FYI, we noticed the below changes on https://git.kernel.org/pub/scm/linux/kernel/git/sergeh/linux-security 2016-03-18/nsroot commit e2469d8a216a31ec4616553a3a2b250f86f524e9 ("split out nsroot printing to its own fn") +------------------------------------------+------------+------------+ | | e2cdf823b9 | e2469d8a21 | +------------------------------------------+------------+------------+ | boot_successes | 4 | 5 | | boot_failures | 1 | 9 | | invoked_oom-killer:gfp_mask=0x | 1 | | | Mem-Info | 1 | | | Out_of_memory:Kill_process | 1 | | | backtrace:_do_fork | 1 | | | backtrace:SyS_clone | 1 | | | BUG:unable_to_handle_kernel | 0 | 9 | | Oops | 0 | 9 | | RIP:kernfs_path_from_node_locked | 0 | 9 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 9 | | backtrace:vfs_read | 0 | 9 | | backtrace:SyS_read | 0 | 9 | +------------------------------------------+------------+------------+ [ 11.258126] systemd-sysv-generator[97]: Ignoring K01watchdog symlink in rc6.d, not generating watchdog.service. [ 11.260270] systemd-fstab-generator[95]: Parsing /etc/fstab [ 11.298349] input: ImExPS/2 Generic Explorer Mouse as /devices/platform/i8042/serio1/input/input3 [ 11.964847] BUG: unable to handle kernel NULL pointer dereference at 0000000000000051 [ 11.968189] IP: [<ffffffff8126d8e7>] kernfs_path_from_node_locked+0x47/0x340 [ 11.970565] PGD 0 [ 11.971979] Oops: 0000 [#1] SMP [ 11.973873] Modules linked in: [ 11.975499] CPU: 1 PID: 1 Comm: systemd Not tainted 4.5.0-rc1-00010-ge2469d8 #3 [ 11.978546] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014 [ 11.981565] task: ffff880073420000 ti: ffff88007341c000 task.ti: ffff88007341c000 [ 11.984335] RIP: 0010:[<ffffffff8126d8e7>] [<ffffffff8126d8e7>] kernfs_path_from_node_locked+0x47/0x340 [ 11.987562] RSP: 0018:ffff88007341fcb8 EFLAGS: 00010002 [ 11.989266] RAX: 0000000000000001 RBX: ffff88007f4b5e88 RCX: 0000000000000000 [ 11.991282] RDX: 0000000000000000 RSI: ffff88007f85c880 RDI: 0000000000000001 [ 11.993447] RBP: ffff88007341fd00 R08: 0000000000000000 R09: ffffffff81bd599e [ 11.995614] R10: 0000000000ffff0a R11: 0000000000000001 R12: ffff88007f4b5e88 [ 11.997783] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 11.999959] FS: 00007fbaf9802880(0000) GS:ffff880076900000(0000) knlGS:0000000000000000 [ 12.003088] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 12.005056] CR2: 0000000000000051 CR3: 000000007f517000 CR4: 00000000000406e0 [ 12.007079] Stack: [ 12.008216] ffffffff81bd599e 0000000000000000 ffff88007f4ed000 002e2e2f00000000 [ 12.011405] ffff88007f4b5e88 0000000000000246 ffff88007f85c880 0000000000000000 [ 12.014596] 0000000000000000 ffff88007341fd38 ffffffff8126dc1e ffff88005a8c32a0 [ 12.017786] Call Trace: [ 12.019020] [<ffffffff8126dc1e>] kernfs_path_from_node+0x3e/0x60 [ 12.020866] [<ffffffff811074de>] cgroup_show_options+0x10e/0x2b0 [ 12.037731] [<ffffffff8126cb02>] kernfs_sop_show_options+0x32/0x40 [ 12.039828] [<ffffffff81232d49>] show_mountinfo+0x1d9/0x270 [ 12.041688] [<ffffffff812109e7>] m_show+0x17/0x20 [ 12.043313] [<ffffffff81215d24>] seq_read+0x2c4/0x3a0 [ 12.045004] [<ffffffff811f0ed8>] __vfs_read+0x28/0xd0 [ 12.046693] [<ffffffff813acd43>] ? security_file_permission+0xa3/0xc0 [ 12.048614] [<ffffffff811f1627>] ? rw_verify_area+0x57/0xd0 [ 12.050385] [<ffffffff811f1726>] vfs_read+0x86/0x130 [ 12.052055] [<ffffffff811f2726>] SyS_read+0x46/0xa0 [ 12.053707] [<ffffffff818daa2e>] entry_SYSCALL_64_fastpath+0x12/0x6d [ 12.055779] Code: 48 85 f6 48 89 55 c0 c7 45 d4 2f 2e 2e 00 0f 84 39 02 00 00 4c 39 e6 0f 84 4b 02 00 00 48 8b 7e 08 48 85 ff 48 89 f8 48 0f 44 c6 <48> 8b 50 50 49 8b 44 24 08 48 85 c0 48 89 c1 49 0f 44 cc 48 3b [ 12.069654] RIP [<ffffffff8126d8e7>] kernfs_path_from_node_locked+0x47/0x340 [ 12.071979] RSP <ffff88007341fcb8> [ 12.073503] CR2: 0000000000000051 [ 12.075007] ---[ end trace 357f81c3837373ff ]--- [ 12.076736] Kernel panic - not syncing: Fatal exception FYI, raw QEMU command line is: qemu-system-x86_64 -enable-kvm -cpu Haswell,+smep,+smap -kernel /pkg/linux/x86_64-rhel/gcc-4.9/e2469d8a216a31ec4616553a3a2b250f86f524e9/vmlinuz-4.5.0-rc1-00010-ge2469d8 -append 'root=/dev/ram0 user=lkp job=/lkp/scheduled/vm-kbuild-2G-10/rand_will-it-scale-pwrite3-debian-x86_64-2015-02-07.cgz-x86_64-rhel-e2469d8a216a31ec4616553a3a2b250f86f524e9-20160320-65737-119hv5w-0.yaml ARCH=x86_64 kconfig=x86_64-rhel branch=sergeh-security/2016-03-18/nsroot commit=e2469d8a216a31ec4616553a3a2b250f86f524e9 BOOT_IMAGE=/pkg/linux/x86_64-rhel/gcc-4.9/e2469d8a216a31ec4616553a3a2b250f86f524e9/vmlinuz-4.5.0-rc1-00010-ge2469d8 max_uptime=1500 RESULT_ROOT=/result/will-it-scale/pwrite3/vm-kbuild-2G/debian-x86_64-2015-02-07.cgz/x86_64-rhel/gcc-4.9/e2469d8a216a31ec4616553a3a2b250f86f524e9/0 LKP_SERVER=inn 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 rw ip=::::vm-kbuild-2G-10::dhcp' -initrd /fs/sda1/initrd-vm-kbuild-2G-10 -m 2048 -smp 2 -device e1000,netdev=net0 -netdev user,id=net0,hostfwd=tcp::23025-:22 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -drive file=/fs/sda1/disk0-vm-kbuild-2G-10,media=disk,if=virtio -drive file=/fs/sda1/disk1-vm-kbuild-2G-10,media=disk,if=virtio -drive file=/fs/sda1/disk2-vm-kbuild-2G-10,media=disk,if=virtio -drive file=/fs/sda1/disk3-vm-kbuild-2G-10,media=disk,if=virtio -drive file=/fs/sda1/disk4-vm-kbuild-2G-10,media=disk,if=virtio -drive file=/fs/sda1/disk5-vm-kbuild-2G-10,media=disk,if=virtio -drive file=/fs/sda1/disk6-vm-kbuild-2G-10,media=disk,if=virtio -pidfile /dev/shm/kboot/pid-vm-kbuild-2G-10 -serial file:/dev/shm/kboot/serial-vm-kbuild-2G-10 -daemonize -display none -monitor null Thanks, Kernel Test Robot