reboot / crash

[Der Geist der Maschine]

I got my 4th crash since Friday.

My Pinebook is barely usable. All browser usage crashes the OS and reboots. It started after updating to the latest updates. Maybe Winedivine had something to do with it?

I suggested already two times to provide debs for all of MrFixIT's updates. With debs we could easily and independently go back and forth new kernel versions, uboots and what else he provides.


I don't recall when I did what, but I *think* I got my first kernel crash before installing Winedivine.

Whoever created the Winedivine installer was sure that this is the greatest gift to mankind and did not provide an uninstaller. If you really want to uninstall Winedivine, perhaps uninstall chromium, delete all files left in /usr/lib/chromium-browser/ (that will be what the installer installed) and reinstall chromium, again.

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Anyone tried setting up kdump? I did. Just that it does not work.

1. I built a kernel with kdump support.

# zgrep -i KEXEC /proc/config.gz
CONFIG_KEXEC_CORE=y
CONFIG_KEXEC=y

2. It turns out that kdump-tools do not support aarch64:

# systemctl status kdump- kdump-tools.service - Kernel crash dump capture service
Loaded: loaded (/lib/systemd/system/kdump-tools.service; enabled; vendor preset: enabled)
Active: active (exited) since Thu 2019-11-07 20:34:43 PST; 1min 14s ago
Process: 3108 ExecStop=/etc/init.d/kdump-tools stop (code=exited, status=0/SUCCESS)
Process: 3138 ExecStart=/etc/init.d/kdump-tools start (code=exited, status=0/SUCCESS)
Main PID: 3138 (code=exited, status=0/SUCCESS)

Nov 07 20:34:43 pinebook-pro systemd[1]: Starting Kernel crash dump capture service...
Nov 07 20:34:43 pinebook-pro kdump-tools[3138]: Starting kdump-tools: Unsupported machine type: aarch64
Nov 07 20:34:43 pinebook-pro kdump-tools[3138]: failed to load kdump kernel ... failed!
Nov 07 20:34:43 pinebook-pro systemd[1]: Started Kernel crash dump capture service.


The unsupported message comes from kexec-tools: kexec/phys_arch.c. There is support for arm64 but not aarch64. What the heck is the difference? Just simply overwriting one string with the other is not enough as we then bail out in the syscall to the kernel.

kexec_load(0xebc08000, 3, [{buf=0xf5a0d008, bufsz=25827336, mem=0xebc08000, memsz=25829376}, {buf=0xab36c728, bufsz=102504, mem=0xf3731000, memsz=106496}, {buf=0xab36c320, bufsz=1024, mem=0xf3b00000, memsz=4096}], KEXEC_ARCH_ARM|KEXEC_ON_CRASH) = -1 EINVAL (Invalid argument)

Uh, why is flag to kexec_load KEXEC_ARCH_ARM and not KEXEC_ARCH_ARM64? I fixed that, too.

Now kdump is set up:

# kdump-config status
current state : ready to kdump
root@pinebook-pro:~# kdump-config show
DUMP_MODE: kdump
USE_KDUMP: 1
KDUMP_SYSCTL: kernel.panic_on_oops=1
KDUMP_COREDIR: /var/crash
crashkernel addr: 0xebc00000
/boot/Image.bak
kdump initrd:

current state: ready to kdump

kexec command:
/sbin/kexec -p --command-line="rw root=/dev/mmcblk1p2 rootwait rootfstype=ext4 init=/sbin/init coherent_pool=1M ethaddr=5e:1d:04:11:80:3f eth1addr=5e:1d:04:11:80:5f serial=8ac3cf935afdad1 cgroup_enable=cpuset cgroup_memory=1 cgroup_enable=memory swapaccount=1 zswap.enabled=1 video=HDMI-A-1:1920x1080@60 video=eDP-1:1920x1080@60 loglevel=3 vga=current earlycon=uart8250,mmio32,0xff1a0000 swiotlb=1 usbcore.autosuspend=-1 net.ifnames=0 irqpoll nr_cpus=1 nousb systemd.unit=kdump-tools.service ata_piix.prefer_ms_hyperv=0" /boot/Image.bak


When I manually crash the kernel with echo c > /proc/sysrq*, then kernel just freezes as if kdump is not set up. Damn. Let's see when I have time to look into that.

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In the meantime, when I don't use my laptop, I switch with CTL-ALT-F1 to the console. I also disabled the panic=10 auto reboot. So, if the kernel crashes while I'm on the console, I expect to see its backtrace.