Bug#603670: early kernel panic as node under kvm (div-by-zero in pvclock_tsc_khz)
On Thu, Nov 25, 2010 at 04:46:13PM +, Ben Hutchings wrote: On Tue, 2010-11-16 at 10:10 +0100, Stefan Bühler wrote: Package: linux-image-2.6.32-5-amd64 Version: 2.6.32-27 Severity: important Found: linux-image-2.6.30-2-amd64/2.6.30-8squeeze1 Found: linux-image-2.6.36-trunk-amd64/2.6.36-1~experimental.1 Hi, I get an early kernel panic when i try to run testing/unstable/experimental kernels in a vm under kvm. The physical host runs 2.6.32-5-amd64, and uses qemu-kvm/0.12.5+dfsg-4 with libvirt 0.8.3-4. The stable kernel does not panic: linux-image-2.6.26-2-amd64 2.6.26-25 Example log for 2.6.32-5-amd64 (experimental has similar backtrace); the panic is caused by a div-by-zero in pvclock_tsc_khz here (v2.6.36 source): I suspect that this is a bug in the host kernel's implementation of the pvclock (paravirtual clock), not the guest's use of it. The kernel from stable works because it doesn't attempt to use the pvclock interface. Unfortunately really isn't enough information logged for me to tell for sure. Could you test with Linux 2.6.36 in both host and guest? Stefan, did you test with more recent kernels? Cheers, Moritz -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Bug#603670: early kernel panic as node under kvm (div-by-zero in pvclock_tsc_khz)
On Tue, 2010-11-16 at 10:10 +0100, Stefan Bühler wrote: Package: linux-image-2.6.32-5-amd64 Version: 2.6.32-27 Severity: important Found: linux-image-2.6.30-2-amd64/2.6.30-8squeeze1 Found: linux-image-2.6.36-trunk-amd64/2.6.36-1~experimental.1 Hi, I get an early kernel panic when i try to run testing/unstable/experimental kernels in a vm under kvm. The physical host runs 2.6.32-5-amd64, and uses qemu-kvm/0.12.5+dfsg-4 with libvirt 0.8.3-4. The stable kernel does not panic: linux-image-2.6.26-2-amd64 2.6.26-25 Example log for 2.6.32-5-amd64 (experimental has similar backtrace); the panic is caused by a div-by-zero in pvclock_tsc_khz here (v2.6.36 source): I suspect that this is a bug in the host kernel's implementation of the pvclock (paravirtual clock), not the guest's use of it. The kernel from stable works because it doesn't attempt to use the pvclock interface. Unfortunately really isn't enough information logged for me to tell for sure. Could you test with Linux 2.6.36 in both host and guest? Ben. -- Ben Hutchings Once a job is fouled up, anything done to improve it makes it worse. signature.asc Description: This is a digitally signed message part
Bug#603670: early kernel panic as node under kvm (div-by-zero in pvclock_tsc_khz)
Hi again, with qemu-kvm from experimental (0.13.0+dfsg-2) you can use: -cpu kvm64,-kvmclock as kvm option to disable kvmclock. for libvirt use the following in your domain config: domain type='kvm' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0' ... qemu:commandline qemu:arg value='-cpu'/ qemu:arg value='kvm64,-kvmclock'/ /qemu:commandline /domain (You may have to replace kvm64 with another cpu model) I tried using clocksource= in the linux boot commandline, and had no luck with any value i tried. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Bug#603670: early kernel panic as node under kvm (div-by-zero in pvclock_tsc_khz)
Package: linux-image-2.6.32-5-amd64 Version: 2.6.32-27 Severity: important Found: linux-image-2.6.30-2-amd64/2.6.30-8squeeze1 Found: linux-image-2.6.36-trunk-amd64/2.6.36-1~experimental.1 Hi, I get an early kernel panic when i try to run testing/unstable/experimental kernels in a vm under kvm. The physical host runs 2.6.32-5-amd64, and uses qemu-kvm/0.12.5+dfsg-4 with libvirt 0.8.3-4. The stable kernel does not panic: linux-image-2.6.26-2-amd64 2.6.26-25 Example log for 2.6.32-5-amd64 (experimental has similar backtrace); the panic is caused by a div-by-zero in pvclock_tsc_khz here (v2.6.36 source): http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=arch/x86/kernel/pvclock.c;h=239427ca02af05f8671aacaf9820aa298e94bff1;hb=f6f94e2ab1b33f0082ac22d71f66385a60d8157f#l113 [0.00] kvm-clock: cpu 0, msr 0:14f1701, boot clock PANIC: early exception 00 rip 10:8102cd63 error 0 cr2 0 [0.00] Pid: 0, comm: swapper Not tainted 2.6.32-5-amd64 #1 [0.00] Call Trace: [0.00] [814f319e] ? early_idt_handler+0x5e/0x71 [0.00] [8102cd63] ? pvclock_tsc_khz+0x13/0x2a [0.00] [81503f17] ? kvmclock_init+0x133/0x18c [0.00] [8150ccbe] ? parse_crashkernel+0x46/0x23f [0.00] [814f75f8] ? setup_arch+0x8f6/0x9cb [0.00] [811f6a9f] ? extract_entropy+0x6a/0x125 [0.00] [814f3140] ? early_idt_handler+0x0/0x71 [0.00] [814f39d0] ? start_kernel+0xdb/0x3e8 [0.00] [814f33b7] ? x86_64_start_kernel+0xf9/0x106 [0.00] RIP pvclock_tsc_khz+0x13/0x2a Regards, Stefan Loading Linux 2.6.32-5-amd64 ... Loading initial ramdisk ... [0.00] Initializing cgroup subsys cpuset [0.00] Initializing cgroup subsys cpu [0.00] Linux version 2.6.32-5-amd64 (Debian 2.6.32-27) (m...@debian.org) (gcc version 4.3.5 (Debian 4.3.5-4) ) #1 SMP Sat Oct 30 14:18:21 UTC 2010 [0.00] Command line: BOOT_IMAGE=/vmlinuz-2.6.32-5-amd64 root=/dev/mapper/vg0-stefan ro single console=tty0 console=ttyS0,38400 earlyprintk=ttyS0 [0.00] KERNEL supported cpus: [0.00] Intel GenuineIntel [0.00] AMD AuthenticAMD [0.00] Centaur CentaurHauls [0.00] BIOS-provided physical RAM map: [0.00] BIOS-e820: - 0009f000 (usable) [0.00] BIOS-e820: 0009f000 - 000a (reserved) [0.00] BIOS-e820: 000f - 0010 (reserved) [0.00] BIOS-e820: 0010 - 3fffb000 (usable) [0.00] BIOS-e820: 3fffb000 - 4000 (reserved) [0.00] BIOS-e820: fffbc000 - 0001 (reserved) [0.00] bootconsole [earlyser0] enabled [0.00] DMI 2.4 present. [0.00] last_pfn = 0x3fffb max_arch_pfn = 0x4 [0.00] x86 PAT enabled: cpu 0, old 0x0, new 0x7010600070106 [0.00] init_memory_mapping: -3fffb000 [0.00] RAMDISK: 2f87f000 - 3003c109 [0.00] ACPI: RSDP 000f8830 00014 (v00 BOCHS ) [0.00] ACPI: RSDT 3fffde30 00034 (v01 BOCHS BXPCRSDT 0001 BXPC 0001) [0.00] ACPI: FACP 3e70 00074 (v01 BOCHS BXPCFACP 0001 BXPC 0001) [0.00] ACPI: DSDT 3fffdfd0 01E22 (v01 BXPC BXDSDT 0001 INTL 20090123) [0.00] ACPI: FACS 3e00 00040 [0.00] ACPI: SSDT 3fffdf90 00037 (v01 BOCHS BXPCSSDT 0001 BXPC 0001) [0.00] ACPI: APIC 3fffdeb0 00072 (v01 BOCHS BXPCAPIC 0001 BXPC 0001) [0.00] ACPI: HPET 3fffde70 00038 (v01 BOCHS BXPCHPET 0001 BXPC 0001) [0.00] No NUMA configuration found [0.00] Faking a node at -3fffb000 [0.00] Bootmem setup node 0 -3fffb000 [0.00] NODE_DATA [9000 - 00010fff] [0.00] bootmap [00011000 - 00018fff] pages 8 [0.00] (7 early reservations) == bootmem [00 - 003fffb000] [0.00] #0 [00 - 001000] BIOS data page == [00 - 001000] [0.00] #1 [006000 - 008000] TRAMPOLINE == [006000 - 008000] [0.00] #2 [000100 - 0001688414]TEXT DATA BSS == [000100 - 0001688414] [0.00] #3 [002f87f000 - 003003c109] RAMDISK == [002f87f000 - 003003c109] [0.00] #4 [09f000 - 10]BIOS reserved == [09f000 - 10] [0.00] #5 [0001689000 - 0001689071] BRK == [0001689000 - 0001689071] [0.00] #6 [008000 - 009000] PGTABLE == [008000 - 009000] [0.00] found SMP MP-table at [880f8880] f8880 [0.00] kvm-clock: cpu 0, msr 0:14f1701, boot clock PANIC: early exception 00 rip 10:8102cd63 error 0 cr2 0 [
