Hi Stephen, 0day kernel testing robot got the below dmesg and the first bad commit is git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master commit 8fe7fba50596a8efb6e1ef15b1b4890f95eeffcd Merge: 2ef44b3 d07b956 Author: Stephen Rothwell AuthorDate: Fri Feb 13 15:56:51 2015 +1100 Commit: Stephen Rothwell CommitDate: Fri Feb 13 15:56:51 2015 +1100 Merge branch 'akpm-current/current' Conflicts: arch/x86/include/asm/pgtable_64.h include/linux/memcontrol.h include/linux/mm.h include/linux/slab.h include/linux/swapops.h kernel/fork.c lib/Makefile mm/memcontrol.c mm/mprotect.c mm/slab.h mm/slab_common.c mm/swap.c scripts/module-common.lds +------------------------------------+------------+------------+------------+---------------+ | | 2ef44b3a9e | d07b956c65 | 8fe7fba505 | next-20150213 | +------------------------------------+------------+------------+------------+---------------+ | boot_successes | 60 | 60 | 0 | 0 | | boot_failures | 0 | 0 | 20 | 14 | | BUG:non-zero_nr_pmds_on_freeing_mm | 0 | 0 | 20 | 14 | +------------------------------------+------------+------------+------------+---------------+ [ 2.209695] debug: unmapping init [mem 0xffff88000ff75000-0xffff88000fffffff] [ 2.210862] debug: unmapping init [mem 0xffff8800103d1000-0xffff8800103fffff] [ 2.217056] random: init urandom read with 3 bits of entropy available [ 2.219092] BUG: non-zero nr_pmds on freeing mm: 2 [ 2.221865] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.224047] BUG: non-zero nr_pmds on freeing mm: 2 [ 2.225538] hostname (100) used greatest stack depth: 14200 bytes left [ 2.226392] BUG: non-zero nr_pmds on freeing mm: 4 [ 2.227118] mount (97) used greatest stack depth: 14104 bytes left [ 2.227811] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.228896] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.230337] BUG: non-zero nr_pmds on freeing mm: 2 [ 2.231197] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.233237] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.234339] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.235530] BUG: non-zero nr_pmds on freeing mm: 2 [ 2.237687] BUG: non-zero nr_pmds on freeing mm: 4 [ 2.240279] BUG: non-zero nr_pmds on freeing mm: 4 [ 2.241549] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.242726] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.243792] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.244839] BUG: non-zero nr_pmds on freeing mm: 2 [ 2.245741] BUG: non-zero nr_pmds on freeing mm: 4 [ 2.246546] BUG: non-zero nr_pmds on freeing mm: 3 /bin/sh: /proc/self/fd/9: No such file or directory [ 2.249348] BUG: non-zero nr_pmds on freeing mm: 4 [ 2.250126] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.251983] BUG: non-zero nr_pmds on freeing mm: 4 [ 2.253333] BUG: non-zero nr_pmds on freeing mm: 2 [ 2.255435] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.256551] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.259066] BUG: non-zero nr_pmds on freeing mm: 3 [ 2.260070] BUG: non-zero nr_pmds on freeing mm: 4 [ 2.260977] BUG: non-zero nr_pmds on freeing mm: 4 [ 2.262336] BUG: non-zero nr_pmds on freeing mm: 2 [ 2.264123] sh (122) used greatest stack depth: 13992 bytes left [ 2.264831] BUG: non-zero nr_pmds on freeing mm: 4 [ 2.266065] BUG: non-zero nr_pmds on freeing mm: 2 /bin/sh: /proc/self/fd/9: No such file or directory [ 2.268783] BUG: non-zero nr_pmds on freeing mm: 4 [ 2.269971] BUG: non-zero nr_pmds on freeing mm: 2 /bin/sh: /proc/self/fd/9: No such file or directory [ 2.272452] BUG: non-zero nr_pmds on freeing mm: 4 Elapsed time: 5 qemu-system-x86_64 -cpu kvm64 -enable-kvm -kernel /kernel/x86_64-randconfig-n0-02131024/8fe7fba50596a8efb6e1ef15b1b4890f95eeffcd/vmlinuz-3.19.0-g8fe7fba -append 'hung_task_panic=1 earlyprintk=ttyS0,115200 rd.udev.log-priority=err systemd.log_target=journal systemd.log_level=warning 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 link=/kbuild-tests/run-queue/kvm/x86_64-randconfig-n0-02131024/next:master:8fe7fba50596a8efb6e1ef15b1b4890f95eeffcd:bisect-linux-7/.vmlinuz-8fe7fba50596a8efb6e1ef15b1b4890f95eeffcd-20150213172638-7-client7 branch=next/master BOOT_IMAGE=/kernel/x86_64-randconfig-n0-02131024/8fe7fba50596a8efb6e1ef15b1b4890f95eeffcd/vmlinuz-3.19.0-g8fe7fba drbd.minor_count=8' -initrd /kernel-tests/initrd/quantal-core-x86_64.cgz -m 320 -smp 2 -net nic,vlan=1,model=e1000 -net user,vlan=1 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -pidfile /dev/shm/kboot/pid-quantal-client7-5 -serial file:/dev/shm/kboot/serial-quantal-client7-5 -daemonize -display none -monitor null git bisect start b8acf73194186a5cba86812eb4ba17b897f0e13e bfa76d49576599a4b9f9b7a71f23d73d6dcff735 -- git bisect good 15763db134dd60504dbd93137e6654f06d639acf # 15:04 20+ 0 Merge branch 'for-3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup git bisect good 6e822065fa5ce80b14e82948c86d91b1844a4092 # 16:13 20+ 0 Merge remote-tracking branch 'char-misc/char-misc-next' git bisect good e4bd2bf79cef1c75552eab6a8623a7005335b361 # 16:35 20+ 0 Merge remote-tracking branch 'clk/clk-next' git bisect good 806acae0b8ec190eacb14c5db56fa492353d8672 # 17:04 20+ 0 Merge remote-tracking branch 'y2038/y2038' git bisect bad 8fe7fba50596a8efb6e1ef15b1b4890f95eeffcd # 17:29 0- 20 Merge branch 'akpm-current/current' git bisect good 2ef44b3a9ead3e81621386b9227f3c12da95a05d # 18:07 20+ 0 Merge remote-tracking branch 'access_once/linux-next' git bisect good 9ddc30fda3048a05dfb377422a560709bfd6b95a # 18:28 20+ 0 x86-add-pmd_-for-thp-fix git bisect good 78baabee9d8ed5eca4d6c3e11282f131aad503d5 # 18:58 20+ 0 irq: use %*pb[l] to print bitmaps including cpumasks and nodemasks git bisect good df9fbe22ce6f7048ceb77c2ca72b27066ae75509 # 19:22 20+ 0 fs-befs-linuxvfsc-remove-unnecessary-casting-fix git bisect good 3a1f139f4faaa9e30d7d72f5328410b430f3f74e # 19:43 20+ 0 scripts/gdb: add cache for type objects git bisect good 97dc3f62c8f37795cdee3001e86c346dd7f7a879 # 20:09 20+ 0 scripts/gdb: add internal helper and convenience function for per-cpu lookup git bisect good 135b2593df87b40d0eab61d7e3183106ef622bdf # 20:26 20+ 0 scripts/gdb: convert ModuleList to generator function git bisect good e0c48fa7b961ea3e420c60fcddd3100b3413546a # 20:58 20+ 0 ipc,sem: use current->state helpers git bisect good b4970b267279135de6984f101bde0ad7c49bb619 # 21:20 20+ 0 samples-seccomp-improve-label-helper-fix git bisect good d07b956c650ad58a8ce00517515ebaf962e1f5c7 # 21:42 20+ 0 scripts/gdb: Add infrastructure # first bad commit: [8fe7fba50596a8efb6e1ef15b1b4890f95eeffcd] Merge branch 'akpm-current/current' git bisect good 2ef44b3a9ead3e81621386b9227f3c12da95a05d # 21:44 60+ 0 Merge remote-tracking branch 'access_once/linux-next' git bisect good d07b956c650ad58a8ce00517515ebaf962e1f5c7 # 21:46 60+ 0 scripts/gdb: Add infrastructure # extra tests on HEAD of next/master git bisect bad b8acf73194186a5cba86812eb4ba17b897f0e13e # 21:46 0- 14 Add linux-next specific files for 20150213 # extra tests on tree/branch next/master git bisect bad b8acf73194186a5cba86812eb4ba17b897f0e13e # 21:46 0- 14 Add linux-next specific files for 20150213 # extra tests on tree/branch linus/master # extra tests on tree/branch next/master git bisect bad b8acf73194186a5cba86812eb4ba17b897f0e13e # 22:02 0- 14 Add linux-next specific files for 20150213 This script may reproduce the error. ---------------------------------------------------------------------------- #!/bin/bash kernel=$1 initrd=quantal-core-x86_64.cgz wget --no-clobber https://github.com/fengguang/reproduce-kernel-bug/raw/master/initrd/$initrd kvm=( qemu-system-x86_64 -cpu kvm64 -enable-kvm -kernel $kernel -initrd $initrd -m 320 -smp 2 -net nic,vlan=1,model=e1000 -net user,vlan=1 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -serial stdio -display none -monitor null ) append=( hung_task_panic=1 earlyprintk=ttyS0,115200 rd.udev.log-priority=err systemd.log_target=journal systemd.log_level=warning debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 panic=-1 softlockup_panic=1 nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 console=ttyS0,115200 console=tty0 vga=normal root=/dev/ram0 rw drbd.minor_count=8 ) "${kvm[@]}" --append "${append[*]}" ---------------------------------------------------------------------------- Thanks, Fengguang