http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=999

Summary: PAE dom0 keeps printing "Timer ISR/0: Time went backwards" Product: Xen Version: unstable Platform: Other OS/Version: All Status: NEW Severity: normal Priority: P1 Component: Hypervisor AssignedTo: xen-...@lists.xensource.com ReportedBy: yunf...@intel.com

Environment: ------------ Service OS (ia32/ia32e/IA64): PAE Guest OS (ia32/ia32e/IA64): Change Set: 15376 Hardware:

Bug detailed description: --------------------------

When I run regular nightly testing on PAE host, I found that xen0 will print call traces continuously. If this issue appear, the basic case can not pass, such as one_VMX, one_XENU. And xen0 reponse very slow this time. it appears very often but not every time. We met the issue on Fedora5 dom0.

Reproduce steps: ----------------

Current result: ----------------

Expected result: ----------------

Basic root-causing log: ----------------------

Timer ISR/0: Time went backwards: delta=-39995687 delta_cpu=50004313 shadow=0 off=3548840044663 processed=3548880000000 cpu_processed=3548790000000 0: 3548790000000 1: 3548880000000 printk: 137 messages suppressed. Timer ISR/1: Time went backwards: delta=-29997618 delta_cpu=80002382 shadow=0 off=3553870041177 processed=3553900000000 cpu_processed=3553790000000 0: 3553900000000 1: 3553790000000 printk: 86 messages suppressed. Timer ISR/1: Time went backwards: delta=-39996075 delta_cpu=60003925 shadow=0 off=3558800042007 processed=3558840000000 cpu_processed=3558740000000 0: 3558840000000 1: 3558740000000 printk: 115 messages suppressed. Timer ISR/1: Time went backwards: delta=-39996777 delta_cpu=60003223 shadow=0 off=3563820042663 processed=3563860000000 cpu_processed=3563760000000 0: 3563860000000 1: 3563760000000 printk: 171 messages suppressed. Timer ISR/1: Time went backwards: delta=-39996569 delta_cpu=50003431 shadow=0 off=3568800042278 processed=3568840000000 cpu_processed=3568750000000 0: 3568840000000 1: 3568750000000 printk: 92 messages suppressed. Timer ISR/1: Time went backwards: delta=-19996393 delta_cpu=80003607 shadow=0 off=3573870039962 processed=3573890000000 cpu_processed=3573790000000 0: 3573890000000 1: 3573790000000 printk: 81 messages suppressed. Timer ISR/1: Time went backwards: delta=-19996860 delta_cpu=40003140 shadow=0 off=3578850038647 processed=3578870000000 cpu_processed=3578810000000 0: 3578870000000 1: 3578810000000 printk: 81 messages suppressed.