Re: [Xen-devel] [PATCH v7 1/6] x86/domain: remove the 'oos_off' flag

[Paul Durrant <Paul.Durrant@xxxxxxxxxx>]

> -----Original Message-----
> From: Jan Beulich <jbeulich@xxxxxxxx>
> Sent: 02 September 2019 15:54
> To: Paul Durrant <Paul.Durrant@xxxxxxxxxx>
> Cc: Andrew Cooper <Andrew.Cooper3@xxxxxxxxxx>; George Dunlap 
> <George.Dunlap@xxxxxxxxxx>; Roger Pau
> Monne <roger.pau@xxxxxxxxxx>; xen-devel@xxxxxxxxxxxxxxxxxxxx; Tim (Xen.org) 
> <tim@xxxxxxx>; WeiLiu
> <wl@xxxxxxx>
> Subject: Re: [PATCH v7 1/6] x86/domain: remove the 'oos_off' flag
> 
> On 02.09.2019 16:21, Paul Durrant wrote:
> > Yes, the hap part stays put. The 'oos_off' part moves to x86 and arm can
> > be left alone because it already rejects flags != (hvm | hap).
> 
> But it may better reject the OOS flag _despite_ having only HVM guests,
> as long as there's no shadow mode there in the first place.
> 

The flag will be rejected. As I said (in abbreviated form), the test in the ARM 
code is:

if (config->flags != (XEN_DOMCTL_CDF_hvm_guest | XEN_DOMCTL_CDF_hap) )
        error...

So, any attempt to set XEN_DOMCTL_CDF_oos_off will already cause an error.

  Paul

> Jan
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel