Re: [PATCH v5 01/13] KVM: s390: Interface to test whether APXA installed

Tony Krowiak
2018-05-16T10:45:54Z

On 05/16/2018 06:21 AM, Cornelia Huck wrote:
> On Mon, 7 May 2018 11:11:40 -0400
> Tony Krowiak <akrowiak@linux.vnet.ibm.com> wrote:
>
>> Relocates an existing static function that tests whether
>> the AP extended addressing facility (APXA) is installed on
>> the linux host. The primary reason for relocating this
>> function is because a new compilation unit (arch/s390/kvm/kvm-ap.c)
>> is being created to contain all of the interfaces and logic
>> for configuring an AP matrix for a KVM guest. Some of its
>> functions will also need to determine whether APXA is installed,
>> so, let's go ahead and relocate this static function as a
>> public interface in kvm-ap.c.
>>
>> Notes:
>> ----
>> 1. The interface to determine whether APXA is installed on the linux
>> host the information returned from the AP Query Configuration
>> Information (QCI) function. This function will not be available
>> if the AP instructions are not installed on the linux host, so a check
>> will be included to verify that.
>>
>> 2. Currently, the AP bus interfaces accessing the AP instructions will
>> not be accessible if CONFIG_ZCRYPT=n, so the relevant code will be
>> temporarily contained in the new arch/s390/kvm/kvm-ap.c file until
>> the patch(es) to statically build the required AP bus interfaces are
>> available.
> Any ETA for those interfaces? Would be nice if we could avoid
> introducing temporary interfaces (but I'm certainly not opposing this
> patch).

I'll check with the developer.

>
>> Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com>
>> ---
>> MAINTAINERS | 1 +
>> arch/s390/include/asm/kvm-ap.h | 60 +++++++++++++++++++++++++++++
>> arch/s390/kvm/Makefile | 2 +-
>> arch/s390/kvm/kvm-ap.c | 83 ++++++++++++++++++++++++++++++++++++++++
>> arch/s390/kvm/kvm-s390.c | 42 +-------------------
>> 5 files changed, 147 insertions(+), 41 deletions(-)
>> create mode 100644 arch/s390/include/asm/kvm-ap.h
>> create mode 100644 arch/s390/kvm/kvm-ap.c
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index eab763f..224e97b 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -7792,6 +7792,7 @@ M: Christian Borntraeger <borntraeger@de.ibm.com>
>> M: Janosch Frank <frankja@linux.ibm.com>
>> R: David Hildenbrand <david@redhat.com>
>> R: Cornelia Huck <cohuck@redhat.com>
>> +R: Tony Krowiak <akrowiak@linux.vnet.ibm.com>
> Don't you want to drop the 'vnet' from your address, as the vnet-less
> form seems to be the one that will continue working from what I've
> heard?
>
>> L: linux-s390@vger.kernel.org
>> W: http://www.ibm.com/developerworks/linux/linux390/
>> T: git git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git
> No objection against this patch, although I still hope it will not be
> needed :)
>