Re: [PATCH RFC] misc/pvpanic: add support for normal shutdowns

[Arnd Bergmann]

On Wed, Feb 28, 2024, at 07:48, Thomas Weißschuh wrote:
> Hi Michael,
>
> On 2024-02-13 05:41:48-0500, Michael S. Tsirkin wrote:
>> On Sat, Nov 04, 2023 at 02:05:02PM +0100, Greg Kroah-Hartman wrote:
>> > > diff --git a/include/uapi/misc/pvpanic.h b/include/uapi/misc/pvpanic.h
>> > > index 54b7485390d3..82fc618bfbcf 100644
>> > > --- a/include/uapi/misc/pvpanic.h
>> > > +++ b/include/uapi/misc/pvpanic.h
>> > > @@ -5,5 +5,6 @@
>> > >  
>> > >  #define PVPANIC_PANICKED	(1 << 0)
>> > >  #define PVPANIC_CRASH_LOADED	(1 << 1)
>> > > +#define PVPANIC_SHUTDOWN	(1 << 2)
>> > 
>> > Why are these in a uapi file?
>> > 
>> > And if they need to be here, why not use the proper BIT() macro for it?
>> > 
>> 
>> This is interface with hypervisor not userspace, but for PV historically
>> we do this since the compatibility implications are about the same,
>> hypervisors (e.g. QEMU) are mostly userspace and so it is convenient for
>> them to reuse the same machinery to export the headers.
>> 
>> Let's stick to that, cleaner than duplicating everything I think.
>
> as Greg seems to be busy with other stuff I'd like to go ahead with
> submitting this again using the existing header file.

FWIW, I agree using the uapi header for APIs shared between
kernel and qemu is fine, and we don't really have any other
place for those, so please add

Acked-by: Arnd Bergmann <arnd@xxxxxxxx>