https://bugzilla.kernel.org/show_bug.cgi?id=198205 Bug ID: 198205 Summary: infinite loop in vmx_vcpu_run on x86_64 Product: Virtualization Version: unspecified Kernel Version: 4.14.6 Hardware: x86-64 OS: Linux Tree: Mainline Status: NEW Severity: high Priority: P1 Component: kvm Assignee: virtualization_kvm@xxxxxxxxxxxxxxxxxxxx Reporter: aeden@xxxxxxxxxxxxx Regression: No When I try to ssh into VM, a thread in QEMU 2.10.1 blocks on ioctl(cpu->kvm_fd, KVM_RUN, arg); and I can see that a kernel thread is running at 100% constantly in htop(1). The ssh command never succeeds, and all of my other ssh sessions in the VM become unresponsive. The only thing I can do is reboot the VM via libvirt. So far I've only seen this happen twice, while running a VM on this kernel version (4.14.6-1-ARCH) everyday. This time, I got a kernel backtrace via echo l > /proc/sysrq-trigger To me, kvm_intel doesn't look like it's making progress. Here's the stacktrace taken from dmesg(1): [96492.268071] sysrq: SysRq : Show backtrace of all active CPUs [96492.268072] NMI backtrace for cpu 3 [96492.268073] CPU: 3 PID: 26664 Comm: bash Tainted: G C 4.14.6-1-ARCH #1 [96492.268074] Hardware name: Gigabyte Technology Co., Ltd. Z170X-Gaming 7/Z170X-Gaming 7, BIOS F22f 06/28/2017 [96492.268074] Call Trace: [96492.268084] dump_stack+0x5c/0x85 [96492.268085] nmi_cpu_backtrace+0xbf/0xd0 [96492.268086] ? irq_force_complete_move+0x100/0x100 [96492.268087] nmi_trigger_cpumask_backtrace+0xea/0x130 [96492.268089] ? __handle_sysrq+0x83/0x140 [96492.268089] __handle_sysrq+0x83/0x140 [96492.268091] write_sysrq_trigger+0x2b/0x30 [96492.268092] proc_reg_write+0x3d/0x60 [96492.268093] __vfs_write+0x33/0x170 [96492.268095] ? set_close_on_exec+0x30/0x70 [96492.268096] vfs_write+0xad/0x1a0 [96492.268096] SyS_write+0x52/0xc0 [96492.268098] entry_SYSCALL_64_fastpath+0x1a/0xa5 [96492.268099] RIP: 0033:0x7fb7f123dab4 [96492.268099] RSP: 002b:00007fffe871cb18 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [96492.268100] RAX: ffffffffffffffda RBX: 0000000000000134 RCX: 00007fb7f123dab4 [96492.268100] RDX: 0000000000000002 RSI: 0000000002531260 RDI: 0000000000000001 [96492.268100] RBP: 00000000000000c8 R08: 000000000000000a R09: 000000000255ecb0 [96492.268101] R10: 000000000000000a R11: 0000000000000246 R12: 0000000000000000 [96492.268101] R13: 00007fffe871bf70 R14: 00007fffe871c100 R15: 00007fffe871bf70 [96492.268102] Sending NMI from CPU 3 to CPUs 0-2: [96492.268105] NMI backtrace for cpu 0 [96492.268106] CPU: 0 PID: 1457 Comm: CPU 1/KVM Tainted: G C 4.14.6-1-ARCH #1 [96492.268106] Hardware name: Gigabyte Technology Co., Ltd. Z170X-Gaming 7/Z170X-Gaming 7, BIOS F22f 06/28/2017 [96492.268106] task: ffff984898c06ac0 task.stack: ffffb61b82734000 [96492.268109] RIP: 0010:vmx_complete_atomic_exit+0x77/0xd0 [kvm_intel] [96492.268110] RSP: 0018:ffffb61b82737cf0 EFLAGS: 00000046 [96492.268110] RAX: 0000000080000202 RBX: 0000000000000000 RCX: ffff98493b9a8000 [96492.268111] RDX: 0000000000004404 RSI: 0000000000000001 RDI: ffff98493b9a8000 [96492.268111] RBP: ffff98493b9a8000 R08: 0000000000000000 R09: 0000000000000202 [96492.268111] R10: ffffffff9ad171b0 R11: ffffffff9b13c36d R12: 0000000080000200 [96492.268111] R13: 0000000080000202 R14: 0000000000000050 R15: 0000000000000000 [96492.268112] FS: 00007f18a3f63700(0000) GS:ffff98494ec00000(0000) knlGS:0000000000000000 [96492.268112] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [96492.268112] CR2: 000000000001d001 CR3: 00000003f7c5f003 CR4: 00000000003626f0 [96492.268113] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [96492.268113] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [96492.268113] Call Trace: [96492.268116] vmx_vcpu_run+0x305/0x4a0 [kvm_intel] [96492.268131] ? kvm_arch_vcpu_ioctl_run+0x538/0x1630 [kvm] [96492.268136] ? kvm_arch_vcpu_load+0x69/0x230 [kvm] [96492.268142] ? load_fixmap_gdt+0x30/0x40 [96492.268143] ? __vmx_load_host_state.part.84+0x120/0x1f0 [kvm_intel] [96492.268148] ? kvm_arch_vcpu_load+0x84/0x230 [kvm] [96492.268152] ? kvm_vcpu_ioctl+0x27e/0x5e0 [kvm] [96492.268156] ? kvm_vcpu_ioctl+0x27e/0x5e0 [kvm] [96492.268157] ? do_futex+0x429/0xa90 [96492.268158] ? do_vfs_ioctl+0xa1/0x610 [96492.268159] ? __fget+0x49/0xb0 [96492.268160] ? SyS_ioctl+0x74/0x80 [96492.268161] ? exit_to_usermode_loop+0x94/0xa0 [96492.268162] ? entry_SYSCALL_64_fastpath+0x1a/0xa5 [96492.268162] Code: 74 66 41 81 e4 00 07 00 80 66 83 fb 29 74 45 41 81 fd 12 03 00 80 74 3c 41 81 fc 00 02 00 80 75 af 48 89 ef e8 bb a7 d0 ff cd 02 <5b> 48 89 ef 5d 41 5c 41 5d e9 bb a7 d0 ff 66 83 fb 29 c7 87 8c [96492.268170] NMI backtrace for cpu 1 [96492.268171] CPU: 1 PID: 14521 Comm: Xorg Tainted: G C 4.14.6-1-ARCH #1 [96492.268171] Hardware name: Gigabyte Technology Co., Ltd. Z170X-Gaming 7/Z170X-Gaming 7, BIOS F22f 06/28/2017 [96492.268172] task: ffff98470c54db80 task.stack: ffffb61b81908000 [96492.268186] RIP: 0010:fw_domains_get+0x11e/0x1d0 [i915] [96492.268187] RSP: 0018:ffff98494ec83ec0 EFLAGS: 00000086 [96492.268187] RAX: 000057c25b5d24fb RBX: ffff98493bc88000 RCX: 000000000000001f [96492.268187] RDX: 0000000000000000 RSI: fffffffa093f71b2 RDI: 000000001fefa611 [96492.268188] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 [96492.268188] R10: ffff98494ec83ea0 R11: ffffb61b8190baf8 R12: ffff98493bc88728 [96492.268188] R13: 000057c25b5bf754 R14: 0000000000000000 R15: 00000000ffffffff [96492.268189] FS: 00007fc598d14940(0000) GS:ffff98494ec80000(0000) knlGS:0000000000000000 [96492.268189] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [96492.268189] CR2: 00007f5ea7ef93b8 CR3: 000000042d4c8002 CR4: 00000000003626e0 [96492.268190] Call Trace: [96492.268191] <IRQ> [96492.268201] intel_uncore_forcewake_get.part.8+0x41/0xa0 [i915] [96492.268210] intel_lrc_irq_handler+0x2c/0x370 [i915] [96492.268211] ? hrtimer_wakeup+0x1e/0x30 [96492.268212] ? ktime_get+0x3b/0x90 [96492.268213] tasklet_hi_action+0x59/0x110 [96492.268214] __do_softirq+0xd9/0x2da [96492.268215] do_softirq_own_stack+0x2a/0x40 [96492.268216] </IRQ> [96492.268216] do_softirq.part.17+0x49/0x50 [96492.268217] __local_bh_enable_ip+0x67/0x70 [96492.268225] i915_gem_do_execbuffer+0x794/0x10e0 [i915] [96492.268227] ? ___slab_alloc+0xf3/0x4b0 [96492.268228] ? ___slab_alloc+0xf3/0x4b0 [96492.268228] ? kmem_cache_free+0x1d1/0x1f0 [96492.268235] ? i915_gem_execbuffer2+0x5d/0x390 [i915] [96492.268242] ? i915_gem_execbuffer2+0x5d/0x390 [i915] [96492.268249] i915_gem_execbuffer2+0x1b7/0x390 [i915] [96492.268255] ? i915_gem_execbuffer+0x2d0/0x2d0 [i915] [96492.268265] drm_ioctl_kernel+0x59/0xb0 [drm] [96492.268269] drm_ioctl+0x2d5/0x370 [drm] [96492.268276] ? i915_gem_execbuffer+0x2d0/0x2d0 [i915] [96492.268276] ? hrtimer_start_range_ns+0x1b3/0x330 [96492.268278] do_vfs_ioctl+0xa1/0x610 [96492.268279] ? __sys_recvmsg+0x4e/0x90 [96492.268279] ? __sys_recvmsg+0x7d/0x90 [96492.268280] SyS_ioctl+0x74/0x80 [96492.268281] entry_SYSCALL_64_fastpath+0x1a/0xa5 [96492.268281] RIP: 0033:0x7fc596b11337 [96492.268282] RSP: 002b:00007fff81f349e8 EFLAGS: 00003246 ORIG_RAX: 0000000000000010 [96492.268282] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fc596b11337 [96492.268282] RDX: 00007fff81f34a20 RSI: 0000000040406469 RDI: 000000000000000d [96492.268283] RBP: 000055c3b68ed610 R08: 0000000000000000 R09: 00007fc598ddeee0 [96492.268283] R10: 0000000000003fb0 R11: 0000000000003246 R12: 000055c3b62eab10 [96492.268283] R13: 000055c3b65806c0 R14: 000000000000001d R15: 0000000000000000 [96492.268284] Code: 89 c5 eb 0d 4c 29 e8 48 3d 7f f0 fa 02 77 77 f3 90 65 8b 3d 7d 74 51 3f e8 40 98 5b df 41 8b 54 24 54 48 03 93 90 06 00 00 8b 12 <83> e2 01 74 d4 45 85 f6 75 95 8b 44 24 04 09 83 18 07 00 00 48 [96492.268292] NMI backtrace for cpu 2 skipped: idling at pc 0xffffffffa0678b05 Here's the QEMU stacktrace after attaching with gdb: #0 0x00007f18b08f0337 in ioctl () at /usr/lib/libc.so.6 #1 0x000055f01bb9589b in kvm_vcpu_ioctl () #2 0x000055f01bb959e2 in kvm_cpu_exec () #3 0x000055f01bb72fa5 in () #4 0x00007f18b0bc208a in start_thread () at /usr/lib/libpthread.so.0 #5 0x00007f18b08f942f in clone () at /usr/lib/libc.so.6 -- You are receiving this mail because: You are watching the assignee of the bug.
