On 01.04.19 23:48, Collin Walling wrote:
DIAGNOSE 0x318 (diag318) is a privileged s390x instruction that must
be intercepted by SIE and handled via KVM. Let's introduce some
functions to communicate between QEMU and KVM via ioctls. These
will be used to get/set the diag318 related information (also known
as the "Control Program Code" or "CPC"), as well as check the system
if KVM supports handling this instruction.
Diag318 must also be reset on a load normal and modified clear, so
we use the set function (wrapped in a reset function) to explicitly
set the diag318 info to 0 for these cases.
Lastly, we want to ensure the diag318 info is migrated. The diag318
info migration is handled via a VMStateDescription. This feature is
only supported on QEMU machines 4.0 and later.
This has to become 4.1
Signed-off-by: Collin Walling <address@hidden>
---
This version is posted in tandem with a new kernel patch that changes
how the execution of the diag 0x318 instruction is handled. A link to
this series will be attached as a reply to this series for convenience.
Changelog:
v3
- removed CPU model code
- removed RSCPI and SCLP code
- reverted max cpus back to 248 (previous patches limited this
to 247)
- introduced VMStateDescription handlers for migration
- disabled migration of diag318 info for machines 3.1 and older
- a warning is printed if migration is disabled and KVM
supports handling this instruction
---
hw/s390x/s390-virtio-ccw.c | 6 ++++
linux-headers/asm-s390/kvm.h | 4 +++
target/s390x/diag.c | 63 ++++++++++++++++++++++++++++++++++++
target/s390x/internal.h | 5 ++-
target/s390x/kvm-stub.c | 15 +++++++++
target/s390x/kvm.c | 32 ++++++++++++++++++
target/s390x/kvm_s390x.h | 3 ++
7 files changed, 127 insertions(+), 1 deletion(-)
diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index d11069b860..2a50868496 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -36,6 +36,7 @@
#include "cpu_models.h"
#include "hw/nmi.h"
#include "hw/s390x/tod.h"
+#include "internal.h"
S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
{
@@ -302,6 +303,8 @@ static void ccw_init(MachineState *machine)
/* init the TOD clock */
s390_init_tod();
+
+ diag318_register_migration();
}
static void s390_cpu_plug(HotplugHandler *hotplug_dev,
@@ -352,6 +355,7 @@ static void s390_machine_reset(void)
}
subsystem_reset();
s390_crypto_reset();
+ diag318_reset();
Shouldn't this go into subsystem_reset?
Aren't you missing resets during external/reipl resets?
Also, I was wondering if this would be worth creating a fake device like
diag288. The resets can be handled similar to diag288. Resets during
external/reipl reset would come natural.