Re: [lkp] [kallsyms] 06862f34f6: BUG: unable to handle kernel NULL pointer dereference at (null)

From: Ard Biesheuvel
Date: Fri Jan 22 2016 - 01:56:44 EST


On 22 January 2016 at 03:20, kernel test robot
<ying.huang@xxxxxxxxxxxxxxx> wrote:
> FYI, we noticed the below changes on
>
> https://git.linaro.org/people/ard.biesheuvel/linux-arm kallsyms-text-relative
> commit 06862f34f614bb6ff6a9fc9c4b0d849e2ee2018d ("kallsyms: add support for relative offsets in kallsyms address table")
>
>
> +-----------------------------------------------------------+------------+------------+
> | | 30f05309bd | 06862f34f6 |
> +-----------------------------------------------------------+------------+------------+
> | boot_successes | 0 | 0 |
> | boot_failures | 6 | 8 |
> | Kernel_panic-not_syncing:Attempted_to_kill_init!exitcode= | 4 | |
> | BUG:kernel_test_oversize | 2 | |
> | BUG:unable_to_handle_kernel | 0 | 8 |
> +-----------------------------------------------------------+------------+------------+
>
>
>
> [ 0.568228] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0
> [ 0.568971] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0, 1GB 0
> [ 0.569835] CPU: Intel Xeon E312xx (Sandy Bridge) (family: 0x6, model: 0x2a, stepping: 0x1)
> [ 0.598441] BUG: unable to handle kernel NULL pointer dereference at (null)
> [ 0.599646] IP:
> [ 0.599884] BUG: unable to handle kernel NULL pointer dereference at (null)
> [ 0.610184] IP:
> Elapsed time: 10
> qemu-system-x86_64 -enable-kvm -cpu SandyBridge -kernel /pkg/linux/x86_64-randconfig-s4-01220217/gcc-5/06862f34f614bb6ff6a9fc9c4b0d849e2ee2018d/vmlinuz-4.4.0-10063-g06862f34 -append 'root=/dev/ram0 user=lkp job=/lkp/scheduled/vm-kbuild-yocto-x86_64-62/bisect_boot-1-yocto-minimal-x86_64.cgz-x86_64-randconfig-s4-01220217-06862f34f614bb6ff6a9fc9c4b0d849e2ee2018d-20160122-39812-uowsx2-0.yaml ARCH=x86_64 kconfig=x86_64-randconfig-s4-01220217 branch=linux-devel/devel-spot-201601220143 commit=06862f34f614bb6ff6a9fc9c4b0d849e2ee2018d BOOT_IMAGE=/pkg/linux/x86_64-randconfig-s4-01220217/gcc-5/06862f34f614bb6ff6a9fc9c4b0d849e2ee2018d/vmlinuz-4.4.0-10063-g06862f34 max_uptime=600 RESULT_ROOT=/result/boot/1/vm-kbuild-yocto-x86_64/yocto-minimal-x86_64.cgz/x86_64-randconfig-s4-01220217/gcc-5/06862f34f614bb6ff6a9fc9c4b0d849e2ee2018d/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-yocto-x86_64-62::dhcp drbd.minor_count=8' -initrd /fs/sdg1/initrd-vm-kbuild-yocto-x86_64-62 -m 320 -smp 1 -device e1000,netdev=net0 -netdev user,id=net0 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -drive file=/fs/sdg1/disk0-vm-kbuild-yocto-x86_64-62,media=disk,if=virtio -pidfile /dev/shm/kboot/pid-vm-kbuild-yocto-x86_64-62 -serial file:/dev/shm/kboot/serial-vm-kbuild-yocto-x86_64-62 -daemonize -display none -monitor null
>

Hello Ying,

Thanks for the report. Is this a clean build? I cannot reproduce the
issue with the attached config. Do you have the vmlinux file available
for inspection?

Thanks,
Ard.