Hi folks. I at last year already caught bug with same signature at kvm subsystem in 4.18.0 rc8 kernel. It happened when I started virtual machine. And then Thomas Gleixner was fixed this bug [1]. But now issue with same trace happens when I launch ProtocaseDesigner (this is java application which helps design computer cases). If earlier it was clear that issue was refers to the KVM subsystem of the kernel. Now it is not clear to which subsystem this bug related. $ eu-addr2line -e /lib/debug/lib/modules/`uname -r`/vmlinux speculation_ctrl_update+0x164 arch/x86/kernel/process.c:371:10 eu-addr2line say that it occurs in `arch/x86/kernel/process.c` file. Can anyone look? [33873.126307] ======================================================== [33873.126308] WARNING: possible irq lock inversion dependency detected [33873.126311] 5.0.0-0.rc6.git1.1.fc30.x86_64 #1 Tainted: G C [33873.126312] -------------------------------------------------------- [33873.126314] java/12730 just changed the state of lock: [33873.126316] 000000001bf18d8d (&st->lock){+...}, at: speculation_ctrl_update+0x164/0x1d0 [33873.126324] but this lock was taken by another, HARDIRQ-safe lock in the past: [33873.126325] (&(&sighand->siglock)->rlock){-.-.} [33873.126326] and interrupts could create inverse lock ordering between them. [33873.126328] other info that might help us debug this: [33873.126329] Possible interrupt unsafe locking scenario: [33873.126330] CPU0 CPU1 [33873.126330] ---- ---- [33873.126331] lock(&st->lock); [33873.126333] local_irq_disable(); [33873.126334] lock(&(&sighand->siglock)->rlock); [33873.126335] lock(&st->lock); [33873.126336] [33873.126337] lock(&(&sighand->siglock)->rlock); [33873.126338] *** DEADLOCK *** [33873.126339] no locks held by java/12730. [33873.126340] the shortest dependencies between 2nd lock and 1st lock: [33873.126344] -> (&(&sighand->siglock)->rlock){-.-.} { [33873.126346] IN-HARDIRQ-W at: [33873.126350] _raw_spin_lock_irqsave+0x49/0x83 [33873.126353] __lock_task_sighand+0x85/0x180 [33873.126356] do_send_sig_info+0x35/0x90 [33873.126357] kill_pid_info+0x83/0x150 [33873.126361] it_real_fn+0x39/0xf0 [33873.126363] __hrtimer_run_queues+0x110/0x450 [33873.126365] hrtimer_interrupt+0x10e/0x240 [33873.126368] smp_apic_timer_interrupt+0x83/0x230 [33873.126369] apic_timer_interrupt+0xf/0x20 [33873.126371] IN-SOFTIRQ-W at: [33873.126373] _raw_spin_lock_irqsave+0x49/0x83 [33873.126375] __lock_task_sighand+0x85/0x180 [33873.126377] do_send_sig_info+0x35/0x90 [33873.126378] kill_pid_info+0x83/0x150 [33873.126380] it_real_fn+0x39/0xf0 [33873.126382] __hrtimer_run_queues+0x110/0x450 [33873.126384] hrtimer_interrupt+0x10e/0x240 [33873.126386] smp_apic_timer_interrupt+0x83/0x230 [33873.126388] apic_timer_interrupt+0xf/0x20 [33873.126390] __do_softirq+0xb5/0x46a [33873.126392] irq_exit+0x119/0x120 [33873.126394] do_IRQ+0x9d/0x120 [33873.126396] ret_from_intr+0x0/0x22 [33873.126398] cpuidle_enter_state+0xbf/0x470 [33873.126401] do_idle+0x1ec/0x280 [33873.126403] cpu_startup_entry+0x19/0x20 [33873.126406] start_kernel+0x52a/0x548 [33873.126409] secondary_startup_64+0xa4/0xb0 [33873.126410] INITIAL USE at: [33873.126412] _raw_spin_lock_irq+0x3d/0x80 [33873.126414] calculate_sigpending+0x22/0x40 [33873.126416] ret_from_fork+0x8/0x50 [33873.126417] } [33873.126420] ... key at: [] __key.68417+0x0/0x8 [33873.126421] ... acquired at: [33873.126423] speculation_ctrl_update+0x164/0x1d0 [33873.126425] speculation_ctrl_update_current+0x22/0x30 [33873.126428] ssb_prctl_set.part.0+0x1a/0x20 [33873.126430] arch_seccomp_spec_mitigate+0x25/0x50 [33873.126433] do_seccomp+0x8f1/0x960 [33873.126436] do_syscall_64+0x5c/0xa0 [33873.126438] entry_SYSCALL_64_after_hwframe+0x49/0xbe [33873.126439] -> (&st->lock){+...} { [33873.126441] HARDIRQ-ON-W at: [33873.126444] _raw_spin_lock+0x31/0x80 [33873.126446] speculation_ctrl_update+0x164/0x1d0 [33873.126448] speculation_ctrl_update_current+0x22/0x30 [33873.126449] arch_prctl_spec_ctrl_set+0xe5/0x110 [33873.126452] __x64_sys_prctl+0xce/0x53c [33873.126454] do_syscall_64+0x5c/0xa0 [33873.126455] entry_SYSCALL_64_after_hwframe+0x49/0xbe [33873.126457] INITIAL USE at: [33873.126459] _raw_spin_lock+0x31/0x80 [33873.126461] speculation_ctrl_update+0x164/0x1d0 [33873.126463] speculation_ctrl_update_current+0x22/0x30 [33873.126465] ssb_prctl_set.part.0+0x1a/0x20 [33873.126466] arch_seccomp_spec_mitigate+0x25/0x50 [33873.126468] do_seccomp+0x8f1/0x960 [33873.126470] do_syscall_64+0x5c/0xa0 [33873.126472] entry_SYSCALL_64_after_hwframe+0x49/0xbe [33873.126473] } [33873.126477] ... key at: [] __key.60803+0x0/0x8 [33873.126478] ... acquired at: [33873.126481] __lock_acquire+0x544/0x1660 [33873.126483] lock_acquire+0xa2/0x1b0 [33873.126485] _raw_spin_lock+0x31/0x80 [33873.126487] speculation_ctrl_update+0x164/0x1d0 [33873.126488] speculation_ctrl_update_current+0x22/0x30 [33873.126490] arch_prctl_spec_ctrl_set+0xe5/0x110 [33873.126492] __x64_sys_prctl+0xce/0x53c [33873.126494] do_syscall_64+0x5c/0xa0 [33873.126495] entry_SYSCALL_64_after_hwframe+0x49/0xbe [33873.126497] stack backtrace: [33873.126500] CPU: 5 PID: 12730 Comm: java Tainted: G C 5.0.0-0.rc6.git1.1.fc30.x86_64 #1 [33873.126502] Hardware name: System manufacturer System Product Name/ROG STRIX X470-I GAMING, BIOS 1103 11/16/2018 [33873.126504] Call Trace: [33873.126508] dump_stack+0x85/0xc0 [33873.126511] check_usage_backwards.cold+0x1d/0x26 [33873.126515] mark_lock+0x188/0x600 [33873.126518] ? print_shortest_lock_dependencies+0x40/0x40 [33873.126520] __lock_acquire+0x544/0x1660 [33873.126523] ? sched_clock+0x5/0x10 [33873.126525] ? sched_clock_cpu+0xc/0xc0 [33873.126528] lock_acquire+0xa2/0x1b0 [33873.126530] ? speculation_ctrl_update+0x164/0x1d0 [33873.126533] _raw_spin_lock+0x31/0x80 [33873.126535] ? speculation_ctrl_update+0x164/0x1d0 [33873.126537] speculation_ctrl_update+0x164/0x1d0 [33873.126540] speculation_ctrl_update_current+0x22/0x30 [33873.126542] arch_prctl_spec_ctrl_set+0xe5/0x110 [33873.126544] __x64_sys_prctl+0xce/0x53c [33873.126546] ? trace_hardirqs_off_thunk+0x1a/0x1c [33873.126549] do_syscall_64+0x5c/0xa0 [33873.126551] entry_SYSCALL_64_after_hwframe+0x49/0xbe [33873.126555] RIP: 0033:0x7f51369301ee [33873.126558] Code: 48 8b 0d 9d 3c 0c 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 9d 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 6a 3c 0c 00 f7 d8 64 89 01 48 [33873.126560] RSP: 002b:00007ffe0894f698 EFLAGS: 00000246 ORIG_RAX: 000000000000009d [33873.126562] RAX: ffffffffffffffda RBX: 00007f51366f60c8 RCX: 00007f51369301ee [33873.126564] RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000035 [33873.126565] RBP: 0000000000000003 R08: 0000000000000000 R09: 000055d7cfff1270 [33873.126566] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe08953da8 [33873.126568] R13: 000055d7cffee950 R14: 00007f51366f6198 R15: 0000000000000000 Thanks. [1] https://www.spinics.net/lists/kvm/msg173197.html -- Best Regards, Mike Gavrilov.