From 85a19b3054274e09bcd9043d7d3203c3836688d0 Mon Sep 17 00:00:00 2001 From: Eric Farman Date: Mon, 5 Feb 2024 22:43:00 +0100 Subject: KVM: s390: only deliver the set service event bits The SCLP driver code masks off the last two bits of the parameter [1] to determine if a read is required, but doesn't care about the contents of those bits. Meanwhile, the KVM code that delivers event interrupts masks off those two bits but sends both to the guest, even if only one was specified by userspace [2]. This works for the driver code, but it means any nuances of those bits gets lost. Use the event pending mask as an actual mask, and only send the bit(s) that were specified in the pending interrupt. [1] Linux: sclp_interrupt_handler() (drivers/s390/char/sclp.c:658) [2] QEMU: service_interrupt() (hw/s390x/sclp.c:360..363) Fixes: 0890ddea1a90 ("KVM: s390: protvirt: Add SCLP interrupt handling") Signed-off-by: Eric Farman Reviewed-by: Christian Borntraeger Reviewed-by: Janosch Frank Link: https://lore.kernel.org/r/20240205214300.1018522-1-farman@linux.ibm.com Signed-off-by: Janosch Frank Message-Id: <20240205214300.1018522-1-farman@linux.ibm.com> --- arch/s390/kvm/interrupt.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index fc4007cc067a..20e080e9150b 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -1031,7 +1031,7 @@ static int __must_check __deliver_service_ev(struct kvm_vcpu *vcpu) return 0; } ext = fi->srv_signal; - /* only clear the event bit */ + /* only clear the event bits */ fi->srv_signal.ext_params &= ~SCCB_EVENT_PENDING; clear_bit(IRQ_PEND_EXT_SERVICE_EV, &fi->pending_irqs); spin_unlock(&fi->lock); @@ -1041,7 +1041,7 @@ static int __must_check __deliver_service_ev(struct kvm_vcpu *vcpu) trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_INT_SERVICE, ext.ext_params, 0); - return write_sclp(vcpu, SCCB_EVENT_PENDING); + return write_sclp(vcpu, ext.ext_params & SCCB_EVENT_PENDING); } static int __must_check __deliver_pfault_done(struct kvm_vcpu *vcpu) -- cgit v1.2.3