On Fri, Feb 25, 2011 at 10:07:22AM +0100, Jean-Philippe Menil wrote: > Hi, > > Each time i try tou use vhost_net, i'm facing a kernel bug. > I do a "modprobe vhost_net", and start guest whith vhost=on. > > Following is a trace with a kernel 2.6.37, but i had the same > problem with 2.6.36 (cf https://lkml.org/lkml/2010/11/30/29). 2.6.36 had a theorectical race that could explain this, but it should be ok in 2.6.37. > > The bug only occurs whith vhost_net charged, so i don't know if this > is a bug in kvm module code or in the vhost_net code. It could be a bug in eventfd which is the interface used by both kvm and vhost_net. Just for fun, you can try 3.6.38 - eventfd code has been changed a lot in 2.6.38 and if it does not trigger there it's a hint that irqfd is the reason. > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.243100] BUG: unable to handle kernel paging request at > 0000000000002458 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.243250] IP: [<ffffffffa041aa8a>] kvm_set_irq+0x2a/0x130 [kvm] Could you run markup_oops/ ksymoops on this please? As far as I can see kvm_set_irq can only get a wrong kvm pointer. Unless there's some general memory corruption, I'd guess You can also try comparing the irqfd->kvm pointer in kvm_irqfd_assign irqfd_wakeup and kvm_set_irq in virt/kvm/eventfd.c. > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.243378] PGD 45d363067 PUD 45e77a067 PMD 0 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.243556] Oops: 0000 [#1] SMP > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.243692] last sysfs file: > /sys/devices/pci0000:00/0000:00:0d.0/0000:05:00.0/0000:06:00.0/irq > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ 685.243777] CPU 0 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.243820] Modules linked in: vhost_net macvtap macvlan tun > powernow_k8 mperf cpufreq_userspace cpufreq_stats cpufreq_powersave > cpufreq_ondemand fre > q_table cpufreq_conservative fuse xt_physdev ip6t_LOG > ip6table_filter ip6_tables ipt_LOG xt_multiport xt_limit xt_tcpudp > xt_state iptable_filter ip_tables x_tables nf_conntrack_tftp > nf_conntrack_ftp nf_connt > rack_ipv4 nf_defrag_ipv4 8021q bridge stp ext2 mbcache > dm_round_robin dm_multipath nf_conntrack_ipv6 nf_conntrack > nf_defrag_ipv6 kvm_amd kvm ipv6 snd_pcm snd_timer snd soundcore > snd_page_alloc tpm_tis tpm ps > mouse dcdbas tpm_bios processor i2c_nforce2 shpchp pcspkr ghes > serio_raw joydev evdev pci_hotplug i2c_core hed button thermal_sys > xfs exportfs dm_mod sg sr_mod cdrom usbhid hid usb_storage ses > sd_mod enclosu > re megaraid_sas ohci_hcd lpfc scsi_transport_fc scsi_tgt bnx2 > scsi_mod ehci_hcd [last unloaded: scsi_wait_scan] > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ 685.246123] > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] Pid: 10, comm: kworker/0:1 Not tainted > 2.6.37-dsiun-110105 #17 0K543T/PowerEdge M605 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] RIP: 0010:[<ffffffffa041aa8a>] [<ffffffffa041aa8a>] > kvm_set_irq+0x2a/0x130 [kvm] > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] RSP: 0018:ffff88045fc89d30 EFLAGS: 00010246 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] RAX: 0000000000000000 RBX: 000000000000001a RCX: > 0000000000000001 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] RDX: 0000000000000000 RSI: 0000000000000000 RDI: > 0000000000000000 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] RBP: 0000000000000000 R08: 0000000000000001 R09: > ffff880856a91e48 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] R10: 0000000000000000 R11: 00000000ffffffff R12: > 0000000000000000 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] R13: 0000000000000001 R14: 0000000000000000 R15: > 0000000000000000 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] FS: 00007f617986c710(0000) GS:ffff88007f800000(0000) > knlGS:0000000000000000 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] CR2: 0000000000002458 CR3: 000000045d197000 CR4: > 00000000000006f0 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] DR0: 0000000000000000 DR1: 0000000000000000 DR2: > 0000000000000000 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: > 0000000000000400 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] Process kworker/0:1 (pid: 10, threadinfo > ffff88045fc88000, task ffff88085fc53c30) > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ 685.246123] Stack: > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] ffff88045fc89fd8 00000000000119c0 ffff88045fc88010 > ffff88085fc53ee8 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] ffff88045fc89fd8 ffff88085fc53ee0 ffff88085fc53c30 > 00000000000119c0 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] 00000000000119c0 ffffffff8137f7ce ffff88007f80df40 > 00000000ffffffff > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] Call Trace: > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffff8137f7ce>] ? common_interrupt+0xe/0x13 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffffa041bc30>] ? irqfd_inject+0x0/0x50 [kvm] > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffffa041bc57>] ? irqfd_inject+0x27/0x50 [kvm] > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffffa041bc30>] ? irqfd_inject+0x0/0x50 [kvm] > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffff8106b6f2>] ? process_one_work+0x112/0x460 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffff8106be25>] ? worker_thread+0x145/0x410 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffff8103a3d0>] ? __wake_up_common+0x50/0x80 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffff8106bce0>] ? worker_thread+0x0/0x410 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffff8106bce0>] ? worker_thread+0x0/0x410 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffff8106f786>] ? kthread+0x96/0xa0 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffff81003ce4>] ? kernel_thread_helper+0x4/0x10 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffff8106f6f0>] ? kthread+0x0/0xa0 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] [<ffffffff81003ce0>] ? kernel_thread_helper+0x0/0x10 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] Code: ff 41 57 41 89 f7 41 56 41 55 41 89 cd 41 54 49 89 > fc 55 53 89 d3 48 81 ec 98 00 00 00 8b 15 c6 79 03 00 85 d2 0f 85 c4 > 00 00 00 <4 > 9> 8b 84 24 58 24 00 00 3b 98 28 01 00 00 73 5e 89 db 48 8b 84 > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] RIP [<ffffffffa041aa8a>] kvm_set_irq+0x2a/0x130 [kvm] > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] RSP <ffff88045fc89d30> > Feb 23 13:56:19 ayrshire.u06.univ-nantes.prive kernel: [ > 685.246123] CR2: 0000000000002458 > > > If someone can help me, on how to solve this. > > Regards. > begin:vcard > fn:Jean-Philippe Menil > n:Menil;Jean-Philippe > org;quoted-printable:Universit=C3=A9 de Nantes;IRTS > adr;dom:;;;Nantes > email;internet:jean-philippe.menil@xxxxxxxxxxxxxx > title:Reseau > tel;work:02.53.48.49.27 > tel;fax:02.53.48.49.97 > x-mozilla-html:FALSE > version:2.1 > end:vcard > > _______________________________________________ > Virtualization mailing list > Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx > https://lists.linux-foundation.org/mailman/listinfo/virtualization -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
