Re: [PATCH v8 8/8] clk: Add KUnit tests for clks registered with struct clk_parent_data

[Guenter Roeck]

On 10/8/24 16:12, Stephen Boyd wrote:
> Quoting Guenter Roeck (2024-10-03 21:52:09)
> > On 10/3/24 17:42, Stephen Boyd wrote:
> > > Can you please describe how you run the kunit test? And provide the qemu
> > > command you run to boot arm64 with acpi?
> >
> > Example command line:
> >
> > qemu-system-aarch64 -M virt -m 512 \
> >        -kernel arch/arm64/boot/Image -no-reboot -nographic \
> >        -snapshot \
> >        -bios /opt/buildbot/rootfs/arm64/../firmware/QEMU_EFI-aarch64.fd \
> >        -device virtio-blk-device,drive=d0 \
> >        -drive file=rootfs.ext2,if=none,id=d0,format=raw \
> >        -cpu cortex-a57 -serial stdio -monitor none -no-reboot \
> >        --append "kunit.stats_enabled=2 kunit.filter=speed>slow root=/dev/vda rootwait earlycon=pl011,0x9000000 console=ttyAMA0"
> >
> > That works fine for me. Configuration is arm64 defconfig plus various
> > debug and kunit options. I built the efi image myself from sources.
> > The root file system is from buildroot with modified init script.
> > kunit tests are all built into the kernel and run during boot.
>
> Thanks. I figured out that I was missing enabling CONFIG_ACPI. Here's my
> commandline
>
> ./tools/testing/kunit/kunit.py run --arch=arm64 \
> 	--kunitconfig=drivers/of \
> 	--qemu_args="-bios /usr/share/qemu-efi-aarch64/QEMU_EFI.fd -smp 2" \
> 	--kconfig_add="CONFIG_ACPI=y" \
> 	--kernel_args="earlycon=pl011,0x9000000"
>
> Now I can boot and reproduce the failure, but there's another problem.
> ACPI disables itself when it fails to find tables.
>
>   ACPI: Unable to load the System Description Tables
>
> This calls disable_acpi() which sets acpi_disabled to 1. This happens
> before the unit test runs, meaning we can't reliably use 'acpi_disabled'
> as a method to skip.
>
> The best I can come up with then is to test for a NULL of_root when
> CONFIG_ARM64 and CONFIG_ACPI are enabled, because the tests
> intentionally don't work when both those configs are enabled and the
> 'of_root' isn't populated. In all other cases the 'of_root' missing is a
> bug. I'll probably make this into some sort of kunit helper function in
> of_private.h and send it to DT maintainers.

Sounds good. Thanks a lot for tracking this down.

That makes me wonder though why only arm64 has that restriction. Both
riscv and loongarch have ACPI enabled in their defconfig files but call
unflatten_device_tree() unconditionally.

Oh well ...

Thanks,
Guenter