From ef1535901a07f2e49fa25c8bcee7f0b73801d824 Mon Sep 17 00:00:00 2001
From: Janosch Frank <frankja@linux.ibm.com>
Date: Fri, 1 Sep 2023 11:48:51 +0000
Subject: [PATCH] s390x: do a subsystem reset before the unprotect on reboot
Bound APQNs have to be reset before tearing down the secure config via
s390_machine_unprotect(). Otherwise the Ultravisor will return a error
code.
So let's do a subsystem_reset() which includes a AP reset before the
unprotect call. We'll do a full device_reset() afterwards which will
reset some devices twice. That's ok since we can't move the
device_reset() before the unprotect as it includes a CPU clear reset
which the Ultravisor does not expect at that point in time.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Message-ID: <20230901114851.154357-1-frankja@linux.ibm.com>
Tested-by: Viktor Mihajlovski <mihajlov@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
hw/s390x/s390-virtio-ccw.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index 3dd0b2372d..2d75f2131f 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -438,10 +438,20 @@ static void s390_machine_reset(MachineState *machine, ShutdownCause reason)
switch (reset_type) {
case S390_RESET_EXTERNAL:
case S390_RESET_REIPL:
+ /*
+ * Reset the subsystem which includes a AP reset. If a PV
+ * guest had APQNs attached the AP reset is a prerequisite to
+ * unprotecting since the UV checks if all APQNs are reset.
+ */
+ subsystem_reset();
if (s390_is_pv()) {
s390_machine_unprotect(ms);
}
+ /*
+ * Device reset includes CPU clear resets so this has to be
+ * done AFTER the unprotect call above.
+ */
qemu_devices_reset(reason);
s390_crypto_reset();
--
2.30.2