From 3fd8417f2c728d810a3b26d7e2008012ffb7fd01 Mon Sep 17 00:00:00 2001 From: Collin Walling Date: Tue, 26 Oct 2021 22:54:51 -0400 Subject: [PATCH] KVM: s390: add debug statement for diag 318 CPNC data The diag 318 data contains values that denote information regarding the guest's environment. Currently, it is unecessarily difficult to observe this value (either manually-inserted debug statements, gdb stepping, mem dumping etc). It's useful to observe this information to obtain an at-a-glance view of the guest's environment, so lets add a simple VCPU event that prints the CPNC to the s390dbf logs. Signed-off-by: Collin Walling Acked-by: Christian Borntraeger Link: https://lore.kernel.org/r/20211027025451.290124-1-walling@linux.ibm.com [borntraeger@de.ibm.com]: change debug level to 3 Signed-off-by: Christian Borntraeger --- arch/s390/kvm/kvm-s390.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 6482ea9139bb4..c6257f625929c 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -4255,6 +4255,7 @@ static void sync_regs_fmt2(struct kvm_vcpu *vcpu) if (kvm_run->kvm_dirty_regs & KVM_SYNC_DIAG318) { vcpu->arch.diag318_info.val = kvm_run->s.regs.diag318; vcpu->arch.sie_block->cpnc = vcpu->arch.diag318_info.cpnc; + VCPU_EVENT(vcpu, 3, "setting cpnc to %d", vcpu->arch.diag318_info.cpnc); } /* * If userspace sets the riccb (e.g. after migration) to a valid state, -- 2.30.2