Re: [PATCH] mapletree-vs-khugepaged

From: Guenter Roeck
Date: Thu May 19 2022 - 17:42:29 EST


On 5/19/22 07:35, Liam Howlett wrote:
* Guenter Roeck <linux@xxxxxxxxxxxx> [220517 10:32]:

...

Another bisect result, boot failures with nommu targets (arm:mps2-an385,
m68k:mcf5208evb). Bisect log is the same for both.
...
# first bad commit: [bd773a78705fb58eeadd80e5b31739df4c83c559] nommu: remove uses of VMA linked list

I cannot reproduce this on my side, even with that specific commit. Can
you point me to the failure log, config file, etc? Do you still see
this with the fixes I've sent recently?


This was in linux-next; most recently with next-20220517.
I don't know if that was up-to-date with your patches.
The problem seems to be memory allocation failures.
A sample log is at
https://kerneltests.org/builders/qemu-m68k-next/builds/1065/steps/qemubuildcommand/logs/stdio
The log history at
https://kerneltests.org/builders/qemu-m68k-next?numbuilds=30
will give you a variety of logs.

The configuration is derived from m5208evb_defconfig, with initrd
and command line embedded in the image. You can see the detailed
configuration updates at
https://github.com/groeck/linux-build-test/blob/master/rootfs/m68k/run-qemu-m68k.sh

Qemu command line is

qemu-system-m68k -M mcf5208evb -kernel vmlinux \
-cpu m5208 -no-reboot -nographic -monitor none
-append "rdinit=/sbin/init console=ttyS0,115200"

with initrd from
https://github.com/groeck/linux-build-test/blob/master/rootfs/m68k/rootfs-5208.cpio.gz

I use qemu v6.2, but any recent qemu version should work.

Hope this helps,
Guenter