Greetings, 0day kernel testing robot got the below dmesg and the first bad commit is https://github.com/0day-ci/linux Alexander-Kuleshov/clocksource-use-clocksource_freq2mult-helper/20160316-182426 commit 0639d1b7c6616200678c790969ad0a6fecddcd7f Author: Alexander Kuleshov <kuleshovmail(a)gmail.com&gt; AuthorDate: Wed Mar 16 16:21:15 2016 +0600 Commit: 0day robot <fengguang.wu(a)intel.com&gt; CommitDate: Wed Mar 16 18:24:28 2016 +0800 clocksource: use clocksource_freq2mult() helper which is introduced in the 7aca0c072 commit to simplify calculation of the mult and shift in the clocks_calc_mult_shift(). Signed-off-by: Alexander Kuleshov <kuleshovmail(a)gmail.com&gt; +-------------------------------------------------------+------------+------------+------------+ | | 6436257b49 | 0639d1b7c6 | b7c14ef7b3 | +-------------------------------------------------------+------------+------------+------------+ | boot_successes | 61 | 0 | 0 | | boot_failures | 5 | 22 | 13 | | BUG:unable_to_handle_kernel | 5 | | | | Oops | 5 | | | | EIP_is_at_perf_prepare_sample | 5 | | | | Kernel_panic-not_syncing:Fatal_exception_in_interrupt | 2 | | | | Kernel_panic-not_syncing:Fatal_exception | 3 | | | | backtrace:iterate_dir | 1 | | | | backtrace:SyS_getdents64 | 1 | | | | backtrace:vfs_fstatat | 2 | | | | backtrace:SyS_fstatat64 | 2 | | | | BUG:Int#:CR2(null) | 0 | 22 | 13 | | backtrace:__clocksource_register_scale | 0 | 22 | 13 | | backtrace:kvmclock_init | 0 | 22 | 13 | +-------------------------------------------------------+------------+------------+------------+ [ 0.000000] kvm-clock: Using msrs 4b564d01 and 4b564d00 [ 0.000000] kvm-clock: cpu 0, msr 0:fcac001, primary cpu clock [ 0.000000] kvm-clock: using sched offset of 3492090617 cycles [ 0.000000] BUG: Int 0: CR2 (null) [ 0.000000] EDI (null) ESI (null) EBP cb8a1f4c EBX cb8d3284 [ 0.000000] ESP cb8a1f2c ES 0000007b DS 0000007b [ 0.000000] EDX (null) ECX (null) EAX ffffffff [ 0.000000] vec (null) err (null) EIP ca9a33d6 CS 00000060 flg 00210046 [ 0.000000] Stack: ffffffff 00000020 ffffffff ffffffff (null) cb8d3260 cb8d3284 3b9aca00 [ 0.000000] cb8a1f78 ca9a3663 ffffffff ffffffff cb8d3284 ffffffff ffffffff 00000001 [ 0.000000] cb8d3260 a08baba0 cfcad000 cb8a1f88 ca9a36d2 (null) a08baba0 cb8a1f9c [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.5.0-rc1-00028-g0639d1b #56 [ 0.000000] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014 [ 0.000000] 00000000 00000000 cb8a1edc cae6ae2c cb8d3284 cb8a1f4c cba5b1d7 cbb02015 [ 0.000000] 00000000 00000000 00000000 00000000 cb8a1f4c cb8d3284 cb8a1f2c 0000007b [ 0.000000] 0000007b 00000000 00000000 ffffffff 00000000 00000000 ca9a33d6 00000060 [ 0.000000] Call Trace: [ 0.000000] [<cae6ae2c>] dump_stack+0xb8/0x108 [ 0.000000] [<cba5b1d7>] early_idt_handler_common+0x6b/0x6b [ 0.000000] [<ca9a33d6>] ? clocks_calc_max_nsecs+0x38/0xb9 [ 0.000000] [<ca9a3663>] __clocksource_update_freq_scale+0x20c/0x261 [ 0.000000] [<ca9a36d2>] __clocksource_register_scale+0x1a/0x13c [ 0.000000] [<cba7f2de>] kvmclock_init+0x372/0x392 [ 0.000000] [<cba616c3>] setup_arch+0x113d/0x131f [ 0.000000] [<cba5c156>] start_kernel+0x38a/0xc20 [ 0.000000] [<cba5b341>] i386_start_kernel+0x10f/0x121 Elapsed time: 10 Linux version 4.5.0-rc1-00028-g0639d1b #56 git bisect start b7c14ef7b333b48f6efb30edd3f9c74b2c731d08 8559bac87dcf580b62d5cc751f5ab62d01832744 -- git bisect bad 2d0ae075c59d6cbd0c8b8ac342ccd566bc023d89 # 19:11 0- 22 Merge 'asoc/for-linus' into devel-catchup-201603161845 git bisect good b6918d92076b1e3c4e5232d75e5fba748bbef280 # 19:23 22+ 0 Merge 'linux-review/Michael-Ellerman/powerpc-Remove-orphaned-asm-implementation-of-abs/20160316-184144' into devel-catchup-201603161845 git bisect good 1b513f4682020d55a79f500b7b3bb27d73367472 # 19:30 21+ 1 Merge 'linux-review/Jani-Nikula/drm-i915-dsi-lose-the-loose-666-format-name-in-favor-of-packed/20160316-182542' into devel-catchup-201603161845 git bisect bad 24c03fe798ed6484640cde73a6f11cc875b9411f # 19:36 0- 22 Merge 'linux-review/Shawn-Lin/mmc-block-fix-ABI-regression-of-mmc_blk_ioctl/20160316-182008' into devel-catchup-201603161845 git bisect bad 00575a1a3545c6934b66210f5d8026a2e9fae7aa # 19:44 0- 22 Merge 'linux-review/Alexander-Kuleshov/clocksource-use-clocksource_freq2mult-helper/20160316-182426' into devel-catchup-201603161845 git bisect bad 0639d1b7c6616200678c790969ad0a6fecddcd7f # 19:50 0- 19 clocksource: use clocksource_freq2mult() helper # first bad commit: [0639d1b7c6616200678c790969ad0a6fecddcd7f] clocksource: use clocksource_freq2mult() helper git bisect good 6436257b491cc0d456c39330dfc22126148d5ed7 # 20:05 65+ 5 time/timekeeping: Work around false positive GCC warning # extra tests with DEBUG_INFO git bisect bad 0639d1b7c6616200678c790969ad0a6fecddcd7f # 20:11 0- 66 clocksource: use clocksource_freq2mult() helper # extra tests on HEAD of linux-devel/devel-catchup-201603161845 git bisect bad b7c14ef7b333b48f6efb30edd3f9c74b2c731d08 # 20:11 0- 13 0day head guard for 'devel-catchup-201603161845' # extra tests on tree/branch linux-review/Alexander-Kuleshov/clocksource-use-clocksource_freq2mult-helper/20160316-182426 git bisect bad 0639d1b7c6616200678c790969ad0a6fecddcd7f # 20:15 0- 22 clocksource: use clocksource_freq2mult() helper # extra tests with first bad commit reverted git bisect good 2abf2c7c0ba89ac94ea62d520dc52b651a2e1b91 # 20:23 66+ 2 Revert "clocksource: use clocksource_freq2mult() helper" # extra tests on tree/branch linus/master git bisect good 9256d5a308c95a50c6e85d682492ae1f86a70f9b # 20:26 60+ 1 Merge tag 'leds_for_4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds # extra tests on tree/branch linux-next/master git bisect good 8559bac87dcf580b62d5cc751f5ab62d01832744 # 20:30 65+ 4 Add linux-next specific files for 20160316 This script may reproduce the error. ---------------------------------------------------------------------------- #!/bin/bash kernel=$1 kvm=( qemu-system-x86_64 -enable-kvm -cpu Haswell,+smep,+smap -kernel $kernel -m 256 -smp 1 -device e1000,netdev=net0 -netdev user,id=net0 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -serial stdio -display none -monitor null ) append=( hung_task_panic=1 earlyprintk=ttyS0,115200 systemd.log_level=err debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 panic=-1 softlockup_panic=1 nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 console=ttyS0,115200 console=tty0 vga=normal root=/dev/ram0 rw drbd.minor_count=8 ) "${kvm[@]}" --append "${append[*]}" ---------------------------------------------------------------------------- --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/lkp Intel Corporation