Package: xen-hypervisor-4.0-amd64Version: 4.0.1-4Severity: graveTags: squeezeJustification: causes data loss, migrations fail When migrating from a machine that has nonstop_tsc in /proc/cpuinfo (A) to a machine that does not have this flag (B), guests VM either get a kernel panic or most/all running processes report invalid opcodes in dmesg and crash. When migrating in the opposite direction (B -> A), there seems to be no issues.
The solution would seem to involve masking out cpu features, but I'm not sure entirely how to do this. There are red hat specific patches here for the same issue: https://bugzilla.redhat.com/show_bug.cgi?id=526862 and the issue is discussed here as well: https://bugzilla.redhat.com/show_bug.cgi?id=711322 https://bugzilla.redhat.com/show_bug.cgi?id=694492 xm dmesg doesn't show anything strange, but the guests need to be destroyed, or sometimes you can type reboot and it'll get a kernel panic and reboot itself. This link has some info on cpu masking but I'm not sure how to apply it my hosts for this flag (or whether it should be applied to guests or host?): http://zhigang.org/wiki/XenCPUID#cpuid-boot-options-definition A # cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 44 model name : Intel(R) Xeon(R) CPU E5620 @ 2.40GHz stepping : 2 cpu MHz : 2400.178 cache size : 12288 KB fpu : yes fpu_exception : yes cpuid level : 11 wp : yes flags : fpu de tsc msr pae mce cx8 apic sep mtrr mca cmov pat clflush acpi mmx fxsr sse sse2 ss ht syscall nx lm constant_tsc up rep_good nonstop_tsc aperfmperf pni pclmulqdq est ssse3 cx16 sse4_1 sse4_2 popcnt aes hypervisor lahf_lm ida arat bogomips : 4800.35 clflush size : 64 cache_alignment : 64 address sizes : 40 bits physical, 48 bits virtual power management: A # xm info | grep hw_caps hw_caps : bfebfbff:2c100800:00000000:00001f40:029ee3ff:00000000:00000001:00000000 B # cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 23 model name : Intel(R) Xeon(R) CPU X3350 @ 2.66GHz stepping : 7 cpu MHz : 2660.054 cache size : 6144 KB fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu de tsc msr pae mce cx8 apic sep mtrr mca cmov pat clflush acpi mmx fxsr sse sse2 ss ht syscall nx lm constant_tsc up rep_good aperfmperf pni est ssse3 cx16 sse4_1 hypervisor lahf_lm bogomips : 5320.10 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: B # xm info | grep hw_caps hw_caps : bfebfbff:20100800:00000000:00000940:0008e3fd:00000000:00000001:00000000 -- Marcus Furlong -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
