Documentation/powerpc: Ultravisor API

[Ram Pai]

On Thu, Jul 30, 2020 at 12:35:38PM +0200, Julia Lawall wrote:
> The file Documentation/powerpc/ultravisor.rst contains:
> 
>     Only valid value(s) in ``flags`` are:
> 
>         * H_PAGE_IN_SHARED which indicates that the page is to be shared
> 	  with the Ultravisor.
> 
>         * H_PAGE_IN_NONSHARED indicates that the UV is not anymore
>           interested in the page. Applicable if the page is a shared page.
> 
> The flag H_PAGE_IN_SHARED exists in the Linux kernel
> (arch/powerpc/include/asm/hvcall.h), but the flag H_PAGE_IN_NONSHARED does
> not.  Should the documentation be changed in some way?

Currently the code assumes H_PAGE_IN_NONSHARED as !H_PAGE_IN_SHARED.

We need to patch the kernel to explicitly define the flag.
I will submit a patch towards this.

Thanks,
RP