Re: [PATCH] xen: don't use privcmd_call() from xen_mc_flush()

[Boris Ostrovsky]

On 08/07/2018 09:11 AM, Juergen Gross wrote:
> On 13/06/18 11:58, Juergen Gross wrote:
>> Using privcmd_call() for a singleton multicall seems to be wrong, as
>> privcmd_call() is using stac()/clac() to enable hypervisor access to
>> Linux user space.
>>
>> Add a new xen_single_call() function to be use for that purpose.
>>
>> Reported-by: Jan Beulich <jbeulich@xxxxxxxx>
>> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> Boris, any objections?


I think Jan wanted a change in commit message. I can commit with this:

"Using privcmd_call() for a singleton multicall seems to be wrong, as
 privcmd_call() is using stac()/clac() to enable hypervisor access to
 Linux user space.

 Even if currently not a problem (pv domains can't use SMAP while HVM
 and PVH domains can't use multicalls) things might change when
 PVH dom0 support is added to the kernel."


-boris