4.15-stable review patch. If anyone has any objections, please let me know.
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From: David Hildenbrand david@redhat.com
commit 5fe01793dd953ab947fababe8abaf5ed5258c8df upstream.
Missed when enabling the Multiple-epoch facility. If the facility is installed and the control is set, a sign based comaprison has to be performed.
Right now we would inject wrong interrupts and ignore interrupt conditions. Also the sleep time is calculated in a wrong way.
Signed-off-by: David Hildenbrand david@redhat.com Message-Id: 20180207114647.6220-2-david@redhat.com Fixes: 8fa1696ea781 ("KVM: s390: Multiple Epoch Facility support") Cc: stable@vger.kernel.org Reviewed-by: Christian Borntraeger borntraeger@de.ibm.com Signed-off-by: Christian Borntraeger borntraeger@de.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/s390/kvm/interrupt.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-)
--- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -170,8 +170,15 @@ static int ckc_interrupts_enabled(struct
static int ckc_irq_pending(struct kvm_vcpu *vcpu) { - if (vcpu->arch.sie_block->ckc >= kvm_s390_get_tod_clock_fast(vcpu->kvm)) + const u64 now = kvm_s390_get_tod_clock_fast(vcpu->kvm); + const u64 ckc = vcpu->arch.sie_block->ckc; + + if (vcpu->arch.sie_block->gcr[0] & 0x0020000000000000ul) { + if ((s64)ckc >= (s64)now) + return 0; + } else if (ckc >= now) { return 0; + } return ckc_interrupts_enabled(vcpu); }
@@ -1011,13 +1018,19 @@ int kvm_cpu_has_pending_timer(struct kvm
static u64 __calculate_sltime(struct kvm_vcpu *vcpu) { - u64 now, cputm, sltime = 0; + const u64 now = kvm_s390_get_tod_clock_fast(vcpu->kvm); + const u64 ckc = vcpu->arch.sie_block->ckc; + u64 cputm, sltime = 0;
if (ckc_interrupts_enabled(vcpu)) { - now = kvm_s390_get_tod_clock_fast(vcpu->kvm); - sltime = tod_to_ns(vcpu->arch.sie_block->ckc - now); - /* already expired or overflow? */ - if (!sltime || vcpu->arch.sie_block->ckc <= now) + if (vcpu->arch.sie_block->gcr[0] & 0x0020000000000000ul) { + if ((s64)now < (s64)ckc) + sltime = tod_to_ns((s64)ckc - (s64)now); + } else if (now < ckc) { + sltime = tod_to_ns(ckc - now); + } + /* already expired */ + if (!sltime) return 0; if (cpu_timer_interrupts_enabled(vcpu)) { cputm = kvm_s390_get_cpu_timer(vcpu);