Re: [vlan_device_event] BUG: unable to handle kernel paging request at 6b6b6ccf

[Fengguang Wu]

> > Of course, if it's bisectable, that would be great too.
>
> Yes, bisect is on the way. So far it's bisecting in the 4.12 commits.

The bisect was unsuccessful due to an unrelated DRM_BOCHS oops in 4.11.
Disabling the buggy driver, I managed to reproduce the
vlan_device_event bug in 4.11. However only to find the older kernels
suffer from different kind of oops, which make the bisect troublesome.

% grep -E 'dmesg.(BUG|EIP)' v4.*/matrix.json
v4.10/matrix.json:  "dmesg.BUG:unable_to_handle_kernel": [
v4.10/matrix.json:  "dmesg.EIP:kobject_get": [
v4.10/matrix.json:  "dmesg.BUG:kernel_reboot-without-warning_in_test_stage": [
v4.11/matrix.json:  "dmesg.BUG:unable_to_handle_kernel": [
v4.11/matrix.json:  "dmesg.EIP:vlan_device_event": [
v4.8/matrix.json:  "dmesg.BUG:kernel_reboot-without-warning_in_early-boot_stage,last_printk:Decompressing_Linux": [
v4.9/matrix.json:  "dmesg.BUG:key_not_in.data": [

I'll try tuning kconfig to get a good bisect base.

Hopefully we'll make the coming RC releases free from such bisect
stoppers with better regression tracking and bisect automation.

Regards,
Fengguang