183] [<c10158df>] cpu_idle+0x6f/0xc0 [ 17.246239] [<c1795caa>] rest_init+0x11e/0x124 [ 17.246295] [<c1795bf3>] ? rest_init+0x67/0x124 [ 17.246351] [<c1b5a76e>] start_kernel+0x325/0x32b [ 17.246408] [<c1b5a25a>] ? obsolete_checksetup+0x95/0x95 [ 17.246466] [<c1b5a11e>] ? reserve_ebda_region+0x6b/0x6d [ 17.246524] [<c1b5a0ac>] i386_start_kernel+0x9b/0xa2 [ 17.260655] OK This is IBM ThinkPad T43. Kernel compiled for i386 (IA-32), with -march=pentium-m. I think this is regression, because I didn't have this RCU warning with cpu_idle or vt_console_print/console_unlock, Kernel config attached. Full dmesg on request.