Re: [PATCH v2 00/48] ARM: PXA multiplatform support

Guenter Roeck
2022-05-03T02:55:46Z

On 5/2/22 14:03, Arnd Bergmann wrote:
> On Mon, May 2, 2022 at 10:35 PM Guenter Roeck <linux@roeck-us.net> wrote:
>> On 5/2/22 12:21, Arnd Bergmann wrote:
>>>
>>
>> To boot from initrd:
>>
>> qemu-system-arm -M z2 -kernel \
>> arch/arm/boot/zImage -no-reboot -initrd \
>> rootfs-armv5.cpio --append \
>> "panic=-1 slub_debug=FZPUA rdinit=/sbin/init console=ttyS0" -nographic \
>> -monitor null -serial stdio
>>
>> where rootfs-armv5.cpio is from my repository at github.com.
>>
>> https://github.com/groeck/linux-build-test/blob/master/rootfs/arm/rootfs-armv5.cpio.gz
>>
>
> Ok, that works here with any configuration, I don't see a regression.
> Could this be a problem with the size increase? The machine only has
> 32MB of RAM, so it's possible that the multiplatform-enabled kernel
> with DT support etc pushes it over the edge, especially with an initramfs.
>

qemu puts initrd in the middle of available memory. With the image size
being ~1MB larger than with v5.18-rc, this is too much, and the kernel
overwrites part of initrd. This causes it to be corrupted.

It looks like that would have happened eventually, your patch series just
made it happen now. The kernel is just getting too large to run on such small
systems. I worked around the problem in my version of qemu by loading initrd
at the end of the (small) RAM. With that, I no longer see the boot failure.

Guenter