Re: [PATCH 5/5] vsprintf: Make %pGp print the hex value

[Petr Mladek <pmladek@suse.com>]

On Tue 2021-10-12 19:26:47, Matthew Wilcox (Oracle) wrote:
> All existing users of %pGp want the hex value as well as the decoded
> flag names.  This looks awkward (passing the same parameter to printf
> twice), so move that functionality into the core.  If we want, we
> can make that optional with flag arguments to %pGp in the future.

It makes sense. Just the selftest code is pain, see below ;-)

> diff --git a/lib/test_printf.c b/lib/test_printf.c
> index 662c3785aa57..a60b1a749e87 100644
> --- a/lib/test_printf.c
> +++ b/lib/test_printf.c
> @@ -613,6 +613,10 @@ page_flags_test(int section, int node, int zone, int last_cpupid,
>  	bool append = false;
>  	int i;
>  
> +	for (i = 0; i < ARRAY_SIZE(values); i++)
> +		page_flags |= (values[i] & pft[i].mask) << pft[i].shift;

I can't get the idea behind this. IMHO, the value might be zero even
when the related flag is set.

And the %pGp code seems to always print page flags from
page_flags_fields[] when the field width is not zero.

Or do I misread the code?

Best Regards,
Petr