Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "Small release overall.

  x86:
   - miscellaneous fixes
   - AVIC support (local APIC virtualization, AMD version)

  s390:
   - polling for interrupts after a VCPU goes to halted state is now
     enabled for s390
   - use hardware provided information about facility bits that do not
     need any hypervisor activity, and other fixes for cpu models and
     facilities
   - improve perf output
   - floating interrupt controller improvements.

  MIPS:
   - miscellaneous fixes

  PPC:
   - bugfixes only

  ARM:
   - 16K page size support
   - generic firmware probing layer for timer and GIC

  Christoffer Dall (KVM-ARM maintainer) says:
    "There are a few changes in this pull request touching things
     outside KVM, but they should all carry the necessary acks and it
     made the merge process much easier to do it this way."

  though actually the irqchip maintainers' acks didn't make it into the
  patches.  Marc Zyngier, who is both irqchip and KVM-ARM maintainer,
  later acked at http://mid.gmane.org/573351D1.4060303@arm.com ('more
  formally and for documentation purposes')"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (82 commits)
  KVM: MTRR: remove MSR 0x2f8
  KVM: x86: make hwapic_isr_update and hwapic_irr_update look the same
  svm: Manage vcpu load/unload when enable AVIC
  svm: Do not intercept CR8 when enable AVIC
  svm: Do not expose x2APIC when enable AVIC
  KVM: x86: Introducing kvm_x86_ops.apicv_post_state_restore
  svm: Add VMEXIT handlers for AVIC
  svm: Add interrupt injection via AVIC
  KVM: x86: Detect and Initialize AVIC support
  svm: Introduce new AVIC VMCB registers
  KVM: split kvm_vcpu_wake_up from kvm_vcpu_kick
  KVM: x86: Introducing kvm_x86_ops VCPU blocking/unblocking hooks
  KVM: x86: Introducing kvm_x86_ops VM init/destroy hooks
  KVM: x86: Rename kvm_apic_get_reg to kvm_lapic_get_reg
  KVM: x86: Misc LAPIC changes to expose helper functions
  KVM: shrink halt polling even more for invalid wakeups
  KVM: s390: set halt polling to 80 microseconds
  KVM: halt_polling: provide a way to qualify wakeups during poll
  KVM: PPC: Book3S HV: Re-enable XICS fast path for irqfd-generated interrupts
  kvm: Conditionally register IRQ bypass consumer
  ...

8 files changed, 127 insertions, 136 deletions

diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig
index 7a79b68..e5d6108 100644
--- a/virt/kvm/Kconfig
+++ b/virt/kvm/Kconfig
@@ -41,6 +41,9 @@ config KVM_VFIO
 config HAVE_KVM_ARCH_TLB_FLUSH_ALL
        bool
 
+config HAVE_KVM_INVALID_WAKEUPS
+       bool
+
 config KVM_GENERIC_DIRTYLOG_READ_PROTECT
        bool
 
diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
index 9aaa35d..409db33 100644
--- a/virt/kvm/arm/arch_timer.c
+++ b/virt/kvm/arm/arch_timer.c
@@ -17,7 +17,6 @@
  */
 
 #include <linux/cpu.h>
-#include <linux/of_irq.h>
 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
 #include <linux/interrupt.h>
@@ -438,45 +437,29 @@ static struct notifier_block kvm_timer_cpu_nb = {
 	.notifier_call = kvm_timer_cpu_notify,
 };
 
-static const struct of_device_id arch_timer_of_match[] = {
-	{ .compatible	= "arm,armv7-timer",	},
-	{ .compatible	= "arm,armv8-timer",	},
-	{},
-};
-
 int kvm_timer_hyp_init(void)
 {
-	struct device_node *np;
-	unsigned int ppi;
+	struct arch_timer_kvm_info *info;
 	int err;
 
-	timecounter = arch_timer_get_timecounter();
-	if (!timecounter)
-		return -ENODEV;
+	info = arch_timer_get_kvm_info();
+	timecounter = &info->timecounter;
 
-	np = of_find_matching_node(NULL, arch_timer_of_match);
-	if (!np) {
-		kvm_err("kvm_arch_timer: can't find DT node\n");
+	if (info->virtual_irq <= 0) {
+		kvm_err("kvm_arch_timer: invalid virtual timer IRQ: %d\n",
+			info->virtual_irq);
 		return -ENODEV;
 	}
+	host_vtimer_irq = info->virtual_irq;
 
-	ppi = irq_of_parse_and_map(np, 2);
-	if (!ppi) {
-		kvm_err("kvm_arch_timer: no virtual timer interrupt\n");
-		err = -EINVAL;
-		goto out;
-	}
-
-	err = request_percpu_irq(ppi, kvm_arch_timer_handler,
+	err = request_percpu_irq(host_vtimer_irq, kvm_arch_timer_handler,
 				 "kvm guest timer", kvm_get_running_vcpus());
 	if (err) {
 		kvm_err("kvm_arch_timer: can't request interrupt %d (%d)\n",
-			ppi, err);
+			host_vtimer_irq, err);
 		goto out;
 	}
 
-	host_vtimer_irq = ppi;
-
 	err = __register_cpu_notifier(&kvm_timer_cpu_nb);
 	if (err) {
 		kvm_err("Cannot register timer CPU notifier\n");
@@ -489,14 +472,13 @@ int kvm_timer_hyp_init(void)
 		goto out_free;
 	}
 
-	kvm_info("%s IRQ%d\n", np->name, ppi);
+	kvm_info("virtual timer IRQ%d\n", host_vtimer_irq);
 	on_each_cpu(kvm_timer_init_interrupt, NULL, 1);
 
 	goto out;
 out_free:
-	free_percpu_irq(ppi, kvm_get_running_vcpus());
+	free_percpu_irq(host_vtimer_irq, kvm_get_running_vcpus());
 out:
-	of_node_put(np);
 	return err;
 }
 
diff --git a/virt/kvm/arm/vgic-v2.c b/virt/kvm/arm/vgic-v2.c
index 67ec334..7e826c9 100644
--- a/virt/kvm/arm/vgic-v2.c
+++ b/virt/kvm/arm/vgic-v2.c
@@ -20,9 +20,6 @@
 #include <linux/kvm_host.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
-#include <linux/of_irq.h>
 
 #include <linux/irqchip/arm-gic.h>
 
@@ -186,38 +183,39 @@ static void vgic_cpu_init_lrs(void *params)
 }
 
 /**
- * vgic_v2_probe - probe for a GICv2 compatible interrupt controller in DT
- * @node:	pointer to the DT node
- * @ops: 	address of a pointer to the GICv2 operations
- * @params:	address of a pointer to HW-specific parameters
+ * vgic_v2_probe - probe for a GICv2 compatible interrupt controller
+ * @gic_kvm_info:	pointer to the GIC description
+ * @ops:		address of a pointer to the GICv2 operations
+ * @params:		address of a pointer to HW-specific parameters
  *
  * Returns 0 if a GICv2 has been found, with the low level operations
  * in *ops and the HW parameters in *params. Returns an error code
  * otherwise.
  */
-int vgic_v2_probe(struct device_node *vgic_node,
-		  const struct vgic_ops **ops,
-		  const struct vgic_params **params)
+int vgic_v2_probe(const struct gic_kvm_info *gic_kvm_info,
+		   const struct vgic_ops **ops,
+		   const struct vgic_params **params)
 {
 	int ret;
-	struct resource vctrl_res;
-	struct resource vcpu_res;
 	struct vgic_params *vgic = &vgic_v2_params;
+	const struct resource *vctrl_res = &gic_kvm_info->vctrl;
+	const struct resource *vcpu_res = &gic_kvm_info->vcpu;
 
-	vgic->maint_irq = irq_of_parse_and_map(vgic_node, 0);
-	if (!vgic->maint_irq) {
-		kvm_err("error getting vgic maintenance irq from DT\n");
+	if (!gic_kvm_info->maint_irq) {
+		kvm_err("error getting vgic maintenance irq\n");
 		ret = -ENXIO;
 		goto out;
 	}
+	vgic->maint_irq = gic_kvm_info->maint_irq;
 
-	ret = of_address_to_resource(vgic_node, 2, &vctrl_res);
-	if (ret) {
-		kvm_err("Cannot obtain GICH resource\n");
+	if (!gic_kvm_info->vctrl.start) {
+		kvm_err("GICH not present in the firmware table\n");
+		ret = -ENXIO;
 		goto out;
 	}
 
-	vgic->vctrl_base = of_iomap(vgic_node, 2);
+	vgic->vctrl_base = ioremap(gic_kvm_info->vctrl.start,
+				   resource_size(&gic_kvm_info->vctrl));
 	if (!vgic->vctrl_base) {
 		kvm_err("Cannot ioremap GICH\n");
 		ret = -ENOMEM;
@@ -228,29 +226,23 @@ int vgic_v2_probe(struct device_node *vgic_node,
 	vgic->nr_lr = (vgic->nr_lr & 0x3f) + 1;
 
 	ret = create_hyp_io_mappings(vgic->vctrl_base,
-				     vgic->vctrl_base + resource_size(&vctrl_res),
-				     vctrl_res.start);
+				     vgic->vctrl_base + resource_size(vctrl_res),
+				     vctrl_res->start);
 	if (ret) {
 		kvm_err("Cannot map VCTRL into hyp\n");
 		goto out_unmap;
 	}
 
-	if (of_address_to_resource(vgic_node, 3, &vcpu_res)) {
-		kvm_err("Cannot obtain GICV resource\n");
-		ret = -ENXIO;
-		goto out_unmap;
-	}
-
-	if (!PAGE_ALIGNED(vcpu_res.start)) {
+	if (!PAGE_ALIGNED(vcpu_res->start)) {
 		kvm_err("GICV physical address 0x%llx not page aligned\n",
-			(unsigned long long)vcpu_res.start);
+			(unsigned long long)vcpu_res->start);
 		ret = -ENXIO;
 		goto out_unmap;
 	}
 
-	if (!PAGE_ALIGNED(resource_size(&vcpu_res))) {
+	if (!PAGE_ALIGNED(resource_size(vcpu_res))) {
 		kvm_err("GICV size 0x%llx not a multiple of page size 0x%lx\n",
-			(unsigned long long)resource_size(&vcpu_res),
+			(unsigned long long)resource_size(vcpu_res),
 			PAGE_SIZE);
 		ret = -ENXIO;
 		goto out_unmap;
@@ -259,10 +251,10 @@ int vgic_v2_probe(struct device_node *vgic_node,
 	vgic->can_emulate_gicv2 = true;
 	kvm_register_device_ops(&kvm_arm_vgic_v2_ops, KVM_DEV_TYPE_ARM_VGIC_V2);
 
-	vgic->vcpu_base = vcpu_res.start;
+	vgic->vcpu_base = vcpu_res->start;
 
-	kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
-		 vctrl_res.start, vgic->maint_irq);
+	kvm_info("GICH base=0x%llx, GICV base=0x%llx, IRQ=%d\n",
+		 gic_kvm_info->vctrl.start, vgic->vcpu_base, vgic->maint_irq);
 
 	vgic->type = VGIC_V2;
 	vgic->max_gic_vcpus = VGIC_V2_MAX_CPUS;
@@ -276,6 +268,5 @@ int vgic_v2_probe(struct device_node *vgic_node,
 out_unmap:
 	iounmap(vgic->vctrl_base);
 out:
-	of_node_put(vgic_node);
 	return ret;
 }
diff --git a/virt/kvm/arm/vgic-v3.c b/virt/kvm/arm/vgic-v3.c
index 999bdc6..c02a1b1 100644
--- a/virt/kvm/arm/vgic-v3.c
+++ b/virt/kvm/arm/vgic-v3.c
@@ -20,11 +20,9 @@
 #include <linux/kvm_host.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
-#include <linux/of_irq.h>
 
 #include <linux/irqchip/arm-gic-v3.h>
+#include <linux/irqchip/arm-gic-common.h>
 
 #include <asm/kvm_emulate.h>
 #include <asm/kvm_arm.h>
@@ -222,30 +220,24 @@ static void vgic_cpu_init_lrs(void *params)
 }
 
 /**
- * vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
- * @node:	pointer to the DT node
- * @ops: 	address of a pointer to the GICv3 operations
- * @params:	address of a pointer to HW-specific parameters
+ * vgic_v3_probe - probe for a GICv3 compatible interrupt controller
+ * @gic_kvm_info:	pointer to the GIC description
+ * @ops:		address of a pointer to the GICv3 operations
+ * @params:		address of a pointer to HW-specific parameters
  *
  * Returns 0 if a GICv3 has been found, with the low level operations
  * in *ops and the HW parameters in *params. Returns an error code
  * otherwise.
  */
-int vgic_v3_probe(struct device_node *vgic_node,
+int vgic_v3_probe(const struct gic_kvm_info *gic_kvm_info,
 		  const struct vgic_ops **ops,
 		  const struct vgic_params **params)
 {
 	int ret = 0;
-	u32 gicv_idx;
-	struct resource vcpu_res;
 	struct vgic_params *vgic = &vgic_v3_params;
+	const struct resource *vcpu_res = &gic_kvm_info->vcpu;
 
-	vgic->maint_irq = irq_of_parse_and_map(vgic_node, 0);
-	if (!vgic->maint_irq) {
-		kvm_err("error getting vgic maintenance irq from DT\n");
-		ret = -ENXIO;
-		goto out;
-	}
+	vgic->maint_irq = gic_kvm_info->maint_irq;
 
 	ich_vtr_el2 = kvm_call_hyp(__vgic_v3_get_ich_vtr_el2);
 
@@ -256,24 +248,19 @@ int vgic_v3_probe(struct device_node *vgic_node,
 	vgic->nr_lr = (ich_vtr_el2 & 0xf) + 1;
 	vgic->can_emulate_gicv2 = false;
 
-	if (of_property_read_u32(vgic_node, "#redistributor-regions", &gicv_idx))
-		gicv_idx = 1;
-
-	gicv_idx += 3; /* Also skip GICD, GICC, GICH */
-	if (of_address_to_resource(vgic_node, gicv_idx, &vcpu_res)) {
+	if (!vcpu_res->start) {
 		kvm_info("GICv3: no GICV resource entry\n");
 		vgic->vcpu_base = 0;
-	} else if (!PAGE_ALIGNED(vcpu_res.start)) {
+	} else if (!PAGE_ALIGNED(vcpu_res->start)) {
 		pr_warn("GICV physical address 0x%llx not page aligned\n",
-			(unsigned long long)vcpu_res.start);
+			(unsigned long long)vcpu_res->start);
 		vgic->vcpu_base = 0;
-	} else if (!PAGE_ALIGNED(resource_size(&vcpu_res))) {
+	} else if (!PAGE_ALIGNED(resource_size(vcpu_res))) {
 		pr_warn("GICV size 0x%llx not a multiple of page size 0x%lx\n",
-			(unsigned long long)resource_size(&vcpu_res),
+			(unsigned long long)resource_size(vcpu_res),
 			PAGE_SIZE);
-		vgic->vcpu_base = 0;
 	} else {
-		vgic->vcpu_base = vcpu_res.start;
+		vgic->vcpu_base = vcpu_res->start;
 		vgic->can_emulate_gicv2 = true;
 		kvm_register_device_ops(&kvm_arm_vgic_v2_ops,
 					KVM_DEV_TYPE_ARM_VGIC_V2);
@@ -286,15 +273,13 @@ int vgic_v3_probe(struct device_node *vgic_node,
 	vgic->type = VGIC_V3;
 	vgic->max_gic_vcpus = VGIC_V3_MAX_CPUS;
 
-	kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
-		 vcpu_res.start, vgic->maint_irq);
+	kvm_info("GICV base=0x%llx, IRQ=%d\n",
+		 vgic->vcpu_base, vgic->maint_irq);
 
 	on_each_cpu(vgic_cpu_init_lrs, vgic, 1);
 
 	*ops = &vgic_v3_ops;
 	*params = vgic;
 
-out:
-	of_node_put(vgic_node);
 	return ret;
 }
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 00429b3..60668a7 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -21,9 +21,7 @@
 #include <linux/kvm_host.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
-#include <linux/of_irq.h>
+#include <linux/irq.h>
 #include <linux/rculist.h>
 #include <linux/uaccess.h>
 
@@ -33,6 +31,7 @@
 #include <trace/events/kvm.h>
 #include <asm/kvm.h>
 #include <kvm/iodev.h>
+#include <linux/irqchip/arm-gic-common.h>
 
 #define CREATE_TRACE_POINTS
 #include "trace.h"
@@ -2389,33 +2388,38 @@ static struct notifier_block vgic_cpu_nb = {
 	.notifier_call = vgic_cpu_notify,
 };
 
-static const struct of_device_id vgic_ids[] = {
-	{ .compatible = "arm,cortex-a15-gic",	.data = vgic_v2_probe, },
-	{ .compatible = "arm,cortex-a7-gic",	.data = vgic_v2_probe, },
-	{ .compatible = "arm,gic-400",		.data = vgic_v2_probe, },
-	{ .compatible = "arm,gic-v3",		.data = vgic_v3_probe, },
-	{},
-};
-
-int kvm_vgic_hyp_init(void)
+static int kvm_vgic_probe(void)
 {
-	const struct of_device_id *matched_id;
-	const int (*vgic_probe)(struct device_node *,const struct vgic_ops **,
-				const struct vgic_params **);
-	struct device_node *vgic_node;
+	const struct gic_kvm_info *gic_kvm_info;
 	int ret;
 
-	vgic_node = of_find_matching_node_and_match(NULL,
-						    vgic_ids, &matched_id);
-	if (!vgic_node) {
-		kvm_err("error: no compatible GIC node found\n");
+	gic_kvm_info = gic_get_kvm_info();
+	if (!gic_kvm_info)
 		return -ENODEV;
+
+	switch (gic_kvm_info->type) {
+	case GIC_V2:
+		ret = vgic_v2_probe(gic_kvm_info, &vgic_ops, &vgic);
+		break;
+	case GIC_V3:
+		ret = vgic_v3_probe(gic_kvm_info, &vgic_ops, &vgic);
+		break;
+	default:
+		ret = -ENODEV;
 	}
 
-	vgic_probe = matched_id->data;
-	ret = vgic_probe(vgic_node, &vgic_ops, &vgic);
-	if (ret)
+	return ret;
+}
+
+int kvm_vgic_hyp_init(void)
+{
+	int ret;
+
+	ret = kvm_vgic_probe();
+	if (ret) {
+		kvm_err("error: KVM vGIC probing failed\n");
 		return ret;
+	}
 
 	ret = request_percpu_irq(vgic->maint_irq, vgic_maintenance_handler,
 				 "vgic", kvm_get_running_vcpus());
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index 46dbc0a..e469b60 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -408,15 +408,17 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args)
 	 */
 	fdput(f);
 #ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
-	irqfd->consumer.token = (void *)irqfd->eventfd;
-	irqfd->consumer.add_producer = kvm_arch_irq_bypass_add_producer;
-	irqfd->consumer.del_producer = kvm_arch_irq_bypass_del_producer;
-	irqfd->consumer.stop = kvm_arch_irq_bypass_stop;
-	irqfd->consumer.start = kvm_arch_irq_bypass_start;
-	ret = irq_bypass_register_consumer(&irqfd->consumer);
-	if (ret)
-		pr_info("irq bypass consumer (token %p) registration fails: %d\n",
+	if (kvm_arch_has_irq_bypass()) {
+		irqfd->consumer.token = (void *)irqfd->eventfd;
+		irqfd->consumer.add_producer = kvm_arch_irq_bypass_add_producer;
+		irqfd->consumer.del_producer = kvm_arch_irq_bypass_del_producer;
+		irqfd->consumer.stop = kvm_arch_irq_bypass_stop;
+		irqfd->consumer.start = kvm_arch_irq_bypass_start;
+		ret = irq_bypass_register_consumer(&irqfd->consumer);
+		if (ret)
+			pr_info("irq bypass consumer (token %p) registration fails: %d\n",
 				irqfd->consumer.token, ret);
+	}
 #endif
 
 	return 0;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 4fd482f..dd4ac9d 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2028,6 +2028,8 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu)
 			 */
 			if (kvm_vcpu_check_block(vcpu) < 0) {
 				++vcpu->stat.halt_successful_poll;
+				if (!vcpu_valid_wakeup(vcpu))
+					++vcpu->stat.halt_poll_invalid;
 				goto out;
 			}
 			cur = ktime_get();
@@ -2053,7 +2055,9 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu)
 out:
 	block_ns = ktime_to_ns(cur) - ktime_to_ns(start);
 
-	if (halt_poll_ns) {
+	if (!vcpu_valid_wakeup(vcpu))
+		shrink_halt_poll_ns(vcpu);
+	else if (halt_poll_ns) {
 		if (block_ns <= vcpu->halt_poll_ns)
 			;
 		/* we had a long block, shrink polling */
@@ -2066,18 +2070,14 @@ out:
 	} else
 		vcpu->halt_poll_ns = 0;
 
-	trace_kvm_vcpu_wakeup(block_ns, waited);
+	trace_kvm_vcpu_wakeup(block_ns, waited, vcpu_valid_wakeup(vcpu));
+	kvm_arch_vcpu_block_finish(vcpu);
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_block);
 
 #ifndef CONFIG_S390
-/*
- * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
- */
-void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
+void kvm_vcpu_wake_up(struct kvm_vcpu *vcpu)
 {
-	int me;
-	int cpu = vcpu->cpu;
 	struct swait_queue_head *wqp;
 
 	wqp = kvm_arch_vcpu_wq(vcpu);
@@ -2086,6 +2086,18 @@ void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
 		++vcpu->stat.halt_wakeup;
 	}
 
+}
+EXPORT_SYMBOL_GPL(kvm_vcpu_wake_up);
+
+/*
+ * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
+ */
+void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
+{
+	int me;
+	int cpu = vcpu->cpu;
+
+	kvm_vcpu_wake_up(vcpu);
 	me = get_cpu();
 	if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
 		if (kvm_arch_vcpu_should_kick(vcpu))
@@ -2272,7 +2284,7 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
 	int r;
 	struct kvm_vcpu *vcpu;
 
-	if (id >= KVM_MAX_VCPUS)
+	if (id >= KVM_MAX_VCPU_ID)
 		return -EINVAL;
 
 	vcpu = kvm_arch_vcpu_create(kvm, id);
@@ -2746,6 +2758,8 @@ static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
 	case KVM_CAP_MULTI_ADDRESS_SPACE:
 		return KVM_ADDRESS_SPACE_NUM;
 #endif
+	case KVM_CAP_MAX_VCPU_ID:
+		return KVM_MAX_VCPU_ID;
 	default:
 		break;
 	}
diff --git a/virt/lib/irqbypass.c b/virt/lib/irqbypass.c
index 09a03b5..52abac4 100644
--- a/virt/lib/irqbypass.c
+++ b/virt/lib/irqbypass.c
@@ -89,6 +89,9 @@ int irq_bypass_register_producer(struct irq_bypass_producer *producer)
 	struct irq_bypass_producer *tmp;
 	struct irq_bypass_consumer *consumer;
 
+	if (!producer->token)
+		return -EINVAL;
+
 	might_sleep();
 
 	if (!try_module_get(THIS_MODULE))
@@ -136,6 +139,9 @@ void irq_bypass_unregister_producer(struct irq_bypass_producer *producer)
 	struct irq_bypass_producer *tmp;
 	struct irq_bypass_consumer *consumer;
 
+	if (!producer->token)
+		return;
+
 	might_sleep();
 
 	if (!try_module_get(THIS_MODULE))
@@ -177,7 +183,8 @@ int irq_bypass_register_consumer(struct irq_bypass_consumer *consumer)
 	struct irq_bypass_consumer *tmp;
 	struct irq_bypass_producer *producer;
 
-	if (!consumer->add_producer || !consumer->del_producer)
+	if (!consumer->token ||
+	    !consumer->add_producer || !consumer->del_producer)
 		return -EINVAL;
 
 	might_sleep();
@@ -227,6 +234,9 @@ void irq_bypass_unregister_consumer(struct irq_bypass_consumer *consumer)
 	struct irq_bypass_consumer *tmp;
 	struct irq_bypass_producer *producer;
 
+	if (!consumer->token)
+		return;
+
 	might_sleep();
 
 	if (!try_module_get(THIS_MODULE))