Hi Marcelo, 0day kernel testing robot got the below dmesg and the first bad commit is git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master commit 3dc4f7cfb7441e5e0fed3a02fc81cdaabd28300a Author: Marcelo Tosatti AuthorDate: Tue Nov 27 23:28:56 2012 -0200 Commit: Marcelo Tosatti CommitDate: Tue Nov 27 23:29:10 2012 -0200 x86: kvm guest: pvclock vsyscall support Hook into generic pvclock vsyscall code, with the aim to allow userspace to have visibility into pvclock data. Signed-off-by: Marcelo Tosatti +--------------------------------------------------------------+------------+------------+ | | 71056ae22d | 3dc4f7cfb7 | +--------------------------------------------------------------+------------+------------+ | boot_successes | 60 | 0 | | boot_failures | 0 | 20 | | WARNING:at_arch/x86/kernel/pvclock.c:pvclock_init_vsyscall() | 0 | 20 | | backtrace:pvclock_init_vsyscall | 0 | 20 | | backtrace:warn_slowpath_null | 0 | 20 | | backtrace:kvm_setup_vsyscall_timeinfo | 0 | 20 | | backtrace:kvm_guest_init | 0 | 20 | +--------------------------------------------------------------+------------+------------+ [ 0.000000] mapped IOAPIC to ffffffffff5f8000 (fec00000) [ 0.000000] nr_irqs_gsi: 40 [ 0.000000] ------------[ cut here ]------------ [ 0.000000] WARNING: at arch/x86/kernel/pvclock.c:182 pvclock_init_vsyscall+0x21/0x59() [ 0.000000] Hardware name: Bochs [ 0.000000] Pid: 0, comm: swapper Not tainted 3.7.0-rc3-00112-g3dc4f7c #37 [ 0.000000] Call Trace: [ 0.000000] [] warn_slowpath_common+0x7c/0x94 [ 0.000000] [] warn_slowpath_null+0x1a/0x1c [ 0.000000] [] pvclock_init_vsyscall+0x21/0x59 [ 0.000000] [] kvm_setup_vsyscall_timeinfo+0x59/0x8b [ 0.000000] [] kvm_guest_init+0xe4/0xfe [ 0.000000] [] setup_arch+0xa64/0xad9 [ 0.000000] [] start_kernel+0xdc/0x430 [ 0.000000] [] ? early_idt_handlers+0x120/0x120 [ 0.000000] [] x86_64_start_reservations+0xb0/0xb3 [ 0.000000] [] x86_64_start_kernel+0x102/0x10f [ 0.000000] ---[ end trace c4149eb8555303de ]--- [ 0.000000] e820: [mem 0x14000000-0xfeffbfff] available for PCI devices git bisect start 749387dc8d8270b279f27a0a794cdf4f4a4aa774 v3.7 -- git bisect bad e32795503de02da4e7e74a5e039cc268f6a0ecfb # 23:38 0- 13 Merge tags 'dt-for-linus', 'gpio-for-linus' and 'spi-for-linus' of git://git.secretlab.ca/git/linux-2.6 git bisect bad e777d192ffb9f2929d547a2f8a5f65b7db7a9552 # 00:25 0- 4 Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi git bisect good 50851c6248e1a13c45d97c41f6ebcf716093aa5e # 00:43 20+ 0 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux git bisect good 698d601224824bc1a5bf17f3d86be902e2aabff0 # 01:11 20+ 0 Merge tag 'drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc git bisect good 8d9ea7172edd2e52da26b9485b4c97969a0d2648 # 01:34 20+ 0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net git bisect bad 66cdd0ceaf65a18996f561b770eedde1d123b019 # 01:57 0- 3 Merge tag 'kvm-3.8-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm git bisect good 3127f23f013eabe9b58132c05061684c49146ba3 # 02:12 20+ 0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k git bisect good c7708fac5a878d6e0f2de0aa19f9749cff4f707f # 02:31 20+ 0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux git bisect good 896ea17d3da5f44b2625c9cda9874d7dfe447393 # 02:42 20+ 0 Merge tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen git bisect good 8455d79e2163997e479931b8d5b7e60a92cd2b86 # 02:49 20+ 0 KVM: PPC: Book3S HV: Run virtual core whenever any vcpus in it can run git bisect bad 78c634402a1825f1f5bef13077f0985f3b8a3212 # 03:10 0- 6 kvm: deliver msi interrupts from irq handler git bisect good 189e11731aa858597095fbe1e6d243bad26bd96b # 03:44 20+ 0 x86: pvclock: add note about rdtsc barriers git bisect bad b48aa97e38206a84bf8485e7c553412274708ce5 # 04:09 0- 11 KVM: x86: require matched TSC offsets for master clock git bisect bad 886b470cb14733a0286e365c77f1844c240c33a4 # 04:33 0- 13 KVM: x86: pass host_tsc to read_l1_tsc git bisect good 71056ae22d43f58d7e0f793af18ace2eaf5b74eb # 04:58 20+ 0 x86: pvclock: generic pvclock vsyscall initialization git bisect bad 51c19b4f5927f5a646e93d69f73c7e89ea14e737 # 05:16 0- 15 x86: vdso: pvclock gettime support git bisect bad 3dc4f7cfb7441e5e0fed3a02fc81cdaabd28300a # 05:40 0- 6 x86: kvm guest: pvclock vsyscall support # first bad commit: [3dc4f7cfb7441e5e0fed3a02fc81cdaabd28300a] x86: kvm guest: pvclock vsyscall support git bisect good 71056ae22d43f58d7e0f793af18ace2eaf5b74eb # 05:42 60+ 0 x86: pvclock: generic pvclock vsyscall initialization git bisect good d67a0e110187abd560a1de63fa172894a52839d5 # 05:45 60+ 0 morphologies: Enable CONFIG_FHANDLE git bisect good 0e04c641b199435f3779454055f6a7de258ecdfc # 06:06 60+ 0 Merge tag 'dm-3.16-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm git bisect good b1cce620fd4b6864c92e7307be7839789f9c8be0 # 06:09 60+ 0 Add linux-next specific files for 20140612 This script may reproduce the error. ----------------------------------------------------------------------------- #!/bin/bash kernel=$1 initrd=yocto-minimal-x86_64.cgz wget --no-clobber https://github.com/fengguang/reproduce-kernel-bug/blob/master/initrd/$initrd kvm=( qemu-system-x86_64 -cpu kvm64 -enable-kvm -kernel $kernel -initrd $initrd -smp 2 -m 256M -net nic,vlan=0,macaddr=00:00:00:00:00:00,model=virtio -net user,vlan=0 -net nic,vlan=1,model=e1000 -net user,vlan=1 -boot order=nc -no-reboot -watchdog i6300esb -serial stdio -display none -monitor null ) append=( debug sched_debug apic=debug ignore_loglevel sysrq_always_enabled panic=10 prompt_ramdisk=0 earlyprintk=ttyS0,115200 console=ttyS0,115200 console=tty0 vga=normal root=/dev/ram0 rw ) "${kvm[@]}" --append "${append[*]}" ----------------------------------------------------------------------------- Thanks, Jet