Something with Xen is unstable since upgrade to kernel 4.3.0.1. After 24 hours since last boot I suddenly on Dom0 get:
Jan 25 09:37:01 debian CRON[20287]: (root) CMD (if test -x /usr/sbin/apticron; then /usr/sbin/apticron --cron; else true; fi) Jan 25 09:37:52 debian kernel: [85204.136136] INFO: task xl:19753 blocked for more than 120 seconds. Jan 25 09:37:52 debian kernel: [85204.136179] Not tainted 4.3.0-1-amd64 #1 Jan 25 09:37:52 debian kernel: [85204.136202] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Jan 25 09:37:52 debian kernel: [85204.136240] xl D ffff88018f4ca0c0 0 19753 19749 0x00000000 Jan 25 09:37:52 debian kernel: [85204.136245] ffff8802080525c0 0000000000000286 ffff880179aca0c0 ffff8800744b0000 Jan 25 09:37:52 debian kernel: [85204.136249] ffff8800744afe00 ffffffff81d09114 ffff8802080525c0 00000000ffffffff Jan 25 09:37:52 debian kernel: [85204.136252] ffffffff81d09118 ffffffff8158113f ffffffff81d09110 ffffffff815813ca Jan 25 09:37:52 debian kernel: [85204.136255] Call Trace: Jan 25 09:37:52 debian kernel: [85204.136265] [] ? schedule+0x2f/0x70 Jan 25 09:37:52 debian kernel: [85204.136268] [] ? schedule_preempt_disabled+0xa/0x10 Jan 25 09:37:52 debian kernel: [85204.136271] [] ? __mutex_lock_slowpath+0xb4/0x120 Jan 25 09:37:52 debian kernel: [85204.136274] [] ? mutex_lock+0x1b/0x30 Jan 25 09:37:52 debian kernel: [85204.136280] [] ? xenbus_dev_request_and_reply+0x21/0x90 Jan 25 09:37:52 debian kernel: [85204.136284] [] ? xenbus_file_write+0x292/0x520 Jan 25 09:37:52 debian kernel: [85204.136289] [] ? __raw_callee_save___pv_queued_spin_unlock+0x11/0x20 Jan 25 09:37:52 debian kernel: [85204.136293] [] ? vfs_write+0xa1/0x190 Jan 25 09:37:52 debian kernel: [85204.136296] [] ? SyS_write+0x52/0xc0 Jan 25 09:37:52 debian kernel: [85204.136300] [] ? system_call_fast_compare_end+0xc/0x67 After this XL stack is unuseable until next reboot. All DomU guests continue to run fine. I have a cron task making "xentop -b -i 1" every 5 min. Stopping this remove above Call Trace messages, but XL still unuseable until reboot. Brgds Torben Schou Jensen
