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

From: Guenter Roeck
Date: Tue May 03 2022 - 10:05:10 EST


On 5/3/22 00:17, Arnd Bergmann wrote:
On Tue, May 3, 2022 at 4:55 AM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
On 5/2/22 14:03, Arnd Bergmann wrote:
On Mon, May 2, 2022 at 10:35 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
On 5/2/22 12:21, Arnd Bergmann wrote:

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.

Ok, thanks for confirming. If it's just the image size that changed,
then I think
we can live with it. Having the kernel image grow by 1MB seems excessive
though, I'd like to understand better where that increase comes from.

Starting out from pxa_defconfig, I see a 40KB increase from the final patch
that moves to multiplatform support, which I think is fine.

If you have a z2 specific config, that would probably not enable CONFIG_OF,
which is always turned on for multiplatform, but again that only adds around
250KB in my builds (using gcc-11). This is more than I'd like it to be, but
still much less than 1MB.


Maybe it is a bit less; I only compared the size of "Image". Either case,
it is enough to cause the problem. I am not sure if it is worth the time
trying to track this down further.

Guenter