Analysing core dump with crash tool: ---- SYSTEM MAP: /boot/System.map-3.2.0-80-virtual DEBUG KERNEL: /usr/lib/debug/boot/vmlinux-3.2.0-82-virtual DUMPFILE: ./VmCore CPUS: 2 DATE: Sat Jun 6 00:23:24 2015 UPTIME: 1 days, 11:37:29 LOAD AVERAGE: 1.96, 1.11, 0.54 TASKS: 183 NODENAME: activemq2 RELEASE: 3.2.0-80-virtual VERSION: #116-Ubuntu SMP Mon Mar 23 17:28:52 UTC 2015 MACHINE: x86_64 (1799 Mhz) MEMORY: 4 GB PANIC: "[128249.422864] Kernel panic - not syncing: softlockup: hung tasks" PID: 6345 COMMAND: "java" TASK: ffff880037412de0 [THREAD_INFO: ffff880037694000] CPU: 0 STATE: TASK_RUNNING (PANIC) ---- PID: 6345 TASK: ffff880037412de0 CPU: 0 COMMAND: "java" #0 [ffff88011fc03cd0] machine_kexec at ffffffff8103970a ... #7 [ffff88011fc03fb0] apic_timer_interrupt at ffffffff81667b9e --- <IRQ stack> --- #8 [ffff880037695cd8] apic_timer_interrupt at ffffffff81667b9e [exception RIP: flush_tlb_others_ipi+290] RIP: ffffffff81046932 RSP: ffff880037695d88 RFLAGS: 00000202 RAX: 0000000000000002 RBX: ffff880117c06a00 RCX: 0000000000000002 RDX: 0000000000000002 RSI: 0000000000000040 RDI: 0000000000000296 RBP: ffff880037695db8 R8: ffffffff81e0d0a0 R9: 0000000000000040 R10: 0000000000000000 R11: ffff8801163df4d0 R12: ffff880037695d28 R13: 0000000000000000 R14: ffffffff81143575 R15: ffff880037695d68 ORIG_RAX: ffffffffffffff10 CS: 0010 SS: 0018 ----
It is clear that we are locked inside flush_tlb_others_ipi. Disassembling flush_tlb_others_ipi I could see we are locked inside a loop waiting for a cpumask to be emptied. This cpumask is emptied when all other CPUs received the IPI and processed the event "INVALIDATE_TLB_VECTOR_START" properly. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1467955 Title: Precise BUG: soft lockup in flush_tlb_others_ipi To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1467955/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
