Re: [PATCH v1 1/1] of: unittest: unflatten device tree on UML when testing

[Frank Rowand <frowand.list@gmail.com>]

On 2/12/19 10:53 AM, Brendan Higgins wrote:
> UML supports enabling OF, and is useful for running the device tree
> tests, so add support for unflattening device tree blobs so we can
> actually use it.
> 
> Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
> ---
>  drivers/of/unittest.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
> index 84427384654d5..effa4e2b9d992 100644
> --- a/drivers/of/unittest.c
> +++ b/drivers/of/unittest.c
> @@ -2527,6 +2527,9 @@ static int __init of_unittest(void)
>  	}
>  	of_node_put(np);
>  
> +	if (IS_ENABLED(CONFIG_UML))
> +		unflatten_device_tree();
> +
>  	pr_info("start of unittest - you will see error messages\n");
>  	of_unittest_check_tree_linkage();
>  	of_unittest_check_phandles();
> 

(Insert my usual disclaimer that I am clueless about UML, I still need to learn
about it...)

This does not look correct to me.

A few lines earlier in of_unittest(), the live devicetree needs to exist for
unittest_data_data() and a few of_*() functions to succeed.  So it seems
that the unflatten_device_tree() for uml should be at the beginning of
of_unittest().

Rob, if I am correct please revert this patch.

-Frank