Thanks for the heads-up. It's been running through XenServer's tests as well as the XenProject's "osstest" -- I haven't heard of any additional issues, but I'll ask.
Looks like I can reproduce this pretty easily, this happened upon ssh'ing into the server while I had a VM migrating into it. The system goes completely unresponsive (can't even enter a keystroke via console):
[64722.291300] vlan208: port 4(vif5.0) entered forwarding state [64722.291695] NOHZ: local_softirq_pending 08 [64929.006981] BUG: unable to handle kernel paging request at 0000000000002260 [64929.007020] IP: [<ffffffff81533a24>] n_tty_receive_buf_common+0xa4/0x1f0 [64929.007049] PGD 1f7a53067 [64929.007057] PUD 1ee0d4067 PMD 0 [64929.007069] [64929.007077] Oops: 0000 [#1] SMP [64929.007088] Modules linked in: ebt_ip6 ebt_ip ebtable_filter ebtables arptable_filter arp_tables bridge xen_pciback xen_gntalloc nfsd auth_rpcgss nfsv3 nfs_acl nfs fscache lockd sunrpc grace 8021q mrp garp stp llc bonding xen_acpi_processor blktap xen_netback xen_blkback xen_gntdev xen_evtchn xenfs xen_privcmd dcdbas fjes pcspkr ipmi_devintf ipmi_si ipmi_msghandler joydev i2c_i801 i2c_smbus lpc_ich shpchp mei_me mei ioatdma ixgbe mdio igb dca ptp pps_core uas usb_storage wmi ttm [64929.007327] CPU: 15 PID: 17696 Comm: kworker/u48:0 Not tainted 4.9.75-30.el6.x86_64 #1 [64929.007343] Hardware name: Dell Inc. PowerEdge C6220/03C9JJ, BIOS 2.7.1 03/04/2015 [64929.007362] Workqueue: events_unbound flush_to_ldisc [64929.007376] task: ffff8801fbc70580 task.stack: ffffc90048af8000 [64929.007415] RIP: e030:[<ffffffff81533a24>] [<ffffffff81533a24>] n_tty_receive_buf_common+0xa4/0x1f0 [64929.007465] RSP: e02b:ffffc90048afbb08 EFLAGS: 00010296 [64929.007476] RAX: 0000000000002260 RBX: 0000000000000000 RCX: 0000000000000002 [64929.007519] RDX: 0000000000000000 RSI: ffff8801dc0f3c20 RDI: ffff8801f9b8acd8 [64929.007563] RBP: ffffc90048afbb78 R08: 0000000000000001 R09: ffffffff8210f1c0 [64929.007577] R10: 0000000000007ff0 R11: 0000000000000000 R12: 0000000000000002 [64929.007620] R13: ffff8801f9b8ac00 R14: 0000000000000000 R15: ffff8801dc0f3c20 [64929.007675] FS: 00007fcfc0af8700(0000) GS:ffff880204dc0000(0000) knlGS:0000000000000000 [64929.007718] CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033 [64929.007759] CR2: 0000000000002260 CR3: 00000001f067b000 CR4: 0000000000042660 [64929.007782] Stack: [64929.007806] ffffc90048afbb38 0000000000000000 ffff8801f9b8acd8 0000000104dda030 [64929.007858] 0000000000002260 00000000fbc72700 ffff880204dc48c0 0000000000000000 [64929.007941] ffff880204dce890 ffff8801dc0f3c00 ffff8801f7f25c00 ffffc90048afbbf8 [64929.007994] Call Trace: [64929.008008] [<ffffffff81533b84>] n_tty_receive_buf2+0x14/0x20 [64929.008048] [<ffffffff81536763>] tty_ldisc_receive_buf+0x23/0x50 [64929.008088] [<ffffffff81536b88>] flush_to_ldisc+0xc8/0x100 [64929.008133] [<ffffffff8102eb7b>] ? __switch_to+0x20b/0x690 [64929.008176] [<ffffffff81025375>] ? xen_clocksource_read+0x15/0x20 [64929.008222] [<ffffffff810c0030>] process_one_work+0x170/0x500 [64929.008268] [<ffffffff818dac28>] ? __schedule+0x238/0x530 [64929.008310] [<ffffffff818db00a>] ? schedule+0x3a/0xa0 [64929.008324] [<ffffffff810c1ca6>] worker_thread+0x166/0x530 [64929.008368] [<ffffffff810e6a69>] ? put_prev_entity+0x29/0x140 [64929.008412] [<ffffffff818dac28>] ? __schedule+0x238/0x530 [64929.008458] [<ffffffff810d4082>] ? default_wake_function+0x12/0x20 [64929.008502] [<ffffffff810c1b40>] ? maybe_create_worker+0x120/0x120 [64929.008518] [<ffffffff818db00a>] ? schedule+0x3a/0xa0 [64929.008555] [<ffffffff818dedf6>] ? _raw_spin_unlock_irqrestore+0x16/0x20 [64929.008599] [<ffffffff810c1b40>] ? maybe_create_worker+0x120/0x120 [64929.008616] [<ffffffff810c6ae5>] kthread+0xe5/0x100 [64929.008630] [<ffffffff810d1a16>] ? schedule_tail+0x56/0xc0 [64929.008643] [<ffffffff810c6a00>] ? __kthread_init_worker+0x40/0x40 [64929.008659] [<ffffffff810d1a16>] ? schedule_tail+0x56/0xc0 [64929.008673] [<ffffffff818df5a1>] ret_from_fork+0x41/0x50 [64929.008685] Code: 89 fe 4c 89 ef 89 45 98 e8 aa fb ff ff 8b 45 98 48 63 d0 48 85 db 48 8d 0c 13 48 0f 45 d9 01 45 bc 49 01 d7 41 29 c4 48 8b 45 b0 <48> 8b 30 48 89 75 c0 49 8b 0e 8d 96 00 10 00 00 29 ca 41 f6 85 [64929.008894] RIP [<ffffffff81533a24>] n_tty_receive_buf_common+0xa4/0x1f0 [64929.008914] RSP <ffffc90048afbb08> [64929.008923] CR2: 0000000000002260 [64929.009641] ---[ end trace e1da1cdf77fed144 ]--- [64929.009785] BUG: unable to handle kernel paging request at ffffffffffffffd8 [64929.009804] IP: [<ffffffff810c62c0>] kthread_data+0x10/0x20 [64929.009823] PGD 200d067 [64929.009831] PUD 200f067 PMD 0 [64929.009842] [64929.009850] Oops: 0000 [#2] SMP [64929.009864] Modules linked in: ebt_ip6 ebt_ip ebtable_filter ebtables arptable_filter arp_tables bridge xen_pciback xen_gntalloc nfsd auth_rpcgss nfsv3 nfs_acl nfs fscache lockd sunrpc grace 8021q mrp garp stp llc bonding xen_acpi_processor blktap xen_netback xen_blkback xen_gntdev xen_evtchn xenfs xen_privcmd dcdbas fjes pcspkr ipmi_devintf ipmi_si ipmi_msghandler joydev i2c_i801 i2c_smbus lpc_ich shpchp mei_me mei ioatdma ixgbe mdio igb dca ptp pps_core uas usb_storage wmi ttm [64929.010054] CPU: 15 PID: 17696 Comm: kworker/u48:0 Tainted: G D 4.9.75-30.el6.x86_64 #1 [64929.010068] Hardware name: Dell Inc. PowerEdge C6220/03C9JJ, BIOS 2.7.1 03/04/2015 [64929.010127] task: ffff8801fbc70580 task.stack: ffffc90048af8000 [64929.010138] RIP: e030:[<ffffffff810c62c0>] [<ffffffff810c62c0>] kthread_data+0x10/0x20 [64929.010153] RSP: e02b:ffffc90048afbdd8 EFLAGS: 00010086 [64929.010162] RAX: 0000000000000000 RBX: ffff880204dd9fc0 RCX: 000000000000000f [64929.010174] RDX: ffff880200409400 RSI: ffff8801fbc70580 RDI: ffff8801fbc70580 [64929.010185] RBP: ffffc90048afbdd8 R08: ffff880204dc0000 R09: 00000006401f55c3 [64929.010197] R10: dead000000000200 R11: dead000000000200 R12: 0000000000019fc0 [64929.010208] R13: ffff8801fbc70580 R14: 0000000000000000 R15: ffff8801fbc70f40 [64929.010229] FS: 00007fcfc0af8700(0000) GS:ffff880204dc0000(0000) knlGS:0000000000000000 [64929.010241] CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033 [64929.010251] CR2: 0000000000000028 CR3: 00000001f067b000 CR4: 0000000000042660 [64929.010270] Stack: [64929.010275] ffffc90048afbe08 ffffffff810bda72 ffffc90048afbdf8 ffff880204dd9fc0 [64929.010295] 0000000000019fc0 ffff8801fbc70580 ffffc90048afbe78 ffffffff818dae04 [64929.010314] 0000000000000001 ffff8801ef0a2400 ffffc90048afbe48 ffff8801f0e67708 [64929.010333] Call Trace: [64929.010340] [<ffffffff810bda72>] wq_worker_sleeping+0x12/0xa0 [64929.010352] [<ffffffff818dae04>] __schedule+0x414/0x530 [64929.010362] [<ffffffff810d63ec>] do_task_dead+0x3c/0x40 [64929.010373] [<ffffffff810aaade>] do_exit+0x24e/0x480 [64929.010383] [<ffffffff810c6ae5>] ? kthread+0xe5/0x100 [64929.010393] [<ffffffff810d1a16>] ? schedule_tail+0x56/0xc0 [64929.010403] [<ffffffff810c6a00>] ? __kthread_init_worker+0x40/0x40 [64929.010415] [<ffffffff818e0db7>] rewind_stack_do_exit+0x17/0x20 [64929.010425] Code: 48 09 00 00 48 8b 40 c8 c9 48 c1 e8 02 83 e0 01 c3 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 66 66 66 66 90 48 8b 87 48 09 00 00 <48> 8b 40 d8 c9 c3 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 66 [64929.010607] RIP [<ffffffff810c62c0>] kthread_data+0x10/0x20 [64929.010620] RSP <ffffc90048afbdd8> [64929.010626] CR2: ffffffffffffffd8 [64929.010638] ---[ end trace e1da1cdf77fed145 ]--- [64929.010647] Fixing recursive fault but reboot is needed!
This is a centos 6 system booting with:
kernel /boot/xen.gz dom0_mem=6144M,max:6144M cpuinfo com1=115200,8n1 console=com1,tty loglvl=all guest_loglvl=all msi=off com2=115200,8n1 console=com2,tty1 module /boot/vmlinuz-4.9.75-30.el6.x86_64 ro root=UUID=ffab1fdf-28a4-4239-b112-5e920e3d6c36 rd_NO_LUKS rd_NO_LVM LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM biosdevname=0 nomodeset max_loop=128 max_loop=512 xencons=ttyS1 console=hvc0,tty0 module /boot/initramfs-4.9.75-30.el6.x86_64.img
Running xen-4.6.6-9.el6. Note that I have msi=off set in the xen parameters due to hitting the same network card bug that Kevin Stange was hitting.
Happy to grab any further info as required, or let me know if this is better suited on xen-devel.
Cheers, Nathan