[PATCH 37/67] KVM: Don't WARN if updating IRQ bypass route fails

[Sean Christopherson]

Don't bother WARNing if updating an IRTE route fails now that vendor code
provides much more precise WARNs.  The generic WARN doesn't provide enough
information to actually debug the problem, and has obviously done nothing
to surface the myriad bugs in KVM's implementation.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
 arch/x86/kvm/x86.c       |  8 ++++----
 include/linux/kvm_host.h |  6 +++---
 virt/kvm/eventfd.c       | 15 ++++++---------
 3 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a20d461718cc..c2c102f23fa7 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -13666,11 +13666,11 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
 	kvm_arch_end_assignment(irqfd->kvm);
 }
 
-int kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd *irqfd,
-				  struct kvm_kernel_irq_routing_entry *old,
-				  struct kvm_kernel_irq_routing_entry *new)
+void kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd *irqfd,
+				   struct kvm_kernel_irq_routing_entry *old,
+				   struct kvm_kernel_irq_routing_entry *new)
 {
-	return kvm_pi_update_irte(irqfd, old, new);
+	kvm_pi_update_irte(irqfd, old, new);
 }
 
 bool kvm_arch_irqfd_route_changed(struct kvm_kernel_irq_routing_entry *old,
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 2d9f3aeb766a..7e8f5cb4fc9a 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -2392,9 +2392,9 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *,
 			   struct irq_bypass_producer *);
 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *);
 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *);
-int kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd *irqfd,
-				  struct kvm_kernel_irq_routing_entry *old,
-				  struct kvm_kernel_irq_routing_entry *new);
+void kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd *irqfd,
+				   struct kvm_kernel_irq_routing_entry *old,
+				   struct kvm_kernel_irq_routing_entry *new);
 bool kvm_arch_irqfd_route_changed(struct kvm_kernel_irq_routing_entry *,
 				  struct kvm_kernel_irq_routing_entry *);
 #endif /* CONFIG_HAVE_KVM_IRQ_BYPASS */
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index ad71e3e4d1c3..7ccdaa4071c8 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -285,11 +285,11 @@ void __attribute__((weak)) kvm_arch_irq_bypass_start(
 {
 }
 
-int __weak kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd *irqfd,
-					 struct kvm_kernel_irq_routing_entry *old,
-					 struct kvm_kernel_irq_routing_entry *new)
+void __weak kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd *irqfd,
+					  struct kvm_kernel_irq_routing_entry *old,
+					  struct kvm_kernel_irq_routing_entry *new)
 {
-	return 0;
+
 }
 
 bool __attribute__((weak)) kvm_arch_irqfd_route_changed(
@@ -618,11 +618,8 @@ void kvm_irq_routing_update(struct kvm *kvm)
 
 #ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
 		if (irqfd->producer &&
-		    kvm_arch_irqfd_route_changed(&old, &irqfd->irq_entry)) {
-			int ret = kvm_arch_update_irqfd_routing(irqfd, &old, &irqfd->irq_entry);
-
-			WARN_ON(ret);
-		}
+		    kvm_arch_irqfd_route_changed(&old, &irqfd->irq_entry))
+			kvm_arch_update_irqfd_routing(irqfd, &old, &irqfd->irq_entry);
 #endif
 	}
 
-- 
2.49.0.504.g3bcea36a83-goog