Re: [PATCH] xen: don't use privcmd_call() from xen_mc_flush()
From: Boris Ostrovsky
Date: Tue Aug 07 2018 - 12:41:55 EST
On 08/07/2018 11:17 AM, Juergen Gross wrote:
> On 07/08/18 16:02, Boris Ostrovsky wrote:
>> 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."
> This would be fine, thanks.
Applied to for-linus-4.19