[PATCH v2 00/18] KVM: x86: Add I/O APIC kconfig, delete irq_comm.c

[PATCH v2 00/18] KVM: x86: Add I/O APIC kconfig, delete irq_comm.c

[Sean Christopherson]

Add CONFIG_KVM_IOAPIC to allow disabling support for KVM's I/O APIC (and PIC
and PIT) emulation, and delete irq_comm.c by moving its contents to other
files.

Vitaly and Kai, I didn't apply your review/ack to the Hyper-V patch, as I ended
up keeping the helper as kvm_hv_synic_set_irq() to fix the tracepoint
inconsistency and the bad changelog.

v2:
 - Keep kvm_hv_synic_set_irq() instead of renaming it kvm_hv_set_sint() to
   stay consistent with kvm_pic_set_irq() and kvm_ioapic_set_irq(), and with
   its tracepoint. [Vitaly, Kai]
 - Keep kvm_setup_default_irq_routine() instead of folding it into I/O APIC
   allocation, but rename it to kvm_setup_default_ioapic_and_pic_routing().
   [Paolo].
 - Move a bit more code out of x86.c (this time into i8254.c).
 - Guard more code with CONFIG_KVM_IOAPIC (e.g. struct kvm_pit).
 - Fix a changelog typo. [Kai]
 - Collect Kai's Acked-by. [Kai]

v1: https://lore.kernel.org/all/20250519232808.2745331-1-seanjc@google.com

Sean Christopherson (18):
  KVM: x86: Trigger I/O APIC route rescan in
    kvm_arch_irq_routing_update()
  KVM: x86: Drop superfluous kvm_set_pic_irq() => kvm_pic_set_irq()
    wrapper
  KVM: x86: Drop superfluous kvm_set_ioapic_irq() =>
    kvm_ioapic_set_irq() wrapper
  KVM: x86: Drop superfluous kvm_hv_set_sint() => kvm_hv_synic_set_irq()
    wrapper
  KVM: x86: Move PIT ioctl helpers to i8254.c
  KVM: x86: Move KVM_{GET,SET}_IRQCHIP ioctl helpers to irq.c
  KVM: x86: Rename irqchip_kernel() to irqchip_full()
  KVM: x86: Move kvm_setup_default_irq_routing() into irq.c
  KVM: x86: Move kvm_{request,free}_irq_source_id() to i8254.c (PIT)
  KVM: x86: Hardcode the PIT IRQ source ID to '2'
  KVM: x86: Don't clear PIT's IRQ line status when destroying PIT
  KVM: x86: Explicitly check for in-kernel PIC when getting ExtINT
  KVM: Move x86-only tracepoints to x86's trace.h
  KVM: x86: Add CONFIG_KVM_IOAPIC to allow disabling in-kernel I/O APIC
  KVM: Squash two CONFIG_HAVE_KVM_IRQCHIP #ifdefs into one
  KVM: selftests: Fall back to split IRQ chip if full in-kernel chip is
    unsupported
  KVM: x86: Move IRQ mask notifier infrastructure to I/O APIC emulation
  KVM: x86: Fold irq_comm.c into irq.c

 arch/x86/include/asm/kvm_host.h            |  22 +-
 arch/x86/kvm/Kconfig                       |  10 +
 arch/x86/kvm/Makefile                      |   7 +-
 arch/x86/kvm/hyperv.c                      |  10 +-
 arch/x86/kvm/hyperv.h                      |   3 +-
 arch/x86/kvm/i8254.c                       |  90 +++-
 arch/x86/kvm/i8254.h                       |  17 +-
 arch/x86/kvm/i8259.c                       |  17 +-
 arch/x86/kvm/ioapic.c                      |  55 ++-
 arch/x86/kvm/ioapic.h                      |  24 +-
 arch/x86/kvm/irq.c                         | 427 ++++++++++++++++++-
 arch/x86/kvm/irq.h                         |  35 +-
 arch/x86/kvm/irq_comm.c                    | 469 ---------------------
 arch/x86/kvm/lapic.c                       |   7 +-
 arch/x86/kvm/trace.h                       |  80 ++++
 arch/x86/kvm/x86.c                         | 164 +------
 include/linux/kvm_host.h                   |   9 +-
 include/trace/events/kvm.h                 |  84 +---
 tools/testing/selftests/kvm/lib/kvm_util.c |  13 +-
 virt/kvm/irqchip.c                         |   2 -
 20 files changed, 746 insertions(+), 799 deletions(-)
 delete mode 100644 arch/x86/kvm/irq_comm.c


base-commit: 61374cc145f4a56377eaf87c7409a97ec7a34041
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 01/18] KVM: x86: Trigger I/O APIC route rescan in kvm_arch_irq_routing_update()

[Sean Christopherson]

Trigger the I/O APIC route rescan that's performed for a split IRQ chip
after userspace updates IRQ routes in kvm_arch_irq_routing_update(), i.e.
before dropping kvm->irq_lock.  Calling kvm_make_all_cpus_request() under
a mutex is perfectly safe, and the smp_wmb()+smp_mb__after_atomic() pair
in __kvm_make_request()+kvm_check_request() ensures the new routing is
visible to vCPUs prior to the request being visible to vCPUs.

In all likelihood, commit b053b2aef25d ("KVM: x86: Add EOI exit bitmap
inference") somewhat arbitrarily made the request outside of irq_lock to
avoid holding irq_lock any longer than is strictly necessary.  And then
commit abdb080f7ac8 ("kvm/irqchip: kvm_arch_irq_routing_update renaming
split") took the easy route of adding another arch hook instead of risking
a functional change.

Note, the call to synchronize_srcu_expedited() does NOT provide ordering
guarantees with respect to vCPUs scanning the new routing; as above, the
request infrastructure provides the necessary ordering.  I.e. there's no
need to wait for kvm_scan_ioapic_routes() to complete if it's actively
running, because regardless of whether it grabs the old or new table, the
vCPU will have another KVM_REQ_SCAN_IOAPIC pending, i.e. will rescan again
and see the new mappings.

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/irq_comm.c  | 10 +++-------
 include/linux/kvm_host.h |  4 ----
 virt/kvm/irqchip.c       |  2 --
 3 files changed, 3 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index d6d792b5d1bd..e2ae62ff9cc2 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -395,13 +395,6 @@ int kvm_setup_default_irq_routing(struct kvm *kvm)
 				   ARRAY_SIZE(default_routing), 0);
 }
 
-void kvm_arch_post_irq_routing_update(struct kvm *kvm)
-{
-	if (!irqchip_split(kvm))
-		return;
-	kvm_make_scan_ioapic_request(kvm);
-}
-
 void kvm_scan_ioapic_irq(struct kvm_vcpu *vcpu, u32 dest_id, u16 dest_mode,
 			 u8 vector, unsigned long *ioapic_handled_vectors)
 {
@@ -466,4 +459,7 @@ void kvm_arch_irq_routing_update(struct kvm *kvm)
 #ifdef CONFIG_KVM_HYPERV
 	kvm_hv_irq_routing_update(kvm);
 #endif
+
+	if (irqchip_split(kvm))
+		kvm_make_scan_ioapic_request(kvm);
 }
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 3bde4fb5c6aa..9461517b4e62 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1024,14 +1024,10 @@ void vcpu_put(struct kvm_vcpu *vcpu);
 
 #ifdef __KVM_HAVE_IOAPIC
 void kvm_arch_post_irq_ack_notifier_list_update(struct kvm *kvm);
-void kvm_arch_post_irq_routing_update(struct kvm *kvm);
 #else
 static inline void kvm_arch_post_irq_ack_notifier_list_update(struct kvm *kvm)
 {
 }
-static inline void kvm_arch_post_irq_routing_update(struct kvm *kvm)
-{
-}
 #endif
 
 #ifdef CONFIG_HAVE_KVM_IRQCHIP
diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c
index 162d8ed889f2..6ccabfd32287 100644
--- a/virt/kvm/irqchip.c
+++ b/virt/kvm/irqchip.c
@@ -222,8 +222,6 @@ int kvm_set_irq_routing(struct kvm *kvm,
 	kvm_arch_irq_routing_update(kvm);
 	mutex_unlock(&kvm->irq_lock);
 
-	kvm_arch_post_irq_routing_update(kvm);
-
 	synchronize_srcu_expedited(&kvm->irq_srcu);
 
 	new = old;
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 02/18] KVM: x86: Drop superfluous kvm_set_pic_irq() => kvm_pic_set_irq() wrapper

[Sean Christopherson]

Drop the superfluous and confusing kvm_set_pic_irq() => kvm_pic_set_irq()
wrapper, and instead wire up ->set() directly to its final destination.

Opportunistically move the declaration kvm_pic_set_irq() to irq.h to
start gathering more of the in-kernel APIC/IO-APIC logic in irq.{c,h}.

No functional change intended.

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/include/asm/kvm_host.h |  1 -
 arch/x86/kvm/i8259.c            |  5 ++++-
 arch/x86/kvm/irq.h              |  2 ++
 arch/x86/kvm/irq_comm.c         | 10 +---------
 4 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 330cdcbed1a6..f25ec3ec5ce4 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -2208,7 +2208,6 @@ static inline int __kvm_irq_line_state(unsigned long *irq_state,
 	return !!(*irq_state);
 }
 
-int kvm_pic_set_irq(struct kvm_pic *pic, int irq, int irq_source_id, int level);
 void kvm_pic_clear_all(struct kvm_pic *pic, int irq_source_id);
 
 void kvm_inject_nmi(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index a8fb19940975..0150aec4f523 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -185,8 +185,11 @@ void kvm_pic_update_irq(struct kvm_pic *s)
 	pic_unlock(s);
 }
 
-int kvm_pic_set_irq(struct kvm_pic *s, int irq, int irq_source_id, int level)
+int kvm_pic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
+		    int irq_source_id, int level, bool line_status)
 {
+	struct kvm_pic *s = kvm->arch.vpic;
+	int irq = e->irqchip.pin;
 	int ret, irq_level;
 
 	BUG_ON(irq < 0 || irq >= PIC_NUM_PINS);
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 76d46b2f41dd..33dd5666b656 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -63,6 +63,8 @@ int kvm_pic_init(struct kvm *kvm);
 void kvm_pic_destroy(struct kvm *kvm);
 int kvm_pic_read_irq(struct kvm *kvm);
 void kvm_pic_update_irq(struct kvm_pic *s);
+int kvm_pic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
+		    int irq_source_id, int level, bool line_status);
 
 static inline int irqchip_split(struct kvm *kvm)
 {
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index e2ae62ff9cc2..64f352e7bcb0 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -27,14 +27,6 @@
 #include "x86.h"
 #include "xen.h"
 
-static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
-			   struct kvm *kvm, int irq_source_id, int level,
-			   bool line_status)
-{
-	struct kvm_pic *pic = kvm->arch.vpic;
-	return kvm_pic_set_irq(pic, e->irqchip.pin, irq_source_id, level);
-}
-
 static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
 			      struct kvm *kvm, int irq_source_id, int level,
 			      bool line_status)
@@ -296,7 +288,7 @@ int kvm_set_routing_entry(struct kvm *kvm,
 		case KVM_IRQCHIP_PIC_MASTER:
 			if (ue->u.irqchip.pin >= PIC_NUM_PINS / 2)
 				return -EINVAL;
-			e->set = kvm_set_pic_irq;
+			e->set = kvm_pic_set_irq;
 			break;
 		case KVM_IRQCHIP_IOAPIC:
 			if (ue->u.irqchip.pin >= KVM_IOAPIC_NUM_PINS)
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 03/18] KVM: x86: Drop superfluous kvm_set_ioapic_irq() => kvm_ioapic_set_irq() wrapper

[Sean Christopherson]

Drop the superfluous and confusing kvm_set_ioapic_irq() and instead wire
up ->set() directly to its final destination.

No functional change intended.

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/ioapic.c   |  6 ++++--
 arch/x86/kvm/ioapic.h   |  5 +++--
 arch/x86/kvm/irq_comm.c | 11 +----------
 3 files changed, 8 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index 45dae2d5d2f1..8c8a8062eb19 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -479,9 +479,11 @@ static int ioapic_service(struct kvm_ioapic *ioapic, int irq, bool line_status)
 	return ret;
 }
 
-int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int irq_source_id,
-		       int level, bool line_status)
+int kvm_ioapic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
+		       int irq_source_id, int level, bool line_status)
 {
+	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
+	int irq = e->irqchip.pin;
 	int ret, irq_level;
 
 	BUG_ON(irq < 0 || irq >= IOAPIC_NUM_PINS);
diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
index aa8cb4ac0479..a86f59bbea44 100644
--- a/arch/x86/kvm/ioapic.h
+++ b/arch/x86/kvm/ioapic.h
@@ -111,8 +111,9 @@ void kvm_ioapic_update_eoi(struct kvm_vcpu *vcpu, int vector,
 			int trigger_mode);
 int kvm_ioapic_init(struct kvm *kvm);
 void kvm_ioapic_destroy(struct kvm *kvm);
-int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int irq_source_id,
-		       int level, bool line_status);
+int kvm_ioapic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
+		       int irq_source_id, int level, bool line_status);
+
 void kvm_ioapic_clear_all(struct kvm_ioapic *ioapic, int irq_source_id);
 void kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
 void kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index 64f352e7bcb0..8dcb6a555902 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -27,15 +27,6 @@
 #include "x86.h"
 #include "xen.h"
 
-static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
-			      struct kvm *kvm, int irq_source_id, int level,
-			      bool line_status)
-{
-	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
-	return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, irq_source_id, level,
-				line_status);
-}
-
 int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
 		struct kvm_lapic_irq *irq, struct dest_map *dest_map)
 {
@@ -293,7 +284,7 @@ int kvm_set_routing_entry(struct kvm *kvm,
 		case KVM_IRQCHIP_IOAPIC:
 			if (ue->u.irqchip.pin >= KVM_IOAPIC_NUM_PINS)
 				return -EINVAL;
-			e->set = kvm_set_ioapic_irq;
+			e->set = kvm_ioapic_set_irq;
 			break;
 		default:
 			return -EINVAL;
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 04/18] KVM: x86: Drop superfluous kvm_hv_set_sint() => kvm_hv_synic_set_irq() wrapper

[Sean Christopherson]

Drop the superfluous kvm_hv_set_sint() and instead wire up ->set() directly
to its final destination, kvm_hv_synic_set_irq().  Keep hv_synic_set_irq()
instead of kvm_hv_set_sint() to provide some amount of consistency in the
->set() helpers, e.g. to match kvm_pic_set_irq() and kvm_ioapic_set_irq().

kvm_set_msi() is arguably the oddball, e.g. kvm_set_msi_irq() should be
something like kvm_msi_to_lapic_irq() so that kvm_set_msi() can instead be
kvm_set_msi_irq(), but that's a future problem to solve.

No functional change intended.

Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/hyperv.c   | 10 +++++++---
 arch/x86/kvm/hyperv.h   |  3 ++-
 arch/x86/kvm/irq_comm.c | 18 +++---------------
 3 files changed, 12 insertions(+), 19 deletions(-)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 24f0318c50d7..f316e11383aa 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -497,15 +497,19 @@ static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
 	return ret;
 }
 
-int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
+int kvm_hv_synic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
+			 int irq_source_id, int level, bool line_status)
 {
 	struct kvm_vcpu_hv_synic *synic;
 
-	synic = synic_get(kvm, vpidx);
+	if (!level)
+		return -1;
+
+	synic = synic_get(kvm, e->hv_sint.vcpu);
 	if (!synic)
 		return -EINVAL;
 
-	return synic_set_irq(synic, sint);
+	return synic_set_irq(synic, e->hv_sint.sint);
 }
 
 void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index 913bfc96959c..6ce160ffa678 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -103,7 +103,8 @@ static inline bool kvm_hv_hypercall_enabled(struct kvm_vcpu *vcpu)
 int kvm_hv_hypercall(struct kvm_vcpu *vcpu);
 
 void kvm_hv_irq_routing_update(struct kvm *kvm);
-int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vcpu_id, u32 sint);
+int kvm_hv_synic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
+			 int irq_source_id, int level, bool line_status);
 void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector);
 int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages);
 
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index 8dcb6a555902..28a8555ab58b 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -127,18 +127,6 @@ int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
 	return kvm_irq_delivery_to_apic(kvm, NULL, &irq, NULL);
 }
 
-#ifdef CONFIG_KVM_HYPERV
-static int kvm_hv_set_sint(struct kvm_kernel_irq_routing_entry *e,
-		    struct kvm *kvm, int irq_source_id, int level,
-		    bool line_status)
-{
-	if (!level)
-		return -1;
-
-	return kvm_hv_synic_set_irq(kvm, e->hv_sint.vcpu, e->hv_sint.sint);
-}
-#endif
-
 int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
 			      struct kvm *kvm, int irq_source_id, int level,
 			      bool line_status)
@@ -149,8 +137,8 @@ int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
 	switch (e->type) {
 #ifdef CONFIG_KVM_HYPERV
 	case KVM_IRQ_ROUTING_HV_SINT:
-		return kvm_hv_set_sint(e, kvm, irq_source_id, level,
-				       line_status);
+		return kvm_hv_synic_set_irq(e, kvm, irq_source_id, level,
+					    line_status);
 #endif
 
 	case KVM_IRQ_ROUTING_MSI:
@@ -302,7 +290,7 @@ int kvm_set_routing_entry(struct kvm *kvm,
 		break;
 #ifdef CONFIG_KVM_HYPERV
 	case KVM_IRQ_ROUTING_HV_SINT:
-		e->set = kvm_hv_set_sint;
+		e->set = kvm_hv_synic_set_irq;
 		e->hv_sint.vcpu = ue->u.hv_sint.vcpu;
 		e->hv_sint.sint = ue->u.hv_sint.sint;
 		break;
-- 
2.50.0.rc1.591.g9c95f17f64-goog

Re: [PATCH v2 04/18] KVM: x86: Drop superfluous kvm_hv_set_sint() => kvm_hv_synic_set_irq() wrapper

[Huang, Kai]

On Wed, 2025-06-11 at 14:35 -0700, Sean Christopherson wrote:
> Drop the superfluous kvm_hv_set_sint() and instead wire up ->set() directly
> to its final destination, kvm_hv_synic_set_irq().  Keep hv_synic_set_irq()
> instead of kvm_hv_set_sint() to provide some amount of consistency in the
> ->set() helpers, e.g. to match kvm_pic_set_irq() and kvm_ioapic_set_irq().
> 
> kvm_set_msi() is arguably the oddball, e.g. kvm_set_msi_irq() should be
> something like kvm_msi_to_lapic_irq() so that kvm_set_msi() can instead be
> kvm_set_msi_irq(), but that's a future problem to solve.

Agreed on kvm_msi_to_lapic_irq(), but isn't kvm_msi_set_irq() a matter match
to kvm_{pic/ioapic/hv_synic}_set_irq()?  :-)

> 
> No functional change intended.
> 
> Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
> Cc: Kai Huang <kai.huang@intel.com>
> Signed-off-by: Sean Christopherson <seanjc@google.com>

Acked-by: Kai Huang <kai.huang@intel.com>

Re: [PATCH v2 04/18] KVM: x86: Drop superfluous kvm_hv_set_sint() => kvm_hv_synic_set_irq() wrapper

[Sean Christopherson]

On Thu, Jun 12, 2025, Kai Huang wrote:
> On Wed, 2025-06-11 at 14:35 -0700, Sean Christopherson wrote:
> > Drop the superfluous kvm_hv_set_sint() and instead wire up ->set() directly
> > to its final destination, kvm_hv_synic_set_irq().  Keep hv_synic_set_irq()
> > instead of kvm_hv_set_sint() to provide some amount of consistency in the
> > ->set() helpers, e.g. to match kvm_pic_set_irq() and kvm_ioapic_set_irq().
> > 
> > kvm_set_msi() is arguably the oddball, e.g. kvm_set_msi_irq() should be
> > something like kvm_msi_to_lapic_irq() so that kvm_set_msi() can instead be
> > kvm_set_msi_irq(), but that's a future problem to solve.
> 
> Agreed on kvm_msi_to_lapic_irq(), but isn't kvm_msi_set_irq() a matter match
> to kvm_{pic/ioapic/hv_synic}_set_irq()?  :-)

Yes, the problem is that kvm_set_msi() is used by common code, i.e. could actually
be kvm_arch_set_msi_irq().  I'm not entirely sure churning _that_ much code is
worth the marginal improvement in readability.

$ git grep -w kvm_set_msi
arch/arm64/kvm/vgic/vgic-irqfd.c:               e->set = kvm_set_msi;
arch/arm64/kvm/vgic/vgic-irqfd.c: * kvm_set_msi: inject the MSI corresponding to the
arch/arm64/kvm/vgic/vgic-irqfd.c:int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
arch/loongarch/kvm/irqfd.c: * kvm_set_msi: inject the MSI corresponding to the
arch/loongarch/kvm/irqfd.c:int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
arch/loongarch/kvm/irqfd.c:             e->set = kvm_set_msi;
arch/powerpc/kvm/mpic.c:int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
arch/powerpc/kvm/mpic.c:                e->set = kvm_set_msi;
arch/riscv/kvm/vm.c:int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
arch/riscv/kvm/vm.c:            e->set = kvm_set_msi;
arch/riscv/kvm/vm.c:            return kvm_set_msi(e, kvm, irq_source_id, level, line_status);
arch/s390/kvm/interrupt.c:int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
arch/x86/kvm/irq_comm.c:int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
arch/x86/kvm/irq_comm.c:                e->set = kvm_set_msi;
include/linux/kvm_host.h:int kvm_set_msi(struct kvm_kernel_irq_routing_entry *irq_entry, struct kvm *kvm,
virt/kvm/irqchip.c:     return kvm_set_msi(&route, kvm, KVM_USERSPACE_IRQ_SOURCE_ID, 1, false);

Re: [PATCH v2 04/18] KVM: x86: Drop superfluous kvm_hv_set_sint() => kvm_hv_synic_set_irq() wrapper

[Huang, Kai]

On Thu, 2025-06-12 at 17:48 -0700, Sean Christopherson wrote:
> On Thu, Jun 12, 2025, Kai Huang wrote:
> > On Wed, 2025-06-11 at 14:35 -0700, Sean Christopherson wrote:
> > > Drop the superfluous kvm_hv_set_sint() and instead wire up ->set() directly
> > > to its final destination, kvm_hv_synic_set_irq().  Keep hv_synic_set_irq()
> > > instead of kvm_hv_set_sint() to provide some amount of consistency in the
> > > ->set() helpers, e.g. to match kvm_pic_set_irq() and kvm_ioapic_set_irq().
> > > 
> > > kvm_set_msi() is arguably the oddball, e.g. kvm_set_msi_irq() should be
> > > something like kvm_msi_to_lapic_irq() so that kvm_set_msi() can instead be
> > > kvm_set_msi_irq(), but that's a future problem to solve.
> > 
> > Agreed on kvm_msi_to_lapic_irq(), but isn't kvm_msi_set_irq() a matter match
> > to kvm_{pic/ioapic/hv_synic}_set_irq()?  :-)
> 
> Yes, the problem is that kvm_set_msi() is used by common code, i.e. could actually
> be kvm_arch_set_msi_irq().  I'm not entirely sure churning _that_ much code is
> worth the marginal improvement in readability.

Ah didn't know that, then don't bother I guess :-)

Re: [PATCH v2 04/18] KVM: x86: Drop superfluous kvm_hv_set_sint() => kvm_hv_synic_set_irq() wrapper

[Sean Christopherson]

On Fri, Jun 13, 2025, Kai Huang wrote:
> On Thu, 2025-06-12 at 17:48 -0700, Sean Christopherson wrote:
> > On Thu, Jun 12, 2025, Kai Huang wrote:
> > > On Wed, 2025-06-11 at 14:35 -0700, Sean Christopherson wrote:
> > > > Drop the superfluous kvm_hv_set_sint() and instead wire up ->set() directly
> > > > to its final destination, kvm_hv_synic_set_irq().  Keep hv_synic_set_irq()
> > > > instead of kvm_hv_set_sint() to provide some amount of consistency in the
> > > > ->set() helpers, e.g. to match kvm_pic_set_irq() and kvm_ioapic_set_irq().
> > > > 
> > > > kvm_set_msi() is arguably the oddball, e.g. kvm_set_msi_irq() should be
> > > > something like kvm_msi_to_lapic_irq() so that kvm_set_msi() can instead be
> > > > kvm_set_msi_irq(), but that's a future problem to solve.
> > > 
> > > Agreed on kvm_msi_to_lapic_irq(), but isn't kvm_msi_set_irq() a matter match
> > > to kvm_{pic/ioapic/hv_synic}_set_irq()?  :-)
> > 
> > Yes, the problem is that kvm_set_msi() is used by common code, i.e. could actually
> > be kvm_arch_set_msi_irq().  I'm not entirely sure churning _that_ much code is
> > worth the marginal improvement in readability.
> 
> Ah didn't know that

Heh, I didn't know either, until I went to rename the darn thing :-)

Re: [PATCH v2 04/18] KVM: x86: Drop superfluous kvm_hv_set_sint() => kvm_hv_synic_set_irq() wrapper

[Vitaly Kuznetsov]

Sean Christopherson <seanjc@google.com> writes:

> Drop the superfluous kvm_hv_set_sint() and instead wire up ->set() directly
> to its final destination, kvm_hv_synic_set_irq().  Keep hv_synic_set_irq()
> instead of kvm_hv_set_sint() to provide some amount of consistency in the
> ->set() helpers, e.g. to match kvm_pic_set_irq() and kvm_ioapic_set_irq().
>
> kvm_set_msi() is arguably the oddball, e.g. kvm_set_msi_irq() should be
> something like kvm_msi_to_lapic_irq() so that kvm_set_msi() can instead be
> kvm_set_msi_irq(), but that's a future problem to solve.
>
> No functional change intended.
>
> Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
> Cc: Kai Huang <kai.huang@intel.com>
> Signed-off-by: Sean Christopherson <seanjc@google.com>

Sorry for the delay,

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>

> ---
>  arch/x86/kvm/hyperv.c   | 10 +++++++---
>  arch/x86/kvm/hyperv.h   |  3 ++-
>  arch/x86/kvm/irq_comm.c | 18 +++---------------
>  3 files changed, 12 insertions(+), 19 deletions(-)
>
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index 24f0318c50d7..f316e11383aa 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -497,15 +497,19 @@ static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
>  	return ret;
>  }
>  
> -int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
> +int kvm_hv_synic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
> +			 int irq_source_id, int level, bool line_status)
>  {
>  	struct kvm_vcpu_hv_synic *synic;
>  
> -	synic = synic_get(kvm, vpidx);
> +	if (!level)
> +		return -1;
> +
> +	synic = synic_get(kvm, e->hv_sint.vcpu);
>  	if (!synic)
>  		return -EINVAL;
>  
> -	return synic_set_irq(synic, sint);
> +	return synic_set_irq(synic, e->hv_sint.sint);
>  }
>  
>  void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
> diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
> index 913bfc96959c..6ce160ffa678 100644
> --- a/arch/x86/kvm/hyperv.h
> +++ b/arch/x86/kvm/hyperv.h
> @@ -103,7 +103,8 @@ static inline bool kvm_hv_hypercall_enabled(struct kvm_vcpu *vcpu)
>  int kvm_hv_hypercall(struct kvm_vcpu *vcpu);
>  
>  void kvm_hv_irq_routing_update(struct kvm *kvm);
> -int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vcpu_id, u32 sint);
> +int kvm_hv_synic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
> +			 int irq_source_id, int level, bool line_status);
>  void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector);
>  int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages);
>  
> diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
> index 8dcb6a555902..28a8555ab58b 100644
> --- a/arch/x86/kvm/irq_comm.c
> +++ b/arch/x86/kvm/irq_comm.c
> @@ -127,18 +127,6 @@ int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
>  	return kvm_irq_delivery_to_apic(kvm, NULL, &irq, NULL);
>  }
>  
> -#ifdef CONFIG_KVM_HYPERV
> -static int kvm_hv_set_sint(struct kvm_kernel_irq_routing_entry *e,
> -		    struct kvm *kvm, int irq_source_id, int level,
> -		    bool line_status)
> -{
> -	if (!level)
> -		return -1;
> -
> -	return kvm_hv_synic_set_irq(kvm, e->hv_sint.vcpu, e->hv_sint.sint);
> -}
> -#endif
> -
>  int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
>  			      struct kvm *kvm, int irq_source_id, int level,
>  			      bool line_status)
> @@ -149,8 +137,8 @@ int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
>  	switch (e->type) {
>  #ifdef CONFIG_KVM_HYPERV
>  	case KVM_IRQ_ROUTING_HV_SINT:
> -		return kvm_hv_set_sint(e, kvm, irq_source_id, level,
> -				       line_status);
> +		return kvm_hv_synic_set_irq(e, kvm, irq_source_id, level,
> +					    line_status);
>  #endif
>  
>  	case KVM_IRQ_ROUTING_MSI:
> @@ -302,7 +290,7 @@ int kvm_set_routing_entry(struct kvm *kvm,
>  		break;
>  #ifdef CONFIG_KVM_HYPERV
>  	case KVM_IRQ_ROUTING_HV_SINT:
> -		e->set = kvm_hv_set_sint;
> +		e->set = kvm_hv_synic_set_irq;
>  		e->hv_sint.vcpu = ue->u.hv_sint.vcpu;
>  		e->hv_sint.sint = ue->u.hv_sint.sint;
>  		break;

-- 
Vitaly

[PATCH v2 05/18] KVM: x86: Move PIT ioctl helpers to i8254.c

[Sean Christopherson]

Move the PIT ioctl helpers to i8254.c, i.e. to the file that implements
PIT emulation.  Eliminating PIT code in x86.c will allow adding a Kconfig
to control support for in-kernel I/O APIC, PIC, and PIT emulation with
minimal #ifdefs.

Opportunistically make kvm_pit_set_reinject() and kvm_pit_load_count()
local to i8254.c as they were only publicly visible to make them available
to the ioctl helpers.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/i8254.c | 79 ++++++++++++++++++++++++++++++++++++++++++--
 arch/x86/kvm/i8254.h | 12 ++++---
 arch/x86/kvm/x86.c   | 74 -----------------------------------------
 3 files changed, 84 insertions(+), 81 deletions(-)

diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 739aa6c0d0c3..59f956f35f4c 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -288,7 +288,7 @@ static inline void kvm_pit_reset_reinject(struct kvm_pit *pit)
 	atomic_set(&pit->pit_state.irq_ack, 1);
 }
 
-void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject)
+static void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject)
 {
 	struct kvm_kpit_state *ps = &pit->pit_state;
 	struct kvm *kvm = pit->kvm;
@@ -400,8 +400,8 @@ static void pit_load_count(struct kvm_pit *pit, int channel, u32 val)
 	}
 }
 
-void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
-		int hpet_legacy_start)
+static void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
+			       int hpet_legacy_start)
 {
 	u8 saved_mode;
 
@@ -649,6 +649,79 @@ static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask)
 		kvm_pit_reset_reinject(pit);
 }
 
+int kvm_vm_ioctl_get_pit(struct kvm *kvm, struct kvm_pit_state *ps)
+{
+	struct kvm_kpit_state *kps = &kvm->arch.vpit->pit_state;
+
+	BUILD_BUG_ON(sizeof(*ps) != sizeof(kps->channels));
+
+	mutex_lock(&kps->lock);
+	memcpy(ps, &kps->channels, sizeof(*ps));
+	mutex_unlock(&kps->lock);
+	return 0;
+}
+
+int kvm_vm_ioctl_set_pit(struct kvm *kvm, struct kvm_pit_state *ps)
+{
+	int i;
+	struct kvm_pit *pit = kvm->arch.vpit;
+
+	mutex_lock(&pit->pit_state.lock);
+	memcpy(&pit->pit_state.channels, ps, sizeof(*ps));
+	for (i = 0; i < 3; i++)
+		kvm_pit_load_count(pit, i, ps->channels[i].count, 0);
+	mutex_unlock(&pit->pit_state.lock);
+	return 0;
+}
+
+int kvm_vm_ioctl_get_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps)
+{
+	mutex_lock(&kvm->arch.vpit->pit_state.lock);
+	memcpy(ps->channels, &kvm->arch.vpit->pit_state.channels,
+		sizeof(ps->channels));
+	ps->flags = kvm->arch.vpit->pit_state.flags;
+	mutex_unlock(&kvm->arch.vpit->pit_state.lock);
+	memset(&ps->reserved, 0, sizeof(ps->reserved));
+	return 0;
+}
+
+int kvm_vm_ioctl_set_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps)
+{
+	int start = 0;
+	int i;
+	u32 prev_legacy, cur_legacy;
+	struct kvm_pit *pit = kvm->arch.vpit;
+
+	mutex_lock(&pit->pit_state.lock);
+	prev_legacy = pit->pit_state.flags & KVM_PIT_FLAGS_HPET_LEGACY;
+	cur_legacy = ps->flags & KVM_PIT_FLAGS_HPET_LEGACY;
+	if (!prev_legacy && cur_legacy)
+		start = 1;
+	memcpy(&pit->pit_state.channels, &ps->channels,
+	       sizeof(pit->pit_state.channels));
+	pit->pit_state.flags = ps->flags;
+	for (i = 0; i < 3; i++)
+		kvm_pit_load_count(pit, i, pit->pit_state.channels[i].count,
+				   start && i == 0);
+	mutex_unlock(&pit->pit_state.lock);
+	return 0;
+}
+
+int kvm_vm_ioctl_reinject(struct kvm *kvm, struct kvm_reinject_control *control)
+{
+	struct kvm_pit *pit = kvm->arch.vpit;
+
+	/* pit->pit_state.lock was overloaded to prevent userspace from getting
+	 * an inconsistent state after running multiple KVM_REINJECT_CONTROL
+	 * ioctls in parallel.  Use a separate lock if that ioctl isn't rare.
+	 */
+	mutex_lock(&pit->pit_state.lock);
+	kvm_pit_set_reinject(pit, control->pit_reinject);
+	mutex_unlock(&pit->pit_state.lock);
+
+	return 0;
+}
+
 static const struct kvm_io_device_ops pit_dev_ops = {
 	.read     = pit_ioport_read,
 	.write    = pit_ioport_write,
diff --git a/arch/x86/kvm/i8254.h b/arch/x86/kvm/i8254.h
index a768212ba821..338095829ec8 100644
--- a/arch/x86/kvm/i8254.h
+++ b/arch/x86/kvm/i8254.h
@@ -6,6 +6,8 @@
 
 #include <kvm/iodev.h>
 
+#include <uapi/asm/kvm.h>
+
 struct kvm_kpit_channel_state {
 	u32 count; /* can be 65536 */
 	u16 latched_count;
@@ -55,11 +57,13 @@ struct kvm_pit {
 #define KVM_MAX_PIT_INTR_INTERVAL   HZ / 100
 #define KVM_PIT_CHANNEL_MASK	    0x3
 
+int kvm_vm_ioctl_get_pit(struct kvm *kvm, struct kvm_pit_state *ps);
+int kvm_vm_ioctl_set_pit(struct kvm *kvm, struct kvm_pit_state *ps);
+int kvm_vm_ioctl_get_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps);
+int kvm_vm_ioctl_set_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps);
+int kvm_vm_ioctl_reinject(struct kvm *kvm, struct kvm_reinject_control *control);
+
 struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags);
 void kvm_free_pit(struct kvm *kvm);
 
-void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
-		int hpet_legacy_start);
-void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject);
-
 #endif
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index dd34a2ec854c..50e9fa57b859 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6450,80 +6450,6 @@ static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
 	return r;
 }
 
-static int kvm_vm_ioctl_get_pit(struct kvm *kvm, struct kvm_pit_state *ps)
-{
-	struct kvm_kpit_state *kps = &kvm->arch.vpit->pit_state;
-
-	BUILD_BUG_ON(sizeof(*ps) != sizeof(kps->channels));
-
-	mutex_lock(&kps->lock);
-	memcpy(ps, &kps->channels, sizeof(*ps));
-	mutex_unlock(&kps->lock);
-	return 0;
-}
-
-static int kvm_vm_ioctl_set_pit(struct kvm *kvm, struct kvm_pit_state *ps)
-{
-	int i;
-	struct kvm_pit *pit = kvm->arch.vpit;
-
-	mutex_lock(&pit->pit_state.lock);
-	memcpy(&pit->pit_state.channels, ps, sizeof(*ps));
-	for (i = 0; i < 3; i++)
-		kvm_pit_load_count(pit, i, ps->channels[i].count, 0);
-	mutex_unlock(&pit->pit_state.lock);
-	return 0;
-}
-
-static int kvm_vm_ioctl_get_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps)
-{
-	mutex_lock(&kvm->arch.vpit->pit_state.lock);
-	memcpy(ps->channels, &kvm->arch.vpit->pit_state.channels,
-		sizeof(ps->channels));
-	ps->flags = kvm->arch.vpit->pit_state.flags;
-	mutex_unlock(&kvm->arch.vpit->pit_state.lock);
-	memset(&ps->reserved, 0, sizeof(ps->reserved));
-	return 0;
-}
-
-static int kvm_vm_ioctl_set_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps)
-{
-	int start = 0;
-	int i;
-	u32 prev_legacy, cur_legacy;
-	struct kvm_pit *pit = kvm->arch.vpit;
-
-	mutex_lock(&pit->pit_state.lock);
-	prev_legacy = pit->pit_state.flags & KVM_PIT_FLAGS_HPET_LEGACY;
-	cur_legacy = ps->flags & KVM_PIT_FLAGS_HPET_LEGACY;
-	if (!prev_legacy && cur_legacy)
-		start = 1;
-	memcpy(&pit->pit_state.channels, &ps->channels,
-	       sizeof(pit->pit_state.channels));
-	pit->pit_state.flags = ps->flags;
-	for (i = 0; i < 3; i++)
-		kvm_pit_load_count(pit, i, pit->pit_state.channels[i].count,
-				   start && i == 0);
-	mutex_unlock(&pit->pit_state.lock);
-	return 0;
-}
-
-static int kvm_vm_ioctl_reinject(struct kvm *kvm,
-				 struct kvm_reinject_control *control)
-{
-	struct kvm_pit *pit = kvm->arch.vpit;
-
-	/* pit->pit_state.lock was overloaded to prevent userspace from getting
-	 * an inconsistent state after running multiple KVM_REINJECT_CONTROL
-	 * ioctls in parallel.  Use a separate lock if that ioctl isn't rare.
-	 */
-	mutex_lock(&pit->pit_state.lock);
-	kvm_pit_set_reinject(pit, control->pit_reinject);
-	mutex_unlock(&pit->pit_state.lock);
-
-	return 0;
-}
-
 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
 {
 
-- 
2.50.0.rc1.591.g9c95f17f64-goog

Re: [PATCH v2 05/18] KVM: x86: Move PIT ioctl helpers to i8254.c

[Huang, Kai]

On Wed, 2025-06-11 at 14:35 -0700, Sean Christopherson wrote:
> Move the PIT ioctl helpers to i8254.c, i.e. to the file that implements
> PIT emulation.  Eliminating PIT code in x86.c will allow adding a Kconfig
> to control support for in-kernel I/O APIC, PIC, and PIT emulation with
> minimal #ifdefs.

And it matches the other (existing) ioctl helpers which are under
CONFIG_KVM_HYPERV [*] and CONFIG_KVM_XEN too.

[*]:  The kvm_ioctl_get_supported_hv_cpuid() seems to be the only one that
still remains in kvm/x86.c but not in kvm/hyperv.c.

> 
> Opportunistically make kvm_pit_set_reinject() and kvm_pit_load_count()
> local to i8254.c as they were only publicly visible to make them available
> to the ioctl helpers.
> 
> No functional change intended.
> 
> Signed-off-by: Sean Christopherson <seanjc@google.com>
> ---

Acked-by: Kai Huang <kai.huang@intel.com>

Re: [PATCH v2 05/18] KVM: x86: Move PIT ioctl helpers to i8254.c

[Sean Christopherson]

On Thu, Jun 12, 2025, Kai Huang wrote:
> On Wed, 2025-06-11 at 14:35 -0700, Sean Christopherson wrote:
> > Move the PIT ioctl helpers to i8254.c, i.e. to the file that implements
> > PIT emulation.  Eliminating PIT code in x86.c will allow adding a Kconfig
> > to control support for in-kernel I/O APIC, PIC, and PIT emulation with
> > minimal #ifdefs.
> 
> And it matches the other (existing) ioctl helpers which are under
> CONFIG_KVM_HYPERV [*] and CONFIG_KVM_XEN too.
> 
> [*]:  The kvm_ioctl_get_supported_hv_cpuid() seems to be the only one that
> still remains in kvm/x86.c but not in kvm/hyperv.c.

Ooh, yeah, that'd be a good one to move out of x86.c.

[PATCH v2 06/18] KVM: x86: Move KVM_{GET,SET}_IRQCHIP ioctl helpers to irq.c

[Sean Christopherson]

Move the ioctl helpers for getting/setting fully in-kernel IRQ chip state
to irq.c, partly to trim down x86.c, but mostly in preparation for adding
a Kconfig to control support for in-kernel I/O APIC, PIC, and PIT
emulation.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/irq.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++
 arch/x86/kvm/irq.h |  3 +++
 arch/x86/kvm/x86.c | 55 ---------------------------------------------
 3 files changed, 59 insertions(+), 55 deletions(-)

diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index 97d68d837929..da47e2165389 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -12,6 +12,7 @@
 #include <linux/export.h>
 #include <linux/kvm_host.h>
 
+#include "ioapic.h"
 #include "irq.h"
 #include "i8254.h"
 #include "x86.h"
@@ -178,3 +179,58 @@ bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
 {
 	return irqchip_in_kernel(kvm);
 }
+
+int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
+{
+	struct kvm_pic *pic = kvm->arch.vpic;
+	int r;
+
+	r = 0;
+	switch (chip->chip_id) {
+	case KVM_IRQCHIP_PIC_MASTER:
+		memcpy(&chip->chip.pic, &pic->pics[0],
+			sizeof(struct kvm_pic_state));
+		break;
+	case KVM_IRQCHIP_PIC_SLAVE:
+		memcpy(&chip->chip.pic, &pic->pics[1],
+			sizeof(struct kvm_pic_state));
+		break;
+	case KVM_IRQCHIP_IOAPIC:
+		kvm_get_ioapic(kvm, &chip->chip.ioapic);
+		break;
+	default:
+		r = -EINVAL;
+		break;
+	}
+	return r;
+}
+
+int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
+{
+	struct kvm_pic *pic = kvm->arch.vpic;
+	int r;
+
+	r = 0;
+	switch (chip->chip_id) {
+	case KVM_IRQCHIP_PIC_MASTER:
+		spin_lock(&pic->lock);
+		memcpy(&pic->pics[0], &chip->chip.pic,
+			sizeof(struct kvm_pic_state));
+		spin_unlock(&pic->lock);
+		break;
+	case KVM_IRQCHIP_PIC_SLAVE:
+		spin_lock(&pic->lock);
+		memcpy(&pic->pics[1], &chip->chip.pic,
+			sizeof(struct kvm_pic_state));
+		spin_unlock(&pic->lock);
+		break;
+	case KVM_IRQCHIP_IOAPIC:
+		kvm_set_ioapic(kvm, &chip->chip.ioapic);
+		break;
+	default:
+		r = -EINVAL;
+		break;
+	}
+	kvm_pic_update_irq(pic);
+	return r;
+}
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 33dd5666b656..aa77a6b2828c 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -66,6 +66,9 @@ void kvm_pic_update_irq(struct kvm_pic *s);
 int kvm_pic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
 		    int irq_source_id, int level, bool line_status);
 
+int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);
+int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);
+
 static inline int irqchip_split(struct kvm *kvm)
 {
 	int mode = kvm->arch.irqchip_mode;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 50e9fa57b859..311a670b6652 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6395,61 +6395,6 @@ static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm,
 	return 0;
 }
 
-static int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
-{
-	struct kvm_pic *pic = kvm->arch.vpic;
-	int r;
-
-	r = 0;
-	switch (chip->chip_id) {
-	case KVM_IRQCHIP_PIC_MASTER:
-		memcpy(&chip->chip.pic, &pic->pics[0],
-			sizeof(struct kvm_pic_state));
-		break;
-	case KVM_IRQCHIP_PIC_SLAVE:
-		memcpy(&chip->chip.pic, &pic->pics[1],
-			sizeof(struct kvm_pic_state));
-		break;
-	case KVM_IRQCHIP_IOAPIC:
-		kvm_get_ioapic(kvm, &chip->chip.ioapic);
-		break;
-	default:
-		r = -EINVAL;
-		break;
-	}
-	return r;
-}
-
-static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
-{
-	struct kvm_pic *pic = kvm->arch.vpic;
-	int r;
-
-	r = 0;
-	switch (chip->chip_id) {
-	case KVM_IRQCHIP_PIC_MASTER:
-		spin_lock(&pic->lock);
-		memcpy(&pic->pics[0], &chip->chip.pic,
-			sizeof(struct kvm_pic_state));
-		spin_unlock(&pic->lock);
-		break;
-	case KVM_IRQCHIP_PIC_SLAVE:
-		spin_lock(&pic->lock);
-		memcpy(&pic->pics[1], &chip->chip.pic,
-			sizeof(struct kvm_pic_state));
-		spin_unlock(&pic->lock);
-		break;
-	case KVM_IRQCHIP_IOAPIC:
-		kvm_set_ioapic(kvm, &chip->chip.ioapic);
-		break;
-	default:
-		r = -EINVAL;
-		break;
-	}
-	kvm_pic_update_irq(pic);
-	return r;
-}
-
 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
 {
 
-- 
2.50.0.rc1.591.g9c95f17f64-goog

Re: [PATCH v2 06/18] KVM: x86: Move KVM_{GET,SET}_IRQCHIP ioctl helpers to irq.c

[Huang, Kai]

On Wed, 2025-06-11 at 14:35 -0700, Sean Christopherson wrote:
> Move the ioctl helpers for getting/setting fully in-kernel IRQ chip state
> to irq.c, partly to trim down x86.c, but mostly in preparation for adding
> a Kconfig to control support for in-kernel I/O APIC, PIC, and PIT
> emulation.
> 
> No functional change intended.
> 
> Signed-off-by: Sean Christopherson <seanjc@google.com>
> ---

Acked-by: Kai Huang <kai.huang@intel.com>

[...]

> --- a/arch/x86/kvm/irq.h
> +++ b/arch/x86/kvm/irq.h
> @@ -66,6 +66,9 @@ void kvm_pic_update_irq(struct kvm_pic *s);
>  int kvm_pic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
>  		    int irq_source_id, int level, bool line_status);
>  
> +int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);
> +int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);
> +

I think we need to include <uapi/linux/kvm.h> for 'struct kvm_irqchip', just
like you did for "i8254.h" in previous patch?

I checked the "irq.h" and it doesn't seem to be obvious that we don't need
it.

Re: [PATCH v2 06/18] KVM: x86: Move KVM_{GET,SET}_IRQCHIP ioctl helpers to irq.c

[Sean Christopherson]

On Thu, Jun 12, 2025, Kai Huang wrote:
> On Wed, 2025-06-11 at 14:35 -0700, Sean Christopherson wrote:
> > Move the ioctl helpers for getting/setting fully in-kernel IRQ chip state
> > to irq.c, partly to trim down x86.c, but mostly in preparation for adding
> > a Kconfig to control support for in-kernel I/O APIC, PIC, and PIT
> > emulation.
> > 
> > No functional change intended.
> > 
> > Signed-off-by: Sean Christopherson <seanjc@google.com>
> > ---
> 
> Acked-by: Kai Huang <kai.huang@intel.com>
> 
> [...]
> 
> > --- a/arch/x86/kvm/irq.h
> > +++ b/arch/x86/kvm/irq.h
> > @@ -66,6 +66,9 @@ void kvm_pic_update_irq(struct kvm_pic *s);
> >  int kvm_pic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
> >  		    int irq_source_id, int level, bool line_status);
> >  
> > +int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);
> > +int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);
> > +
> 
> I think we need to include <uapi/linux/kvm.h> for 'struct kvm_irqchip', just
> like you did for "i8254.h" in previous patch?

It gets pulled in by linux/kvm_host.h.  i8254.h didn't have that one (though
amusingly, later on it does get kvm_host.h indirectly via ioapic.h).

> I checked the "irq.h" and it doesn't seem to be obvious that we don't need
> it.

[PATCH v2 07/18] KVM: x86: Rename irqchip_kernel() to irqchip_full()

[Sean Christopherson]

Rename irqchip_kernel() to irqchip_full(), as "kernel" is very ambiguous
due to the existence of split IRQ chip support, where only some of the
"irqchip" is in emulated by the kernel/KVM.  E.g. irqchip_kernel() often
gets confused with irqchip_in_kernel().

Opportunistically hoist the definition up in irq.h so that it's
co-located with other "full" irqchip code in anticipation of wrapping it
all with a Kconfig/#ifdef.

No functional change intended.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/ioapic.h   |  2 +-
 arch/x86/kvm/irq.c      |  2 +-
 arch/x86/kvm/irq.h      | 22 +++++++++++-----------
 arch/x86/kvm/irq_comm.c |  2 +-
 arch/x86/kvm/x86.c      |  4 ++--
 5 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
index a86f59bbea44..289cca3aec69 100644
--- a/arch/x86/kvm/ioapic.h
+++ b/arch/x86/kvm/ioapic.h
@@ -103,7 +103,7 @@ do {									\
 
 static inline int ioapic_in_kernel(struct kvm *kvm)
 {
-	return irqchip_kernel(kvm);
+	return irqchip_full(kvm);
 }
 
 void kvm_rtc_eoi_tracking_restore_one(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index da47e2165389..97e1617ce24d 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -172,7 +172,7 @@ bool kvm_arch_irqfd_allowed(struct kvm *kvm, struct kvm_irqfd *args)
 {
 	bool resample = args->flags & KVM_IRQFD_FLAG_RESAMPLE;
 
-	return resample ? irqchip_kernel(kvm) : irqchip_in_kernel(kvm);
+	return resample ? irqchip_full(kvm) : irqchip_in_kernel(kvm);
 }
 
 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index aa77a6b2828c..4ac346102350 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -69,16 +69,7 @@ int kvm_pic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
 int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);
 int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);
 
-static inline int irqchip_split(struct kvm *kvm)
-{
-	int mode = kvm->arch.irqchip_mode;
-
-	/* Matches smp_wmb() when setting irqchip_mode */
-	smp_rmb();
-	return mode == KVM_IRQCHIP_SPLIT;
-}
-
-static inline int irqchip_kernel(struct kvm *kvm)
+static inline int irqchip_full(struct kvm *kvm)
 {
 	int mode = kvm->arch.irqchip_mode;
 
@@ -89,7 +80,16 @@ static inline int irqchip_kernel(struct kvm *kvm)
 
 static inline int pic_in_kernel(struct kvm *kvm)
 {
-	return irqchip_kernel(kvm);
+	return irqchip_full(kvm);
+}
+
+static inline int irqchip_split(struct kvm *kvm)
+{
+	int mode = kvm->arch.irqchip_mode;
+
+	/* Matches smp_wmb() when setting irqchip_mode */
+	smp_rmb();
+	return mode == KVM_IRQCHIP_SPLIT;
 }
 
 static inline int irqchip_in_kernel(struct kvm *kvm)
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index 28a8555ab58b..bcf2f1e4a005 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -200,7 +200,7 @@ void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
 		goto unlock;
 	}
 	clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
-	if (!irqchip_kernel(kvm))
+	if (!irqchip_full(kvm))
 		goto unlock;
 
 	kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 311a670b6652..fb7b0d301c38 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7039,7 +7039,7 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 		}
 
 		r = -ENXIO;
-		if (!irqchip_kernel(kvm))
+		if (!irqchip_full(kvm))
 			goto get_irqchip_out;
 		r = kvm_vm_ioctl_get_irqchip(kvm, chip);
 		if (r)
@@ -7063,7 +7063,7 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 		}
 
 		r = -ENXIO;
-		if (!irqchip_kernel(kvm))
+		if (!irqchip_full(kvm))
 			goto set_irqchip_out;
 		r = kvm_vm_ioctl_set_irqchip(kvm, chip);
 	set_irqchip_out:
-- 
2.50.0.rc1.591.g9c95f17f64-goog

Re: [PATCH v2 07/18] KVM: x86: Rename irqchip_kernel() to irqchip_full()

[Huang, Kai]

On Wed, 2025-06-11 at 14:35 -0700, Sean Christopherson wrote:
> Rename irqchip_kernel() to irqchip_full(), as "kernel" is very ambiguous
> due to the existence of split IRQ chip support, where only some of the
> "irqchip" is in emulated by the kernel/KVM.  E.g. irqchip_kernel() often

"is in emulated" -> "is emulated".

Or did you mean:

"is emulated in the kernel/KVM"?

> gets confused with irqchip_in_kernel().
> 
> Opportunistically hoist the definition up in irq.h so that it's
> co-located with other "full" irqchip code in anticipation of wrapping it
> all with a Kconfig/#ifdef.
> 
> No functional change intended.
> 
> Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Sean Christopherson <seanjc@google.com>

Acked-by: Kai Huang <kai.huang@intel.com>

Re: [PATCH v2 07/18] KVM: x86: Rename irqchip_kernel() to irqchip_full()

[Sean Christopherson]

On Thu, Jun 12, 2025, Kai Huang wrote:
> On Wed, 2025-06-11 at 14:35 -0700, Sean Christopherson wrote:
> > Rename irqchip_kernel() to irqchip_full(), as "kernel" is very ambiguous
> > due to the existence of split IRQ chip support, where only some of the
> > "irqchip" is in emulated by the kernel/KVM.  E.g. irqchip_kernel() often
> 
> "is in emulated" -> "is emulated".
> 
> Or did you mean:
> 
> "is emulated in the kernel/KVM"?

Heh, both?  I'll go with "is emulated".  IIRC, I was trying to choose between
the two options you listed, and didn't quite get the cleanup right.

[PATCH v2 08/18] KVM: x86: Move kvm_setup_default_irq_routing() into irq.c

[Sean Christopherson]

Move the default IRQ routing table used for in-kernel I/O APIC and PIC
routing to irq.c, and tweak the name to make it explicitly clear what
routing is being initialized.

In addition to making it more obvious that the so called "default" routing
only applies to an in-kernel I/O APIC, getting it out of irq_comm.c will
allow removing irq_comm.c entirely.  And placing the function alongside
other I/O APIC and PIC code will allow for guarding KVM's in-kernel I/O
APIC and PIC emulation with a Kconfig with minimal #ifdefs.

No functional change intended.

Cc: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/irq.c      | 32 ++++++++++++++++++++++++++++++++
 arch/x86/kvm/irq.h      |  3 ++-
 arch/x86/kvm/irq_comm.c | 32 --------------------------------
 arch/x86/kvm/x86.c      |  2 +-
 4 files changed, 35 insertions(+), 34 deletions(-)

diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index 97e1617ce24d..b696161ec078 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -180,6 +180,38 @@ bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
 	return irqchip_in_kernel(kvm);
 }
 
+#define IOAPIC_ROUTING_ENTRY(irq) \
+	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
+	  .u.irqchip = { .irqchip = KVM_IRQCHIP_IOAPIC, .pin = (irq) } }
+#define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
+
+#define PIC_ROUTING_ENTRY(irq) \
+	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
+	  .u.irqchip = { .irqchip = SELECT_PIC(irq), .pin = (irq) % 8 } }
+#define ROUTING_ENTRY2(irq) \
+	IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
+
+static const struct kvm_irq_routing_entry default_routing[] = {
+	ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
+	ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
+	ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
+	ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
+	ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
+	ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
+	ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
+	ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
+	ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
+	ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
+	ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
+	ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
+};
+
+int kvm_setup_default_ioapic_and_pic_routing(struct kvm *kvm)
+{
+	return kvm_set_irq_routing(kvm, default_routing,
+				   ARRAY_SIZE(default_routing), 0);
+}
+
 int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
 {
 	struct kvm_pic *pic = kvm->arch.vpic;
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 4ac346102350..7b8b54462f95 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -66,6 +66,8 @@ void kvm_pic_update_irq(struct kvm_pic *s);
 int kvm_pic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
 		    int irq_source_id, int level, bool line_status);
 
+int kvm_setup_default_ioapic_and_pic_routing(struct kvm *kvm);
+
 int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);
 int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);
 
@@ -110,7 +112,6 @@ void __kvm_migrate_timers(struct kvm_vcpu *vcpu);
 
 int apic_has_pending_timer(struct kvm_vcpu *vcpu);
 
-int kvm_setup_default_irq_routing(struct kvm *kvm);
 int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
 			     struct kvm_lapic_irq *irq,
 			     struct dest_map *dest_map);
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index bcf2f1e4a005..99c521bd9db5 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -334,38 +334,6 @@ bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq,
 }
 EXPORT_SYMBOL_GPL(kvm_intr_is_single_vcpu);
 
-#define IOAPIC_ROUTING_ENTRY(irq) \
-	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
-	  .u.irqchip = { .irqchip = KVM_IRQCHIP_IOAPIC, .pin = (irq) } }
-#define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
-
-#define PIC_ROUTING_ENTRY(irq) \
-	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
-	  .u.irqchip = { .irqchip = SELECT_PIC(irq), .pin = (irq) % 8 } }
-#define ROUTING_ENTRY2(irq) \
-	IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
-
-static const struct kvm_irq_routing_entry default_routing[] = {
-	ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
-	ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
-	ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
-	ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
-	ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
-	ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
-	ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
-	ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
-	ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
-	ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
-	ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
-	ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
-};
-
-int kvm_setup_default_irq_routing(struct kvm *kvm)
-{
-	return kvm_set_irq_routing(kvm, default_routing,
-				   ARRAY_SIZE(default_routing), 0);
-}
-
 void kvm_scan_ioapic_irq(struct kvm_vcpu *vcpu, u32 dest_id, u16 dest_mode,
 			 u8 vector, unsigned long *ioapic_handled_vectors)
 {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fb7b0d301c38..f02a9a332f69 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6991,7 +6991,7 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 			goto create_irqchip_unlock;
 		}
 
-		r = kvm_setup_default_irq_routing(kvm);
+		r = kvm_setup_default_ioapic_and_pic_routing(kvm);
 		if (r) {
 			kvm_ioapic_destroy(kvm);
 			kvm_pic_destroy(kvm);
-- 
2.50.0.rc1.591.g9c95f17f64-goog

Re: [PATCH v2 08/18] KVM: x86: Move kvm_setup_default_irq_routing() into irq.c

[Huang, Kai]

On Wed, 2025-06-11 at 14:35 -0700, Sean Christopherson wrote:
> Move the default IRQ routing table used for in-kernel I/O APIC and PIC
> routing to irq.c, and tweak the name to make it explicitly clear what
> routing is being initialized.
> 
> In addition to making it more obvious that the so called "default" routing
> only applies to an in-kernel I/O APIC, getting it out of irq_comm.c will
> allow removing irq_comm.c entirely.  And placing the function alongside
> other I/O APIC and PIC code will allow for guarding KVM's in-kernel I/O
> APIC and PIC emulation with a Kconfig with minimal #ifdefs.
> 
> No functional change intended.
> 
> Cc: Kai Huang <kai.huang@intel.com>
> Signed-off-by: Sean Christopherson <seanjc@google.com>
> 

Acked-by: Kai Huang <kai.huang@intel.com>

[PATCH v2 09/18] KVM: x86: Move kvm_{request,free}_irq_source_id() to i8254.c (PIT)

[Sean Christopherson]

Move kvm_{request,free}_irq_source_id() to i8254.c, i.e. the dedicated PIT
emulation file, in anticipation of removing them entirely in favor of
hardcoding the PIT's "requested" source ID (the source ID can only ever be
'2', and the request can never fail).

No functional change intended.

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/i8254.c     | 44 ++++++++++++++++++++++++++++++++++++++++
 arch/x86/kvm/irq_comm.c  | 44 ----------------------------------------
 include/linux/kvm_host.h |  2 --
 3 files changed, 44 insertions(+), 46 deletions(-)

diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 59f956f35f4c..2bb223bf0dac 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -641,6 +641,50 @@ static void kvm_pit_reset(struct kvm_pit *pit)
 	kvm_pit_reset_reinject(pit);
 }
 
+static int kvm_request_irq_source_id(struct kvm *kvm)
+{
+	unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
+	int irq_source_id;
+
+	mutex_lock(&kvm->irq_lock);
+	irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
+
+	if (irq_source_id >= BITS_PER_LONG) {
+		pr_warn("exhausted allocatable IRQ sources!\n");
+		irq_source_id = -EFAULT;
+		goto unlock;
+	}
+
+	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
+	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
+	set_bit(irq_source_id, bitmap);
+unlock:
+	mutex_unlock(&kvm->irq_lock);
+
+	return irq_source_id;
+}
+
+static void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
+{
+	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
+	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
+
+	mutex_lock(&kvm->irq_lock);
+	if (irq_source_id < 0 ||
+	    irq_source_id >= BITS_PER_LONG) {
+		pr_err("IRQ source ID out of range!\n");
+		goto unlock;
+	}
+	clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
+	if (!irqchip_full(kvm))
+		goto unlock;
+
+	kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
+	kvm_pic_clear_all(kvm->arch.vpic, irq_source_id);
+unlock:
+	mutex_unlock(&kvm->irq_lock);
+}
+
 static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask)
 {
 	struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier);
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index 99c521bd9db5..138c675dc24b 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -165,50 +165,6 @@ int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
 	return -EWOULDBLOCK;
 }
 
-int kvm_request_irq_source_id(struct kvm *kvm)
-{
-	unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
-	int irq_source_id;
-
-	mutex_lock(&kvm->irq_lock);
-	irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
-
-	if (irq_source_id >= BITS_PER_LONG) {
-		pr_warn("exhausted allocatable IRQ sources!\n");
-		irq_source_id = -EFAULT;
-		goto unlock;
-	}
-
-	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
-	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
-	set_bit(irq_source_id, bitmap);
-unlock:
-	mutex_unlock(&kvm->irq_lock);
-
-	return irq_source_id;
-}
-
-void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
-{
-	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
-	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
-
-	mutex_lock(&kvm->irq_lock);
-	if (irq_source_id < 0 ||
-	    irq_source_id >= BITS_PER_LONG) {
-		pr_err("IRQ source ID out of range!\n");
-		goto unlock;
-	}
-	clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
-	if (!irqchip_full(kvm))
-		goto unlock;
-
-	kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
-	kvm_pic_clear_all(kvm->arch.vpic, irq_source_id);
-unlock:
-	mutex_unlock(&kvm->irq_lock);
-}
-
 void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
 				    struct kvm_irq_mask_notifier *kimn)
 {
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 9461517b4e62..cba8fc4529e8 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1784,8 +1784,6 @@ void kvm_register_irq_ack_notifier(struct kvm *kvm,
 				   struct kvm_irq_ack_notifier *kian);
 void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
 				   struct kvm_irq_ack_notifier *kian);
-int kvm_request_irq_source_id(struct kvm *kvm);
-void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id);
 bool kvm_arch_irqfd_allowed(struct kvm *kvm, struct kvm_irqfd *args);
 
 /*
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 10/18] KVM: x86: Hardcode the PIT IRQ source ID to '2'

[Sean Christopherson]

Hardcode the PIT's source IRQ ID to '2' instead of "finding" that bit 2
is always the first available bit in irq_sources_bitmap.  Bits 0 and 1 are
set/reserved by kvm_arch_init_vm(), i.e. long before kvm_create_pit() can
be invoked, and KVM allows at most one in-kernel PIT instance, i.e. it's
impossible for the PIT to find a different free bit (there are no other
users of kvm_request_irq_source_id().

Delete the now-defunct irq_sources_bitmap and all its associated code.

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/include/asm/kvm_host.h |  1 -
 arch/x86/kvm/i8254.c            | 55 +++++----------------------------
 arch/x86/kvm/i8254.h            |  1 -
 arch/x86/kvm/x86.c              |  6 ----
 include/linux/kvm_host.h        |  1 +
 5 files changed, 8 insertions(+), 56 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f25ec3ec5ce4..c8654e461933 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1396,7 +1396,6 @@ struct kvm_arch {
 	bool pause_in_guest;
 	bool cstate_in_guest;
 
-	unsigned long irq_sources_bitmap;
 	s64 kvmclock_offset;
 
 	/*
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 2bb223bf0dac..fa8187608cfc 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -248,8 +248,8 @@ static void pit_do_work(struct kthread_work *work)
 	if (atomic_read(&ps->reinject) && !atomic_xchg(&ps->irq_ack, 0))
 		return;
 
-	kvm_set_irq(kvm, pit->irq_source_id, 0, 1, false);
-	kvm_set_irq(kvm, pit->irq_source_id, 0, 0, false);
+	kvm_set_irq(kvm, KVM_PIT_IRQ_SOURCE_ID, 0, 1, false);
+	kvm_set_irq(kvm, KVM_PIT_IRQ_SOURCE_ID, 0, 0, false);
 
 	/*
 	 * Provides NMI watchdog support via Virtual Wire mode.
@@ -641,47 +641,11 @@ static void kvm_pit_reset(struct kvm_pit *pit)
 	kvm_pit_reset_reinject(pit);
 }
 
-static int kvm_request_irq_source_id(struct kvm *kvm)
+static void kvm_pit_clear_all(struct kvm *kvm)
 {
-	unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
-	int irq_source_id;
-
 	mutex_lock(&kvm->irq_lock);
-	irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
-
-	if (irq_source_id >= BITS_PER_LONG) {
-		pr_warn("exhausted allocatable IRQ sources!\n");
-		irq_source_id = -EFAULT;
-		goto unlock;
-	}
-
-	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
-	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
-	set_bit(irq_source_id, bitmap);
-unlock:
-	mutex_unlock(&kvm->irq_lock);
-
-	return irq_source_id;
-}
-
-static void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
-{
-	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
-	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
-
-	mutex_lock(&kvm->irq_lock);
-	if (irq_source_id < 0 ||
-	    irq_source_id >= BITS_PER_LONG) {
-		pr_err("IRQ source ID out of range!\n");
-		goto unlock;
-	}
-	clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
-	if (!irqchip_full(kvm))
-		goto unlock;
-
-	kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
-	kvm_pic_clear_all(kvm->arch.vpic, irq_source_id);
-unlock:
+	kvm_ioapic_clear_all(kvm->arch.vioapic, KVM_PIT_IRQ_SOURCE_ID);
+	kvm_pic_clear_all(kvm->arch.vpic, KVM_PIT_IRQ_SOURCE_ID);
 	mutex_unlock(&kvm->irq_lock);
 }
 
@@ -788,10 +752,6 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
 	if (!pit)
 		return NULL;
 
-	pit->irq_source_id = kvm_request_irq_source_id(kvm);
-	if (pit->irq_source_id < 0)
-		goto fail_request;
-
 	mutex_init(&pit->pit_state.lock);
 
 	pid = get_pid(task_tgid(current));
@@ -843,8 +803,7 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
 	kvm_pit_set_reinject(pit, false);
 	kthread_destroy_worker(pit->worker);
 fail_kthread:
-	kvm_free_irq_source_id(kvm, pit->irq_source_id);
-fail_request:
+	kvm_pit_clear_all(kvm);
 	kfree(pit);
 	return NULL;
 }
@@ -861,7 +820,7 @@ void kvm_free_pit(struct kvm *kvm)
 		kvm_pit_set_reinject(pit, false);
 		hrtimer_cancel(&pit->pit_state.timer);
 		kthread_destroy_worker(pit->worker);
-		kvm_free_irq_source_id(kvm, pit->irq_source_id);
+		kvm_pit_clear_all(kvm);
 		kfree(pit);
 	}
 }
diff --git a/arch/x86/kvm/i8254.h b/arch/x86/kvm/i8254.h
index 338095829ec8..b9c1feb379a7 100644
--- a/arch/x86/kvm/i8254.h
+++ b/arch/x86/kvm/i8254.h
@@ -44,7 +44,6 @@ struct kvm_pit {
 	struct kvm_io_device speaker_dev;
 	struct kvm *kvm;
 	struct kvm_kpit_state pit_state;
-	int irq_source_id;
 	struct kvm_irq_mask_notifier mask_notifier;
 	struct kthread_worker *worker;
 	struct kthread_work expired;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f02a9a332f69..115405f496ef 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12669,12 +12669,6 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	INIT_HLIST_HEAD(&kvm->arch.mask_notifier_list);
 	atomic_set(&kvm->arch.noncoherent_dma_count, 0);
 
-	/* Reserve bit 0 of irq_sources_bitmap for userspace irq source */
-	set_bit(KVM_USERSPACE_IRQ_SOURCE_ID, &kvm->arch.irq_sources_bitmap);
-	/* Reserve bit 1 of irq_sources_bitmap for irqfd-resampler */
-	set_bit(KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID,
-		&kvm->arch.irq_sources_bitmap);
-
 	raw_spin_lock_init(&kvm->arch.tsc_write_lock);
 	mutex_init(&kvm->arch.apic_map_lock);
 	seqcount_raw_spinlock_init(&kvm->arch.pvclock_sc, &kvm->arch.tsc_write_lock);
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index cba8fc4529e8..4ff5ea29e343 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -190,6 +190,7 @@ bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req);
 
 #define KVM_USERSPACE_IRQ_SOURCE_ID		0
 #define KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID	1
+#define KVM_PIT_IRQ_SOURCE_ID			2
 
 extern struct mutex kvm_lock;
 extern struct list_head vm_list;
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 11/18] KVM: x86: Don't clear PIT's IRQ line status when destroying PIT

[Sean Christopherson]

Don't bother clearing the PIT's IRQ line status when destroying the PIT,
as userspace can't possibly rely on KVM to lower the IRQ line in any sane
use case, and it's not at all obvious that clearing the PIT's IRQ line is
correct/desirable in kvm_create_pit()'s error path.

When called from kvm_arch_pre_destroy_vm(), the entire VM is being torn
down and thus {kvm_pic,kvm_ioapic}.irq_states are unreachable.

As for the error path in kvm_create_pit(), the only way the PIT's bit in
irq_states can be set is if userspace raises the associated IRQ before
KVM_CREATE_PIT{2} completes.  Forcefully clearing the bit would clobber
userspace's input, nonsensical though that input may be.  Not to mention
that no known VMM will continue on if PIT creation fails.

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/include/asm/kvm_host.h |  2 --
 arch/x86/kvm/i8254.c            | 10 ----------
 arch/x86/kvm/i8259.c            | 10 ----------
 arch/x86/kvm/ioapic.c           | 10 ----------
 arch/x86/kvm/ioapic.h           |  1 -
 5 files changed, 33 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index c8654e461933..ebda93979179 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -2207,8 +2207,6 @@ static inline int __kvm_irq_line_state(unsigned long *irq_state,
 	return !!(*irq_state);
 }
 
-void kvm_pic_clear_all(struct kvm_pic *pic, int irq_source_id);
-
 void kvm_inject_nmi(struct kvm_vcpu *vcpu);
 int kvm_get_nr_pending_nmis(struct kvm_vcpu *vcpu);
 
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index fa8187608cfc..d1b79b418c05 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -641,14 +641,6 @@ static void kvm_pit_reset(struct kvm_pit *pit)
 	kvm_pit_reset_reinject(pit);
 }
 
-static void kvm_pit_clear_all(struct kvm *kvm)
-{
-	mutex_lock(&kvm->irq_lock);
-	kvm_ioapic_clear_all(kvm->arch.vioapic, KVM_PIT_IRQ_SOURCE_ID);
-	kvm_pic_clear_all(kvm->arch.vpic, KVM_PIT_IRQ_SOURCE_ID);
-	mutex_unlock(&kvm->irq_lock);
-}
-
 static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask)
 {
 	struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier);
@@ -803,7 +795,6 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
 	kvm_pit_set_reinject(pit, false);
 	kthread_destroy_worker(pit->worker);
 fail_kthread:
-	kvm_pit_clear_all(kvm);
 	kfree(pit);
 	return NULL;
 }
@@ -820,7 +811,6 @@ void kvm_free_pit(struct kvm *kvm)
 		kvm_pit_set_reinject(pit, false);
 		hrtimer_cancel(&pit->pit_state.timer);
 		kthread_destroy_worker(pit->worker);
-		kvm_pit_clear_all(kvm);
 		kfree(pit);
 	}
 }
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index 0150aec4f523..4de055efc4ee 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -206,16 +206,6 @@ int kvm_pic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
 	return ret;
 }
 
-void kvm_pic_clear_all(struct kvm_pic *s, int irq_source_id)
-{
-	int i;
-
-	pic_lock(s);
-	for (i = 0; i < PIC_NUM_PINS; i++)
-		__clear_bit(irq_source_id, &s->irq_states[i]);
-	pic_unlock(s);
-}
-
 /*
  * acknowledge interrupt 'irq'
  */
diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index 8c8a8062eb19..65626da1407f 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -498,16 +498,6 @@ int kvm_ioapic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
 	return ret;
 }
 
-void kvm_ioapic_clear_all(struct kvm_ioapic *ioapic, int irq_source_id)
-{
-	int i;
-
-	spin_lock(&ioapic->lock);
-	for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
-		__clear_bit(irq_source_id, &ioapic->irq_states[i]);
-	spin_unlock(&ioapic->lock);
-}
-
 static void kvm_ioapic_eoi_inject_work(struct work_struct *work)
 {
 	int i;
diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
index 289cca3aec69..dc92bd7c37bc 100644
--- a/arch/x86/kvm/ioapic.h
+++ b/arch/x86/kvm/ioapic.h
@@ -114,7 +114,6 @@ void kvm_ioapic_destroy(struct kvm *kvm);
 int kvm_ioapic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
 		       int irq_source_id, int level, bool line_status);
 
-void kvm_ioapic_clear_all(struct kvm_ioapic *ioapic, int irq_source_id);
 void kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
 void kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
 void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu,
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 12/18] KVM: x86: Explicitly check for in-kernel PIC when getting ExtINT

[Sean Christopherson]

Explicitly check for an in-kernel PIC when checking for a pending ExtINT
in the PIC.  Effectively swapping the split vs. full irqchip logic will
allow guarding the in-kernel I/O APIC (and PIC) emulation with a Kconfig,
and also makes it more obvious that kvm_pic_read_irq() won't result in a
NULL pointer dereference.

Opportunistically add WARNs in the fallthrough path, mostly to document
that the userspace ExtINT logic is only relevant to split IRQ chips.

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/irq.c | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index b696161ec078..fb3bad0f4965 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -42,6 +42,14 @@ static int pending_userspace_extint(struct kvm_vcpu *v)
 	return v->arch.pending_external_vector != -1;
 }
 
+static int get_userspace_extint(struct kvm_vcpu *vcpu)
+{
+	int vector = vcpu->arch.pending_external_vector;
+
+	vcpu->arch.pending_external_vector = -1;
+	return vector;
+}
+
 /*
  * check if there is pending interrupt from
  * non-APIC source without intack.
@@ -68,10 +76,11 @@ int kvm_cpu_has_extint(struct kvm_vcpu *v)
 	if (!kvm_apic_accept_pic_intr(v))
 		return 0;
 
-	if (irqchip_split(v->kvm))
-		return pending_userspace_extint(v);
-	else
+	if (pic_in_kernel(v->kvm))
 		return v->kvm->arch.vpic->output;
+
+	WARN_ON_ONCE(!irqchip_split(v->kvm));
+	return pending_userspace_extint(v);
 }
 
 /*
@@ -127,13 +136,11 @@ int kvm_cpu_get_extint(struct kvm_vcpu *v)
 		return v->kvm->arch.xen.upcall_vector;
 #endif
 
-	if (irqchip_split(v->kvm)) {
-		int vector = v->arch.pending_external_vector;
-
-		v->arch.pending_external_vector = -1;
-		return vector;
-	} else
+	if (pic_in_kernel(v->kvm))
 		return kvm_pic_read_irq(v->kvm); /* PIC */
+
+	WARN_ON_ONCE(!irqchip_split(v->kvm));
+	return get_userspace_extint(v);
 }
 EXPORT_SYMBOL_GPL(kvm_cpu_get_extint);
 
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 13/18] KVM: Move x86-only tracepoints to x86's trace.h

[Sean Christopherson]

Move the I/O APIC tracepoints and trace_kvm_msi_set_irq() to x86, as
__KVM_HAVE_IOAPIC is just code for "x86", and trace_kvm_msi_set_irq()
isn't unique to I/O APIC emulation.

Opportunistically clean up the absurdly messy #includes in ioapic.c.

No functional change intended.

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/ioapic.c      |  2 +-
 arch/x86/kvm/irq_comm.c    | 10 ++---
 arch/x86/kvm/trace.h       | 78 ++++++++++++++++++++++++++++++++++++++
 include/trace/events/kvm.h | 77 -------------------------------------
 4 files changed, 82 insertions(+), 85 deletions(-)

diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index 65626da1407f..fa7481814bc6 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -41,11 +41,11 @@
 #include <asm/processor.h>
 #include <asm/page.h>
 #include <asm/current.h>
-#include <trace/events/kvm.h>
 
 #include "ioapic.h"
 #include "lapic.h"
 #include "irq.h"
+#include "trace.h"
 
 static int ioapic_service(struct kvm_ioapic *vioapic, int irq,
 		bool line_status);
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index 138c675dc24b..13d84c25e503 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -15,15 +15,11 @@
 #include <linux/export.h>
 #include <linux/rculist.h>
 
-#include <trace/events/kvm.h>
-
-#include "irq.h"
-
+#include "hyperv.h"
 #include "ioapic.h"
-
+#include "irq.h"
 #include "lapic.h"
-
-#include "hyperv.h"
+#include "trace.h"
 #include "x86.h"
 #include "xen.h"
 
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index ba736cbb0587..4ef17990574d 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -260,6 +260,84 @@ TRACE_EVENT(kvm_cpuid,
 		  __entry->used_max_basic ? ", used max basic" : "")
 );
 
+#define kvm_deliver_mode		\
+	{0x0, "Fixed"},			\
+	{0x1, "LowPrio"},		\
+	{0x2, "SMI"},			\
+	{0x3, "Res3"},			\
+	{0x4, "NMI"},			\
+	{0x5, "INIT"},			\
+	{0x6, "SIPI"},			\
+	{0x7, "ExtINT"}
+
+TRACE_EVENT(kvm_ioapic_set_irq,
+	    TP_PROTO(__u64 e, int pin, bool coalesced),
+	    TP_ARGS(e, pin, coalesced),
+
+	TP_STRUCT__entry(
+		__field(	__u64,		e		)
+		__field(	int,		pin		)
+		__field(	bool,		coalesced	)
+	),
+
+	TP_fast_assign(
+		__entry->e		= e;
+		__entry->pin		= pin;
+		__entry->coalesced	= coalesced;
+	),
+
+	TP_printk("pin %u dst %x vec %u (%s|%s|%s%s)%s",
+		  __entry->pin, (u8)(__entry->e >> 56), (u8)__entry->e,
+		  __print_symbolic((__entry->e >> 8 & 0x7), kvm_deliver_mode),
+		  (__entry->e & (1<<11)) ? "logical" : "physical",
+		  (__entry->e & (1<<15)) ? "level" : "edge",
+		  (__entry->e & (1<<16)) ? "|masked" : "",
+		  __entry->coalesced ? " (coalesced)" : "")
+);
+
+TRACE_EVENT(kvm_ioapic_delayed_eoi_inj,
+	    TP_PROTO(__u64 e),
+	    TP_ARGS(e),
+
+	TP_STRUCT__entry(
+		__field(	__u64,		e		)
+	),
+
+	TP_fast_assign(
+		__entry->e		= e;
+	),
+
+	TP_printk("dst %x vec %u (%s|%s|%s%s)",
+		  (u8)(__entry->e >> 56), (u8)__entry->e,
+		  __print_symbolic((__entry->e >> 8 & 0x7), kvm_deliver_mode),
+		  (__entry->e & (1<<11)) ? "logical" : "physical",
+		  (__entry->e & (1<<15)) ? "level" : "edge",
+		  (__entry->e & (1<<16)) ? "|masked" : "")
+);
+
+TRACE_EVENT(kvm_msi_set_irq,
+	    TP_PROTO(__u64 address, __u64 data),
+	    TP_ARGS(address, data),
+
+	TP_STRUCT__entry(
+		__field(	__u64,		address		)
+		__field(	__u64,		data		)
+	),
+
+	TP_fast_assign(
+		__entry->address	= address;
+		__entry->data		= data;
+	),
+
+	TP_printk("dst %llx vec %u (%s|%s|%s%s)",
+		  (u8)(__entry->address >> 12) | ((__entry->address >> 32) & 0xffffff00),
+		  (u8)__entry->data,
+		  __print_symbolic((__entry->data >> 8 & 0x7), kvm_deliver_mode),
+		  (__entry->address & (1<<2)) ? "logical" : "physical",
+		  (__entry->data & (1<<15)) ? "level" : "edge",
+		  (__entry->address & (1<<3)) ? "|rh" : "")
+);
+
 #define AREG(x) { APIC_##x, "APIC_" #x }
 
 #define kvm_trace_symbol_apic						    \
diff --git a/include/trace/events/kvm.h b/include/trace/events/kvm.h
index fc7d0f8ff078..96e581900c8e 100644
--- a/include/trace/events/kvm.h
+++ b/include/trace/events/kvm.h
@@ -85,83 +85,6 @@ TRACE_EVENT(kvm_set_irq,
 #endif /* defined(CONFIG_HAVE_KVM_IRQCHIP) */
 
 #if defined(__KVM_HAVE_IOAPIC)
-#define kvm_deliver_mode		\
-	{0x0, "Fixed"},			\
-	{0x1, "LowPrio"},		\
-	{0x2, "SMI"},			\
-	{0x3, "Res3"},			\
-	{0x4, "NMI"},			\
-	{0x5, "INIT"},			\
-	{0x6, "SIPI"},			\
-	{0x7, "ExtINT"}
-
-TRACE_EVENT(kvm_ioapic_set_irq,
-	    TP_PROTO(__u64 e, int pin, bool coalesced),
-	    TP_ARGS(e, pin, coalesced),
-
-	TP_STRUCT__entry(
-		__field(	__u64,		e		)
-		__field(	int,		pin		)
-		__field(	bool,		coalesced	)
-	),
-
-	TP_fast_assign(
-		__entry->e		= e;
-		__entry->pin		= pin;
-		__entry->coalesced	= coalesced;
-	),
-
-	TP_printk("pin %u dst %x vec %u (%s|%s|%s%s)%s",
-		  __entry->pin, (u8)(__entry->e >> 56), (u8)__entry->e,
-		  __print_symbolic((__entry->e >> 8 & 0x7), kvm_deliver_mode),
-		  (__entry->e & (1<<11)) ? "logical" : "physical",
-		  (__entry->e & (1<<15)) ? "level" : "edge",
-		  (__entry->e & (1<<16)) ? "|masked" : "",
-		  __entry->coalesced ? " (coalesced)" : "")
-);
-
-TRACE_EVENT(kvm_ioapic_delayed_eoi_inj,
-	    TP_PROTO(__u64 e),
-	    TP_ARGS(e),
-
-	TP_STRUCT__entry(
-		__field(	__u64,		e		)
-	),
-
-	TP_fast_assign(
-		__entry->e		= e;
-	),
-
-	TP_printk("dst %x vec %u (%s|%s|%s%s)",
-		  (u8)(__entry->e >> 56), (u8)__entry->e,
-		  __print_symbolic((__entry->e >> 8 & 0x7), kvm_deliver_mode),
-		  (__entry->e & (1<<11)) ? "logical" : "physical",
-		  (__entry->e & (1<<15)) ? "level" : "edge",
-		  (__entry->e & (1<<16)) ? "|masked" : "")
-);
-
-TRACE_EVENT(kvm_msi_set_irq,
-	    TP_PROTO(__u64 address, __u64 data),
-	    TP_ARGS(address, data),
-
-	TP_STRUCT__entry(
-		__field(	__u64,		address		)
-		__field(	__u64,		data		)
-	),
-
-	TP_fast_assign(
-		__entry->address	= address;
-		__entry->data		= data;
-	),
-
-	TP_printk("dst %llx vec %u (%s|%s|%s%s)",
-		  (u8)(__entry->address >> 12) | ((__entry->address >> 32) & 0xffffff00),
-		  (u8)__entry->data,
-		  __print_symbolic((__entry->data >> 8 & 0x7), kvm_deliver_mode),
-		  (__entry->address & (1<<2)) ? "logical" : "physical",
-		  (__entry->data & (1<<15)) ? "level" : "edge",
-		  (__entry->address & (1<<3)) ? "|rh" : "")
-);
 
 #define kvm_irqchips						\
 	{KVM_IRQCHIP_PIC_MASTER,	"PIC master"},		\
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 14/18] KVM: x86: Add CONFIG_KVM_IOAPIC to allow disabling in-kernel I/O APIC

[Sean Christopherson]

Add a Kconfig to allow building KVM without support for emulating a I/O
APIC, PIC, and PIT, which is desirable for deployments that effectively
don't support a fully in-kernel IRQ chip, i.e. never expect any VMM to
create an in-kernel I/O APIC.  E.g. compiling out support eliminates a few
thousand lines of guest-facing code and gives security folks warm fuzzies.

As a bonus, wrapping relevant paths with CONFIG_KVM_IOAPIC #ifdefs makes
it much easier for readers to understand which bits and pieces exist
specifically for fully in-kernel IRQ chips.

Opportunistically convert all two in-kernel uses of __KVM_HAVE_IOAPIC to
CONFIG_KVM_IOAPIC, e.g. rather than add a second #ifdef to generate a stub
for kvm_arch_post_irq_routing_update().

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/include/asm/kvm_host.h |  2 ++
 arch/x86/kvm/Kconfig            | 10 ++++++++++
 arch/x86/kvm/Makefile           |  5 +++--
 arch/x86/kvm/i8254.h            |  2 ++
 arch/x86/kvm/irq.c              |  8 ++++++++
 arch/x86/kvm/irq.h              |  9 +++++++++
 arch/x86/kvm/irq_comm.c         |  2 ++
 arch/x86/kvm/lapic.c            |  7 ++++++-
 arch/x86/kvm/trace.h            |  2 ++
 arch/x86/kvm/x86.c              | 22 ++++++++++++++++++----
 include/linux/kvm_host.h        |  2 +-
 include/trace/events/kvm.h      |  4 ++--
 12 files changed, 65 insertions(+), 10 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index ebda93979179..f5ff5174674c 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1374,9 +1374,11 @@ struct kvm_arch {
 	atomic_t noncoherent_dma_count;
 #define __KVM_HAVE_ARCH_ASSIGNED_DEVICE
 	atomic_t assigned_device_count;
+#ifdef CONFIG_KVM_IOAPIC
 	struct kvm_pic *vpic;
 	struct kvm_ioapic *vioapic;
 	struct kvm_pit *vpit;
+#endif
 	atomic_t vapics_in_nmi_mode;
 	struct mutex apic_map_lock;
 	struct kvm_apic_map __rcu *apic_map;
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 2eeffcec5382..2c86673155c9 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -166,6 +166,16 @@ config KVM_AMD_SEV
 	  Encrypted State (SEV-ES), and Secure Encrypted Virtualization with
 	  Secure Nested Paging (SEV-SNP) technologies on AMD processors.
 
+config KVM_IOAPIC
+	bool "I/O APIC, PIC, and PIT emulation"
+	default y
+	depends on KVM
+	help
+	  Provides support for KVM to emulate an I/O APIC, PIC, and PIT, i.e.
+	  for full in-kernel APIC emulation.
+
+	  If unsure, say Y.
+
 config KVM_SMM
 	bool "System Management Mode emulation"
 	default y
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index a5d362c7b504..92c737257789 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -5,12 +5,13 @@ ccflags-$(CONFIG_KVM_WERROR) += -Werror
 
 include $(srctree)/virt/kvm/Makefile.kvm
 
-kvm-y			+= x86.o emulate.o i8259.o irq.o lapic.o \
-			   i8254.o ioapic.o irq_comm.o cpuid.o pmu.o mtrr.o \
+kvm-y			+= x86.o emulate.o irq.o lapic.o \
+			   irq_comm.o cpuid.o pmu.o mtrr.o \
 			   debugfs.o mmu/mmu.o mmu/page_track.o \
 			   mmu/spte.o
 
 kvm-$(CONFIG_X86_64) += mmu/tdp_iter.o mmu/tdp_mmu.o
+kvm-$(CONFIG_KVM_IOAPIC) += i8259.o i8254.o ioapic.o
 kvm-$(CONFIG_KVM_HYPERV) += hyperv.o
 kvm-$(CONFIG_KVM_XEN)	+= xen.o
 kvm-$(CONFIG_KVM_SMM)	+= smm.o
diff --git a/arch/x86/kvm/i8254.h b/arch/x86/kvm/i8254.h
index b9c1feb379a7..e8bd59ad8a7c 100644
--- a/arch/x86/kvm/i8254.h
+++ b/arch/x86/kvm/i8254.h
@@ -8,6 +8,7 @@
 
 #include <uapi/asm/kvm.h>
 
+#ifdef CONFIG_KVM_IOAPIC
 struct kvm_kpit_channel_state {
 	u32 count; /* can be 65536 */
 	u16 latched_count;
@@ -64,5 +65,6 @@ int kvm_vm_ioctl_reinject(struct kvm *kvm, struct kvm_reinject_control *control)
 
 struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags);
 void kvm_free_pit(struct kvm *kvm);
+#endif /* CONFIG_KVM_IOAPIC */
 
 #endif
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index fb3bad0f4965..4c219e9f52b0 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -76,8 +76,10 @@ int kvm_cpu_has_extint(struct kvm_vcpu *v)
 	if (!kvm_apic_accept_pic_intr(v))
 		return 0;
 
+#ifdef CONFIG_KVM_IOAPIC
 	if (pic_in_kernel(v->kvm))
 		return v->kvm->arch.vpic->output;
+#endif
 
 	WARN_ON_ONCE(!irqchip_split(v->kvm));
 	return pending_userspace_extint(v);
@@ -136,8 +138,10 @@ int kvm_cpu_get_extint(struct kvm_vcpu *v)
 		return v->kvm->arch.xen.upcall_vector;
 #endif
 
+#ifdef CONFIG_KVM_IOAPIC
 	if (pic_in_kernel(v->kvm))
 		return kvm_pic_read_irq(v->kvm); /* PIC */
+#endif
 
 	WARN_ON_ONCE(!irqchip_split(v->kvm));
 	return get_userspace_extint(v);
@@ -171,7 +175,9 @@ void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
 void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
 {
 	__kvm_migrate_apic_timer(vcpu);
+#ifdef CONFIG_KVM_IOAPIC
 	__kvm_migrate_pit_timer(vcpu);
+#endif
 	kvm_x86_call(migrate_timers)(vcpu);
 }
 
@@ -187,6 +193,7 @@ bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
 	return irqchip_in_kernel(kvm);
 }
 
+#ifdef CONFIG_KVM_IOAPIC
 #define IOAPIC_ROUTING_ENTRY(irq) \
 	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
 	  .u.irqchip = { .irqchip = KVM_IRQCHIP_IOAPIC, .pin = (irq) } }
@@ -273,3 +280,4 @@ int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
 	kvm_pic_update_irq(pic);
 	return r;
 }
+#endif
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 7b8b54462f95..5e62c1f79ce6 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -18,6 +18,8 @@
 #include <kvm/iodev.h>
 #include "lapic.h"
 
+#ifdef CONFIG_KVM_IOAPIC
+
 #define PIC_NUM_PINS 16
 #define SELECT_PIC(irq) \
 	((irq) < 8 ? KVM_IRQCHIP_PIC_MASTER : KVM_IRQCHIP_PIC_SLAVE)
@@ -79,12 +81,19 @@ static inline int irqchip_full(struct kvm *kvm)
 	smp_rmb();
 	return mode == KVM_IRQCHIP_KERNEL;
 }
+#else /* CONFIG_KVM_IOAPIC */
+static __always_inline int irqchip_full(struct kvm *kvm)
+{
+	return false;
+}
+#endif
 
 static inline int pic_in_kernel(struct kvm *kvm)
 {
 	return irqchip_full(kvm);
 }
 
+
 static inline int irqchip_split(struct kvm *kvm)
 {
 	int mode = kvm->arch.irqchip_mode;
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index 13d84c25e503..14fc8db0206c 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -208,6 +208,7 @@ int kvm_set_routing_entry(struct kvm *kvm,
 	 * check kvm_arch_can_set_irq_routing() before calling this function.
 	 */
 	switch (ue->type) {
+#ifdef CONFIG_KVM_IOAPIC
 	case KVM_IRQ_ROUTING_IRQCHIP:
 		if (irqchip_split(kvm))
 			return -EINVAL;
@@ -231,6 +232,7 @@ int kvm_set_routing_entry(struct kvm *kvm,
 		}
 		e->irqchip.irqchip = ue->u.irqchip.irqchip;
 		break;
+#endif
 	case KVM_IRQ_ROUTING_MSI:
 		e->set = kvm_set_msi;
 		e->msi.address_lo = ue->u.msi.address_lo;
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 73418dc0ebb2..4cf8c1f753d3 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1455,7 +1455,7 @@ static bool kvm_ioapic_handles_vector(struct kvm_lapic *apic, int vector)
 
 static void kvm_ioapic_send_eoi(struct kvm_lapic *apic, int vector)
 {
-	int trigger_mode;
+	int __maybe_unused trigger_mode;
 
 	/* Eoi the ioapic only if the ioapic doesn't own the vector. */
 	if (!kvm_ioapic_handles_vector(apic, vector))
@@ -1476,12 +1476,14 @@ static void kvm_ioapic_send_eoi(struct kvm_lapic *apic, int vector)
 		return;
 	}
 
+#ifdef CONFIG_KVM_IOAPIC
 	if (apic_test_vector(vector, apic->regs + APIC_TMR))
 		trigger_mode = IOAPIC_LEVEL_TRIG;
 	else
 		trigger_mode = IOAPIC_EDGE_TRIG;
 
 	kvm_ioapic_update_eoi(apic->vcpu, vector, trigger_mode);
+#endif
 }
 
 static int apic_set_eoi(struct kvm_lapic *apic)
@@ -3146,8 +3148,11 @@ int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s)
 		kvm_x86_call(hwapic_isr_update)(vcpu, apic_find_highest_isr(apic));
 	}
 	kvm_make_request(KVM_REQ_EVENT, vcpu);
+
+#ifdef CONFIG_KVM_IOAPIC
 	if (ioapic_in_kernel(vcpu->kvm))
 		kvm_rtc_eoi_tracking_restore_one(vcpu);
+#endif
 
 	vcpu->arch.apic_arb_prio = 0;
 
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index 4ef17990574d..ababdba2c186 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -270,6 +270,7 @@ TRACE_EVENT(kvm_cpuid,
 	{0x6, "SIPI"},			\
 	{0x7, "ExtINT"}
 
+#ifdef CONFIG_KVM_IOAPIC
 TRACE_EVENT(kvm_ioapic_set_irq,
 	    TP_PROTO(__u64 e, int pin, bool coalesced),
 	    TP_ARGS(e, pin, coalesced),
@@ -314,6 +315,7 @@ TRACE_EVENT(kvm_ioapic_delayed_eoi_inj,
 		  (__entry->e & (1<<15)) ? "level" : "edge",
 		  (__entry->e & (1<<16)) ? "|masked" : "")
 );
+#endif
 
 TRACE_EVENT(kvm_msi_set_irq,
 	    TP_PROTO(__u64 address, __u64 data),
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 115405f496ef..a39babc32a6a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4632,17 +4632,20 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_EXT_CPUID:
 	case KVM_CAP_EXT_EMUL_CPUID:
 	case KVM_CAP_CLOCKSOURCE:
+#ifdef CONFIG_KVM_IOAPIC
 	case KVM_CAP_PIT:
+	case KVM_CAP_PIT2:
+	case KVM_CAP_PIT_STATE2:
+	case KVM_CAP_REINJECT_CONTROL:
+#endif
 	case KVM_CAP_NOP_IO_DELAY:
 	case KVM_CAP_MP_STATE:
 	case KVM_CAP_SYNC_MMU:
 	case KVM_CAP_USER_NMI:
-	case KVM_CAP_REINJECT_CONTROL:
 	case KVM_CAP_IRQ_INJECT_STATUS:
 	case KVM_CAP_IOEVENTFD:
 	case KVM_CAP_IOEVENTFD_NO_LENGTH:
-	case KVM_CAP_PIT2:
-	case KVM_CAP_PIT_STATE2:
+
 	case KVM_CAP_SET_IDENTITY_MAP_ADDR:
 	case KVM_CAP_VCPU_EVENTS:
 #ifdef CONFIG_KVM_HYPERV
@@ -6937,9 +6940,11 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 	struct kvm *kvm = filp->private_data;
 	void __user *argp = (void __user *)arg;
 	int r = -ENOTTY;
+
+#ifdef CONFIG_KVM_IOAPIC
 	/*
 	 * This union makes it completely explicit to gcc-3.x
-	 * that these two variables' stack usage should be
+	 * that these three variables' stack usage should be
 	 * combined, not added together.
 	 */
 	union {
@@ -6947,6 +6952,7 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 		struct kvm_pit_state2 ps2;
 		struct kvm_pit_config pit_config;
 	} u;
+#endif
 
 	switch (ioctl) {
 	case KVM_SET_TSS_ADDR:
@@ -6970,6 +6976,7 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 	case KVM_SET_NR_MMU_PAGES:
 		r = kvm_vm_ioctl_set_nr_mmu_pages(kvm, arg);
 		break;
+#ifdef CONFIG_KVM_IOAPIC
 	case KVM_CREATE_IRQCHIP: {
 		mutex_lock(&kvm->lock);
 
@@ -7136,6 +7143,7 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 		r = kvm_vm_ioctl_reinject(kvm, &control);
 		break;
 	}
+#endif
 	case KVM_SET_BOOT_CPU_ID:
 		r = 0;
 		mutex_lock(&kvm->lock);
@@ -10595,8 +10603,10 @@ static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu)
 
 	if (irqchip_split(vcpu->kvm))
 		kvm_scan_ioapic_routes(vcpu, vcpu->arch.ioapic_handled_vectors);
+#ifdef CONFIG_KVM_IOAPIC
 	else if (ioapic_in_kernel(vcpu->kvm))
 		kvm_ioapic_scan_entry(vcpu, vcpu->arch.ioapic_handled_vectors);
+#endif
 
 	if (is_guest_mode(vcpu))
 		vcpu->arch.load_eoi_exitmap_pending = true;
@@ -12799,7 +12809,9 @@ void kvm_arch_pre_destroy_vm(struct kvm *kvm)
 	cancel_delayed_work_sync(&kvm->arch.kvmclock_sync_work);
 	cancel_delayed_work_sync(&kvm->arch.kvmclock_update_work);
 
+#ifdef CONFIG_KVM_IOAPIC
 	kvm_free_pit(kvm);
+#endif
 
 	kvm_mmu_pre_destroy_vm(kvm);
 	static_call_cond(kvm_x86_vm_pre_destroy)(kvm);
@@ -12823,8 +12835,10 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
 	}
 	kvm_destroy_vcpus(kvm);
 	kvm_free_msr_filter(srcu_dereference_check(kvm->arch.msr_filter, &kvm->srcu, 1));
+#ifdef CONFIG_KVM_IOAPIC
 	kvm_pic_destroy(kvm);
 	kvm_ioapic_destroy(kvm);
+#endif
 	kvfree(rcu_dereference_check(kvm->arch.apic_map, 1));
 	kfree(srcu_dereference_check(kvm->arch.pmu_event_filter, &kvm->srcu, 1));
 	kvm_mmu_uninit_vm(kvm);
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 4ff5ea29e343..3b5575d0b574 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1023,7 +1023,7 @@ void kvm_unlock_all_vcpus(struct kvm *kvm);
 void vcpu_load(struct kvm_vcpu *vcpu);
 void vcpu_put(struct kvm_vcpu *vcpu);
 
-#ifdef __KVM_HAVE_IOAPIC
+#ifdef CONFIG_KVM_IOAPIC
 void kvm_arch_post_irq_ack_notifier_list_update(struct kvm *kvm);
 #else
 static inline void kvm_arch_post_irq_ack_notifier_list_update(struct kvm *kvm)
diff --git a/include/trace/events/kvm.h b/include/trace/events/kvm.h
index 96e581900c8e..1065a81ca57f 100644
--- a/include/trace/events/kvm.h
+++ b/include/trace/events/kvm.h
@@ -84,14 +84,14 @@ TRACE_EVENT(kvm_set_irq,
 );
 #endif /* defined(CONFIG_HAVE_KVM_IRQCHIP) */
 
-#if defined(__KVM_HAVE_IOAPIC)
+#ifdef CONFIG_KVM_IOAPIC
 
 #define kvm_irqchips						\
 	{KVM_IRQCHIP_PIC_MASTER,	"PIC master"},		\
 	{KVM_IRQCHIP_PIC_SLAVE,		"PIC slave"},		\
 	{KVM_IRQCHIP_IOAPIC,		"IOAPIC"}
 
-#endif /* defined(__KVM_HAVE_IOAPIC) */
+#endif /* CONFIG_KVM_IOAPIC */
 
 #if defined(CONFIG_HAVE_KVM_IRQCHIP)
 
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 15/18] KVM: Squash two CONFIG_HAVE_KVM_IRQCHIP #ifdefs into one

[Sean Christopherson]

Squash two #idef CONFIG_HAVE_KVM_IRQCHIP regions in KVM's trace events, as
the only code outside of the #idefs depends on CONFIG_KVM_IOAPIC, and that
Kconfig only exists for x86, which unconditionally selects HAVE_KVM_IRQCHIP.

No functional change intended.

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 include/trace/events/kvm.h | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/include/trace/events/kvm.h b/include/trace/events/kvm.h
index 1065a81ca57f..0b6b79b1a1bc 100644
--- a/include/trace/events/kvm.h
+++ b/include/trace/events/kvm.h
@@ -82,7 +82,6 @@ TRACE_EVENT(kvm_set_irq,
 	TP_printk("gsi %u level %d source %d",
 		  __entry->gsi, __entry->level, __entry->irq_source_id)
 );
-#endif /* defined(CONFIG_HAVE_KVM_IRQCHIP) */
 
 #ifdef CONFIG_KVM_IOAPIC
 
@@ -93,8 +92,6 @@ TRACE_EVENT(kvm_set_irq,
 
 #endif /* CONFIG_KVM_IOAPIC */
 
-#if defined(CONFIG_HAVE_KVM_IRQCHIP)
-
 #ifdef kvm_irqchips
 #define kvm_ack_irq_string "irqchip %s pin %u"
 #define kvm_ack_irq_parm  __print_symbolic(__entry->irqchip, kvm_irqchips), __entry->pin
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 16/18] KVM: selftests: Fall back to split IRQ chip if full in-kernel chip is unsupported

[Sean Christopherson]

Now that KVM x86 allows compiling out support for in-kernel I/O APIC (and
PIC and PIT) emulation, i.e. allows disabling KVM_CREATE_IRQCHIP for all
intents and purposes, fall back to a split IRQ chip for x86 if creating
the full in-kernel version fails with ENOTTY.

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 tools/testing/selftests/kvm/lib/kvm_util.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index a055343a7bf7..93a921deeb99 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1716,7 +1716,18 @@ void *addr_gpa2alias(struct kvm_vm *vm, vm_paddr_t gpa)
 /* Create an interrupt controller chip for the specified VM. */
 void vm_create_irqchip(struct kvm_vm *vm)
 {
-	vm_ioctl(vm, KVM_CREATE_IRQCHIP, NULL);
+	int r;
+
+	/*
+	 * Allocate a fully in-kernel IRQ chip by default, but fall back to a
+	 * split model (x86 only) if that fails (KVM x86 allows compiling out
+	 * support for KVM_CREATE_IRQCHIP).
+	 */
+	r = __vm_ioctl(vm, KVM_CREATE_IRQCHIP, NULL);
+	if (r && errno == ENOTTY && kvm_has_cap(KVM_CAP_SPLIT_IRQCHIP))
+		vm_enable_cap(vm, KVM_CAP_SPLIT_IRQCHIP, 24);
+	else
+		TEST_ASSERT_VM_VCPU_IOCTL(!r, KVM_CREATE_IRQCHIP, r, vm);
 
 	vm->has_irqchip = true;
 }
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 17/18] KVM: x86: Move IRQ mask notifier infrastructure to I/O APIC emulation

[Sean Christopherson]

Move the IRQ mask logic to ioapic.c as KVM's only user is its in-kernel
I/O APIC emulation.  In addition to encapsulating more I/O APIC specific
code, trimming down irq_comm.c helps pave the way for removing it entirely.

Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/include/asm/kvm_host.h | 16 --------------
 arch/x86/kvm/i8254.h            |  2 ++
 arch/x86/kvm/i8259.c            |  2 ++
 arch/x86/kvm/ioapic.c           | 37 +++++++++++++++++++++++++++++++++
 arch/x86/kvm/ioapic.h           | 16 ++++++++++++++
 arch/x86/kvm/irq_comm.c         | 33 -----------------------------
 arch/x86/kvm/x86.c              |  1 -
 7 files changed, 57 insertions(+), 50 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f5ff5174674c..21ccb122ab76 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1426,9 +1426,6 @@ struct kvm_arch {
 	struct delayed_work kvmclock_update_work;
 	struct delayed_work kvmclock_sync_work;
 
-	/* reads protected by irq_srcu, writes by irq_lock */
-	struct hlist_head mask_notifier_list;
-
 #ifdef CONFIG_KVM_HYPERV
 	struct kvm_hv hyperv;
 #endif
@@ -2038,19 +2035,6 @@ int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3);
 int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa,
 			  const void *val, int bytes);
 
-struct kvm_irq_mask_notifier {
-	void (*func)(struct kvm_irq_mask_notifier *kimn, bool masked);
-	int irq;
-	struct hlist_node link;
-};
-
-void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
-				    struct kvm_irq_mask_notifier *kimn);
-void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
-				      struct kvm_irq_mask_notifier *kimn);
-void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
-			     bool mask);
-
 extern bool tdp_enabled;
 
 u64 vcpu_tsc_khz(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/i8254.h b/arch/x86/kvm/i8254.h
index e8bd59ad8a7c..60fa499d2f8a 100644
--- a/arch/x86/kvm/i8254.h
+++ b/arch/x86/kvm/i8254.h
@@ -8,6 +8,8 @@
 
 #include <uapi/asm/kvm.h>
 
+#include "ioapic.h"
+
 #ifdef CONFIG_KVM_IOAPIC
 struct kvm_kpit_channel_state {
 	u32 count; /* can be 65536 */
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index 4de055efc4ee..2ac7f1678c46 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -31,6 +31,8 @@
 #include <linux/mm.h>
 #include <linux/slab.h>
 #include <linux/bitops.h>
+
+#include "ioapic.h"
 #include "irq.h"
 
 #include <linux/kvm_host.h>
diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index fa7481814bc6..2b5d389bca5f 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -310,6 +310,42 @@ void kvm_arch_post_irq_ack_notifier_list_update(struct kvm *kvm)
 	kvm_make_scan_ioapic_request(kvm);
 }
 
+void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
+				    struct kvm_irq_mask_notifier *kimn)
+{
+	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
+
+	mutex_lock(&kvm->irq_lock);
+	kimn->irq = irq;
+	hlist_add_head_rcu(&kimn->link, &ioapic->mask_notifier_list);
+	mutex_unlock(&kvm->irq_lock);
+}
+
+void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
+				      struct kvm_irq_mask_notifier *kimn)
+{
+	mutex_lock(&kvm->irq_lock);
+	hlist_del_rcu(&kimn->link);
+	mutex_unlock(&kvm->irq_lock);
+	synchronize_srcu(&kvm->irq_srcu);
+}
+
+void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
+			     bool mask)
+{
+	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
+	struct kvm_irq_mask_notifier *kimn;
+	int idx, gsi;
+
+	idx = srcu_read_lock(&kvm->irq_srcu);
+	gsi = kvm_irq_map_chip_pin(kvm, irqchip, pin);
+	if (gsi != -1)
+		hlist_for_each_entry_rcu(kimn, &ioapic->mask_notifier_list, link)
+			if (kimn->irq == gsi)
+				kimn->func(kimn, mask);
+	srcu_read_unlock(&kvm->irq_srcu, idx);
+}
+
 static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
 {
 	unsigned index;
@@ -710,6 +746,7 @@ int kvm_ioapic_init(struct kvm *kvm)
 		return -ENOMEM;
 	spin_lock_init(&ioapic->lock);
 	INIT_DELAYED_WORK(&ioapic->eoi_inject, kvm_ioapic_eoi_inject_work);
+	INIT_HLIST_HEAD(&ioapic->mask_notifier_list);
 	kvm->arch.vioapic = ioapic;
 	kvm_ioapic_reset(ioapic);
 	kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops);
diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
index dc92bd7c37bc..bf28dbc11ff6 100644
--- a/arch/x86/kvm/ioapic.h
+++ b/arch/x86/kvm/ioapic.h
@@ -86,8 +86,24 @@ struct kvm_ioapic {
 	struct delayed_work eoi_inject;
 	u32 irq_eoi[IOAPIC_NUM_PINS];
 	u32 irr_delivered;
+
+	/* reads protected by irq_srcu, writes by irq_lock */
+	struct hlist_head mask_notifier_list;
 };
 
+struct kvm_irq_mask_notifier {
+	void (*func)(struct kvm_irq_mask_notifier *kimn, bool masked);
+	int irq;
+	struct hlist_node link;
+};
+
+void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
+				    struct kvm_irq_mask_notifier *kimn);
+void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
+				      struct kvm_irq_mask_notifier *kimn);
+void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
+			     bool mask);
+
 #ifdef DEBUG
 #define ASSERT(x)  							\
 do {									\
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index 14fc8db0206c..76d1c85a1011 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -161,39 +161,6 @@ int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
 	return -EWOULDBLOCK;
 }
 
-void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
-				    struct kvm_irq_mask_notifier *kimn)
-{
-	mutex_lock(&kvm->irq_lock);
-	kimn->irq = irq;
-	hlist_add_head_rcu(&kimn->link, &kvm->arch.mask_notifier_list);
-	mutex_unlock(&kvm->irq_lock);
-}
-
-void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
-				      struct kvm_irq_mask_notifier *kimn)
-{
-	mutex_lock(&kvm->irq_lock);
-	hlist_del_rcu(&kimn->link);
-	mutex_unlock(&kvm->irq_lock);
-	synchronize_srcu(&kvm->irq_srcu);
-}
-
-void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
-			     bool mask)
-{
-	struct kvm_irq_mask_notifier *kimn;
-	int idx, gsi;
-
-	idx = srcu_read_lock(&kvm->irq_srcu);
-	gsi = kvm_irq_map_chip_pin(kvm, irqchip, pin);
-	if (gsi != -1)
-		hlist_for_each_entry_rcu(kimn, &kvm->arch.mask_notifier_list, link)
-			if (kimn->irq == gsi)
-				kimn->func(kimn, mask);
-	srcu_read_unlock(&kvm->irq_srcu, idx);
-}
-
 bool kvm_arch_can_set_irq_routing(struct kvm *kvm)
 {
 	return irqchip_in_kernel(kvm);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a39babc32a6a..28a20f0aa3dd 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12676,7 +12676,6 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	if (ret)
 		goto out_uninit_mmu;
 
-	INIT_HLIST_HEAD(&kvm->arch.mask_notifier_list);
 	atomic_set(&kvm->arch.noncoherent_dma_count, 0);
 
 	raw_spin_lock_init(&kvm->arch.tsc_write_lock);
-- 
2.50.0.rc1.591.g9c95f17f64-goog

[PATCH v2 18/18] KVM: x86: Fold irq_comm.c into irq.c

[Sean Christopherson]

Drop irq_comm.c, a.k.a. common IRQ APIs, as there has been no non-x86 user
since commit 003f7de62589 ("KVM: ia64: remove") (at the time, irq_comm.c
lived in virt/kvm, not arch/x86/kvm).

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/Makefile   |   6 +-
 arch/x86/kvm/irq.c      | 304 ++++++++++++++++++++++++++++++++++++-
 arch/x86/kvm/irq_comm.c | 325 ----------------------------------------
 3 files changed, 305 insertions(+), 330 deletions(-)
 delete mode 100644 arch/x86/kvm/irq_comm.c

diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 92c737257789..c4b8950c7abe 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -5,10 +5,8 @@ ccflags-$(CONFIG_KVM_WERROR) += -Werror
 
 include $(srctree)/virt/kvm/Makefile.kvm
 
-kvm-y			+= x86.o emulate.o irq.o lapic.o \
-			   irq_comm.o cpuid.o pmu.o mtrr.o \
-			   debugfs.o mmu/mmu.o mmu/page_track.o \
-			   mmu/spte.o
+kvm-y			+= x86.o emulate.o irq.o lapic.o cpuid.o pmu.o mtrr.o \
+			   debugfs.o mmu/mmu.o mmu/page_track.o mmu/spte.o
 
 kvm-$(CONFIG_X86_64) += mmu/tdp_iter.o mmu/tdp_mmu.o
 kvm-$(CONFIG_KVM_IOAPIC) += i8259.o i8254.o ioapic.o
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index 4c219e9f52b0..a0b1499baf6e 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -12,9 +12,10 @@
 #include <linux/export.h>
 #include <linux/kvm_host.h>
 
+#include "hyperv.h"
 #include "ioapic.h"
 #include "irq.h"
-#include "i8254.h"
+#include "trace.h"
 #include "x86.h"
 #include "xen.h"
 
@@ -193,6 +194,307 @@ bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
 	return irqchip_in_kernel(kvm);
 }
 
+int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
+			     struct kvm_lapic_irq *irq, struct dest_map *dest_map)
+{
+	int r = -1;
+	struct kvm_vcpu *vcpu, *lowest = NULL;
+	unsigned long i, dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)];
+	unsigned int dest_vcpus = 0;
+
+	if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
+		return r;
+
+	if (irq->dest_mode == APIC_DEST_PHYSICAL &&
+	    irq->dest_id == 0xff && kvm_lowest_prio_delivery(irq)) {
+		pr_info("apic: phys broadcast and lowest prio\n");
+		irq->delivery_mode = APIC_DM_FIXED;
+	}
+
+	memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap));
+
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		if (!kvm_apic_present(vcpu))
+			continue;
+
+		if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
+					irq->dest_id, irq->dest_mode))
+			continue;
+
+		if (!kvm_lowest_prio_delivery(irq)) {
+			if (r < 0)
+				r = 0;
+			r += kvm_apic_set_irq(vcpu, irq, dest_map);
+		} else if (kvm_apic_sw_enabled(vcpu->arch.apic)) {
+			if (!kvm_vector_hashing_enabled()) {
+				if (!lowest)
+					lowest = vcpu;
+				else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
+					lowest = vcpu;
+			} else {
+				__set_bit(i, dest_vcpu_bitmap);
+				dest_vcpus++;
+			}
+		}
+	}
+
+	if (dest_vcpus != 0) {
+		int idx = kvm_vector_to_index(irq->vector, dest_vcpus,
+					dest_vcpu_bitmap, KVM_MAX_VCPUS);
+
+		lowest = kvm_get_vcpu(kvm, idx);
+	}
+
+	if (lowest)
+		r = kvm_apic_set_irq(lowest, irq, dest_map);
+
+	return r;
+}
+
+void kvm_set_msi_irq(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e,
+		     struct kvm_lapic_irq *irq)
+{
+	struct msi_msg msg = { .address_lo = e->msi.address_lo,
+			       .address_hi = e->msi.address_hi,
+			       .data = e->msi.data };
+
+	trace_kvm_msi_set_irq(msg.address_lo | (kvm->arch.x2apic_format ?
+			      (u64)msg.address_hi << 32 : 0), msg.data);
+
+	irq->dest_id = x86_msi_msg_get_destid(&msg, kvm->arch.x2apic_format);
+	irq->vector = msg.arch_data.vector;
+	irq->dest_mode = kvm_lapic_irq_dest_mode(msg.arch_addr_lo.dest_mode_logical);
+	irq->trig_mode = msg.arch_data.is_level;
+	irq->delivery_mode = msg.arch_data.delivery_mode << 8;
+	irq->msi_redir_hint = msg.arch_addr_lo.redirect_hint;
+	irq->level = 1;
+	irq->shorthand = APIC_DEST_NOSHORT;
+}
+EXPORT_SYMBOL_GPL(kvm_set_msi_irq);
+
+static inline bool kvm_msi_route_invalid(struct kvm *kvm,
+		struct kvm_kernel_irq_routing_entry *e)
+{
+	return kvm->arch.x2apic_format && (e->msi.address_hi & 0xff);
+}
+
+int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
+		struct kvm *kvm, int irq_source_id, int level, bool line_status)
+{
+	struct kvm_lapic_irq irq;
+
+	if (kvm_msi_route_invalid(kvm, e))
+		return -EINVAL;
+
+	if (!level)
+		return -1;
+
+	kvm_set_msi_irq(kvm, e, &irq);
+
+	return kvm_irq_delivery_to_apic(kvm, NULL, &irq, NULL);
+}
+
+int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
+			      struct kvm *kvm, int irq_source_id, int level,
+			      bool line_status)
+{
+	struct kvm_lapic_irq irq;
+	int r;
+
+	switch (e->type) {
+#ifdef CONFIG_KVM_HYPERV
+	case KVM_IRQ_ROUTING_HV_SINT:
+		return kvm_hv_synic_set_irq(e, kvm, irq_source_id, level,
+					    line_status);
+#endif
+
+	case KVM_IRQ_ROUTING_MSI:
+		if (kvm_msi_route_invalid(kvm, e))
+			return -EINVAL;
+
+		kvm_set_msi_irq(kvm, e, &irq);
+
+		if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r, NULL))
+			return r;
+		break;
+
+#ifdef CONFIG_KVM_XEN
+	case KVM_IRQ_ROUTING_XEN_EVTCHN:
+		if (!level)
+			return -1;
+
+		return kvm_xen_set_evtchn_fast(&e->xen_evtchn, kvm);
+#endif
+	default:
+		break;
+	}
+
+	return -EWOULDBLOCK;
+}
+
+bool kvm_arch_can_set_irq_routing(struct kvm *kvm)
+{
+	return irqchip_in_kernel(kvm);
+}
+
+int kvm_set_routing_entry(struct kvm *kvm,
+			  struct kvm_kernel_irq_routing_entry *e,
+			  const struct kvm_irq_routing_entry *ue)
+{
+	/* We can't check irqchip_in_kernel() here as some callers are
+	 * currently initializing the irqchip. Other callers should therefore
+	 * check kvm_arch_can_set_irq_routing() before calling this function.
+	 */
+	switch (ue->type) {
+#ifdef CONFIG_KVM_IOAPIC
+	case KVM_IRQ_ROUTING_IRQCHIP:
+		if (irqchip_split(kvm))
+			return -EINVAL;
+		e->irqchip.pin = ue->u.irqchip.pin;
+		switch (ue->u.irqchip.irqchip) {
+		case KVM_IRQCHIP_PIC_SLAVE:
+			e->irqchip.pin += PIC_NUM_PINS / 2;
+			fallthrough;
+		case KVM_IRQCHIP_PIC_MASTER:
+			if (ue->u.irqchip.pin >= PIC_NUM_PINS / 2)
+				return -EINVAL;
+			e->set = kvm_pic_set_irq;
+			break;
+		case KVM_IRQCHIP_IOAPIC:
+			if (ue->u.irqchip.pin >= KVM_IOAPIC_NUM_PINS)
+				return -EINVAL;
+			e->set = kvm_ioapic_set_irq;
+			break;
+		default:
+			return -EINVAL;
+		}
+		e->irqchip.irqchip = ue->u.irqchip.irqchip;
+		break;
+#endif
+	case KVM_IRQ_ROUTING_MSI:
+		e->set = kvm_set_msi;
+		e->msi.address_lo = ue->u.msi.address_lo;
+		e->msi.address_hi = ue->u.msi.address_hi;
+		e->msi.data = ue->u.msi.data;
+
+		if (kvm_msi_route_invalid(kvm, e))
+			return -EINVAL;
+		break;
+#ifdef CONFIG_KVM_HYPERV
+	case KVM_IRQ_ROUTING_HV_SINT:
+		e->set = kvm_hv_synic_set_irq;
+		e->hv_sint.vcpu = ue->u.hv_sint.vcpu;
+		e->hv_sint.sint = ue->u.hv_sint.sint;
+		break;
+#endif
+#ifdef CONFIG_KVM_XEN
+	case KVM_IRQ_ROUTING_XEN_EVTCHN:
+		return kvm_xen_setup_evtchn(kvm, e, ue);
+#endif
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq,
+			     struct kvm_vcpu **dest_vcpu)
+{
+	int r = 0;
+	unsigned long i;
+	struct kvm_vcpu *vcpu;
+
+	if (kvm_intr_is_single_vcpu_fast(kvm, irq, dest_vcpu))
+		return true;
+
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		if (!kvm_apic_present(vcpu))
+			continue;
+
+		if (!kvm_apic_match_dest(vcpu, NULL, irq->shorthand,
+					irq->dest_id, irq->dest_mode))
+			continue;
+
+		if (++r == 2)
+			return false;
+
+		*dest_vcpu = vcpu;
+	}
+
+	return r == 1;
+}
+EXPORT_SYMBOL_GPL(kvm_intr_is_single_vcpu);
+
+void kvm_scan_ioapic_irq(struct kvm_vcpu *vcpu, u32 dest_id, u16 dest_mode,
+			 u8 vector, unsigned long *ioapic_handled_vectors)
+{
+	/*
+	 * Intercept EOI if the vCPU is the target of the new IRQ routing, or
+	 * the vCPU has a pending IRQ from the old routing, i.e. if the vCPU
+	 * may receive a level-triggered IRQ in the future, or already received
+	 * level-triggered IRQ.  The EOI needs to be intercepted and forwarded
+	 * to I/O APIC emulation so that the IRQ can be de-asserted.
+	 */
+	if (kvm_apic_match_dest(vcpu, NULL, APIC_DEST_NOSHORT, dest_id, dest_mode)) {
+		__set_bit(vector, ioapic_handled_vectors);
+	} else if (kvm_apic_pending_eoi(vcpu, vector)) {
+		__set_bit(vector, ioapic_handled_vectors);
+
+		/*
+		 * Track the highest pending EOI for which the vCPU is NOT the
+		 * target in the new routing.  Only the EOI for the IRQ that is
+		 * in-flight (for the old routing) needs to be intercepted, any
+		 * future IRQs that arrive on this vCPU will be coincidental to
+		 * the level-triggered routing and don't need to be intercepted.
+		 */
+		if ((int)vector > vcpu->arch.highest_stale_pending_ioapic_eoi)
+			vcpu->arch.highest_stale_pending_ioapic_eoi = vector;
+	}
+}
+
+void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu,
+			    ulong *ioapic_handled_vectors)
+{
+	struct kvm *kvm = vcpu->kvm;
+	struct kvm_kernel_irq_routing_entry *entry;
+	struct kvm_irq_routing_table *table;
+	u32 i, nr_ioapic_pins;
+	int idx;
+
+	idx = srcu_read_lock(&kvm->irq_srcu);
+	table = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
+	nr_ioapic_pins = min_t(u32, table->nr_rt_entries,
+			       kvm->arch.nr_reserved_ioapic_pins);
+	for (i = 0; i < nr_ioapic_pins; ++i) {
+		hlist_for_each_entry(entry, &table->map[i], link) {
+			struct kvm_lapic_irq irq;
+
+			if (entry->type != KVM_IRQ_ROUTING_MSI)
+				continue;
+
+			kvm_set_msi_irq(vcpu->kvm, entry, &irq);
+
+			if (!irq.trig_mode)
+				continue;
+
+			kvm_scan_ioapic_irq(vcpu, irq.dest_id, irq.dest_mode,
+					    irq.vector, ioapic_handled_vectors);
+		}
+	}
+	srcu_read_unlock(&kvm->irq_srcu, idx);
+}
+
+void kvm_arch_irq_routing_update(struct kvm *kvm)
+{
+#ifdef CONFIG_KVM_HYPERV
+	kvm_hv_irq_routing_update(kvm);
+#endif
+
+	if (irqchip_split(kvm))
+		kvm_make_scan_ioapic_request(kvm);
+}
+
 #ifdef CONFIG_KVM_IOAPIC
 #define IOAPIC_ROUTING_ENTRY(irq) \
 	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
deleted file mode 100644
index 76d1c85a1011..000000000000
--- a/arch/x86/kvm/irq_comm.c
+++ /dev/null
@@ -1,325 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * irq_comm.c: Common API for in kernel interrupt controller
- * Copyright (c) 2007, Intel Corporation.
- *
- * Authors:
- *   Yaozu (Eddie) Dong <Eddie.dong@intel.com>
- *
- * Copyright 2010 Red Hat, Inc. and/or its affiliates.
- */
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/kvm_host.h>
-#include <linux/slab.h>
-#include <linux/export.h>
-#include <linux/rculist.h>
-
-#include "hyperv.h"
-#include "ioapic.h"
-#include "irq.h"
-#include "lapic.h"
-#include "trace.h"
-#include "x86.h"
-#include "xen.h"
-
-int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
-		struct kvm_lapic_irq *irq, struct dest_map *dest_map)
-{
-	int r = -1;
-	struct kvm_vcpu *vcpu, *lowest = NULL;
-	unsigned long i, dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)];
-	unsigned int dest_vcpus = 0;
-
-	if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
-		return r;
-
-	if (irq->dest_mode == APIC_DEST_PHYSICAL &&
-	    irq->dest_id == 0xff && kvm_lowest_prio_delivery(irq)) {
-		pr_info("apic: phys broadcast and lowest prio\n");
-		irq->delivery_mode = APIC_DM_FIXED;
-	}
-
-	memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap));
-
-	kvm_for_each_vcpu(i, vcpu, kvm) {
-		if (!kvm_apic_present(vcpu))
-			continue;
-
-		if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
-					irq->dest_id, irq->dest_mode))
-			continue;
-
-		if (!kvm_lowest_prio_delivery(irq)) {
-			if (r < 0)
-				r = 0;
-			r += kvm_apic_set_irq(vcpu, irq, dest_map);
-		} else if (kvm_apic_sw_enabled(vcpu->arch.apic)) {
-			if (!kvm_vector_hashing_enabled()) {
-				if (!lowest)
-					lowest = vcpu;
-				else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
-					lowest = vcpu;
-			} else {
-				__set_bit(i, dest_vcpu_bitmap);
-				dest_vcpus++;
-			}
-		}
-	}
-
-	if (dest_vcpus != 0) {
-		int idx = kvm_vector_to_index(irq->vector, dest_vcpus,
-					dest_vcpu_bitmap, KVM_MAX_VCPUS);
-
-		lowest = kvm_get_vcpu(kvm, idx);
-	}
-
-	if (lowest)
-		r = kvm_apic_set_irq(lowest, irq, dest_map);
-
-	return r;
-}
-
-void kvm_set_msi_irq(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e,
-		     struct kvm_lapic_irq *irq)
-{
-	struct msi_msg msg = { .address_lo = e->msi.address_lo,
-			       .address_hi = e->msi.address_hi,
-			       .data = e->msi.data };
-
-	trace_kvm_msi_set_irq(msg.address_lo | (kvm->arch.x2apic_format ?
-			      (u64)msg.address_hi << 32 : 0), msg.data);
-
-	irq->dest_id = x86_msi_msg_get_destid(&msg, kvm->arch.x2apic_format);
-	irq->vector = msg.arch_data.vector;
-	irq->dest_mode = kvm_lapic_irq_dest_mode(msg.arch_addr_lo.dest_mode_logical);
-	irq->trig_mode = msg.arch_data.is_level;
-	irq->delivery_mode = msg.arch_data.delivery_mode << 8;
-	irq->msi_redir_hint = msg.arch_addr_lo.redirect_hint;
-	irq->level = 1;
-	irq->shorthand = APIC_DEST_NOSHORT;
-}
-EXPORT_SYMBOL_GPL(kvm_set_msi_irq);
-
-static inline bool kvm_msi_route_invalid(struct kvm *kvm,
-		struct kvm_kernel_irq_routing_entry *e)
-{
-	return kvm->arch.x2apic_format && (e->msi.address_hi & 0xff);
-}
-
-int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
-		struct kvm *kvm, int irq_source_id, int level, bool line_status)
-{
-	struct kvm_lapic_irq irq;
-
-	if (kvm_msi_route_invalid(kvm, e))
-		return -EINVAL;
-
-	if (!level)
-		return -1;
-
-	kvm_set_msi_irq(kvm, e, &irq);
-
-	return kvm_irq_delivery_to_apic(kvm, NULL, &irq, NULL);
-}
-
-int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
-			      struct kvm *kvm, int irq_source_id, int level,
-			      bool line_status)
-{
-	struct kvm_lapic_irq irq;
-	int r;
-
-	switch (e->type) {
-#ifdef CONFIG_KVM_HYPERV
-	case KVM_IRQ_ROUTING_HV_SINT:
-		return kvm_hv_synic_set_irq(e, kvm, irq_source_id, level,
-					    line_status);
-#endif
-
-	case KVM_IRQ_ROUTING_MSI:
-		if (kvm_msi_route_invalid(kvm, e))
-			return -EINVAL;
-
-		kvm_set_msi_irq(kvm, e, &irq);
-
-		if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r, NULL))
-			return r;
-		break;
-
-#ifdef CONFIG_KVM_XEN
-	case KVM_IRQ_ROUTING_XEN_EVTCHN:
-		if (!level)
-			return -1;
-
-		return kvm_xen_set_evtchn_fast(&e->xen_evtchn, kvm);
-#endif
-	default:
-		break;
-	}
-
-	return -EWOULDBLOCK;
-}
-
-bool kvm_arch_can_set_irq_routing(struct kvm *kvm)
-{
-	return irqchip_in_kernel(kvm);
-}
-
-int kvm_set_routing_entry(struct kvm *kvm,
-			  struct kvm_kernel_irq_routing_entry *e,
-			  const struct kvm_irq_routing_entry *ue)
-{
-	/* We can't check irqchip_in_kernel() here as some callers are
-	 * currently initializing the irqchip. Other callers should therefore
-	 * check kvm_arch_can_set_irq_routing() before calling this function.
-	 */
-	switch (ue->type) {
-#ifdef CONFIG_KVM_IOAPIC
-	case KVM_IRQ_ROUTING_IRQCHIP:
-		if (irqchip_split(kvm))
-			return -EINVAL;
-		e->irqchip.pin = ue->u.irqchip.pin;
-		switch (ue->u.irqchip.irqchip) {
-		case KVM_IRQCHIP_PIC_SLAVE:
-			e->irqchip.pin += PIC_NUM_PINS / 2;
-			fallthrough;
-		case KVM_IRQCHIP_PIC_MASTER:
-			if (ue->u.irqchip.pin >= PIC_NUM_PINS / 2)
-				return -EINVAL;
-			e->set = kvm_pic_set_irq;
-			break;
-		case KVM_IRQCHIP_IOAPIC:
-			if (ue->u.irqchip.pin >= KVM_IOAPIC_NUM_PINS)
-				return -EINVAL;
-			e->set = kvm_ioapic_set_irq;
-			break;
-		default:
-			return -EINVAL;
-		}
-		e->irqchip.irqchip = ue->u.irqchip.irqchip;
-		break;
-#endif
-	case KVM_IRQ_ROUTING_MSI:
-		e->set = kvm_set_msi;
-		e->msi.address_lo = ue->u.msi.address_lo;
-		e->msi.address_hi = ue->u.msi.address_hi;
-		e->msi.data = ue->u.msi.data;
-
-		if (kvm_msi_route_invalid(kvm, e))
-			return -EINVAL;
-		break;
-#ifdef CONFIG_KVM_HYPERV
-	case KVM_IRQ_ROUTING_HV_SINT:
-		e->set = kvm_hv_synic_set_irq;
-		e->hv_sint.vcpu = ue->u.hv_sint.vcpu;
-		e->hv_sint.sint = ue->u.hv_sint.sint;
-		break;
-#endif
-#ifdef CONFIG_KVM_XEN
-	case KVM_IRQ_ROUTING_XEN_EVTCHN:
-		return kvm_xen_setup_evtchn(kvm, e, ue);
-#endif
-	default:
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq,
-			     struct kvm_vcpu **dest_vcpu)
-{
-	int r = 0;
-	unsigned long i;
-	struct kvm_vcpu *vcpu;
-
-	if (kvm_intr_is_single_vcpu_fast(kvm, irq, dest_vcpu))
-		return true;
-
-	kvm_for_each_vcpu(i, vcpu, kvm) {
-		if (!kvm_apic_present(vcpu))
-			continue;
-
-		if (!kvm_apic_match_dest(vcpu, NULL, irq->shorthand,
-					irq->dest_id, irq->dest_mode))
-			continue;
-
-		if (++r == 2)
-			return false;
-
-		*dest_vcpu = vcpu;
-	}
-
-	return r == 1;
-}
-EXPORT_SYMBOL_GPL(kvm_intr_is_single_vcpu);
-
-void kvm_scan_ioapic_irq(struct kvm_vcpu *vcpu, u32 dest_id, u16 dest_mode,
-			 u8 vector, unsigned long *ioapic_handled_vectors)
-{
-	/*
-	 * Intercept EOI if the vCPU is the target of the new IRQ routing, or
-	 * the vCPU has a pending IRQ from the old routing, i.e. if the vCPU
-	 * may receive a level-triggered IRQ in the future, or already received
-	 * level-triggered IRQ.  The EOI needs to be intercepted and forwarded
-	 * to I/O APIC emulation so that the IRQ can be de-asserted.
-	 */
-	if (kvm_apic_match_dest(vcpu, NULL, APIC_DEST_NOSHORT, dest_id, dest_mode)) {
-		__set_bit(vector, ioapic_handled_vectors);
-	} else if (kvm_apic_pending_eoi(vcpu, vector)) {
-		__set_bit(vector, ioapic_handled_vectors);
-
-		/*
-		 * Track the highest pending EOI for which the vCPU is NOT the
-		 * target in the new routing.  Only the EOI for the IRQ that is
-		 * in-flight (for the old routing) needs to be intercepted, any
-		 * future IRQs that arrive on this vCPU will be coincidental to
-		 * the level-triggered routing and don't need to be intercepted.
-		 */
-		if ((int)vector > vcpu->arch.highest_stale_pending_ioapic_eoi)
-			vcpu->arch.highest_stale_pending_ioapic_eoi = vector;
-	}
-}
-
-void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu,
-			    ulong *ioapic_handled_vectors)
-{
-	struct kvm *kvm = vcpu->kvm;
-	struct kvm_kernel_irq_routing_entry *entry;
-	struct kvm_irq_routing_table *table;
-	u32 i, nr_ioapic_pins;
-	int idx;
-
-	idx = srcu_read_lock(&kvm->irq_srcu);
-	table = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
-	nr_ioapic_pins = min_t(u32, table->nr_rt_entries,
-			       kvm->arch.nr_reserved_ioapic_pins);
-	for (i = 0; i < nr_ioapic_pins; ++i) {
-		hlist_for_each_entry(entry, &table->map[i], link) {
-			struct kvm_lapic_irq irq;
-
-			if (entry->type != KVM_IRQ_ROUTING_MSI)
-				continue;
-
-			kvm_set_msi_irq(vcpu->kvm, entry, &irq);
-
-			if (!irq.trig_mode)
-				continue;
-
-			kvm_scan_ioapic_irq(vcpu, irq.dest_id, irq.dest_mode,
-					    irq.vector, ioapic_handled_vectors);
-		}
-	}
-	srcu_read_unlock(&kvm->irq_srcu, idx);
-}
-
-void kvm_arch_irq_routing_update(struct kvm *kvm)
-{
-#ifdef CONFIG_KVM_HYPERV
-	kvm_hv_irq_routing_update(kvm);
-#endif
-
-	if (irqchip_split(kvm))
-		kvm_make_scan_ioapic_request(kvm);
-}
-- 
2.50.0.rc1.591.g9c95f17f64-goog

Re: [PATCH v2 00/18] KVM: x86: Add I/O APIC kconfig, delete irq_comm.c

[Sean Christopherson]

On Wed, 11 Jun 2025 14:35:39 -0700, Sean Christopherson wrote:
> Add CONFIG_KVM_IOAPIC to allow disabling support for KVM's I/O APIC (and PIC
> and PIT) emulation, and delete irq_comm.c by moving its contents to other
> files.
> 
> Vitaly and Kai, I didn't apply your review/ack to the Hyper-V patch, as I ended
> up keeping the helper as kvm_hv_synic_set_irq() to fix the tracepoint
> inconsistency and the bad changelog.
> 
> [...]

Applied to kvm-x86 irqs, thanks!

[01/18] KVM: x86: Trigger I/O APIC route rescan in kvm_arch_irq_routing_update()
        https://github.com/kvm-x86/linux/commit/e295d2e7fbe6
[02/18] KVM: x86: Drop superfluous kvm_set_pic_irq() => kvm_pic_set_irq() wrapper
        https://github.com/kvm-x86/linux/commit/8a33b1f246ce
[03/18] KVM: x86: Drop superfluous kvm_set_ioapic_irq() => kvm_ioapic_set_irq() wrapper
        https://github.com/kvm-x86/linux/commit/05dc9eab3f00
[04/18] KVM: x86: Drop superfluous kvm_hv_set_sint() => kvm_hv_synic_set_irq() wrapper
        https://github.com/kvm-x86/linux/commit/20218e69e85b
[05/18] KVM: x86: Move PIT ioctl helpers to i8254.c
        https://github.com/kvm-x86/linux/commit/00b5ebf8db7c
[06/18] KVM: x86: Move KVM_{GET,SET}_IRQCHIP ioctl helpers to irq.c
        https://github.com/kvm-x86/linux/commit/b771b1616ff8
[07/18] KVM: x86: Rename irqchip_kernel() to irqchip_full()
        https://github.com/kvm-x86/linux/commit/c5a701955e2d
[08/18] KVM: x86: Move kvm_setup_default_irq_routing() into irq.c
        https://github.com/kvm-x86/linux/commit/df35135680fa
[09/18] KVM: x86: Move kvm_{request,free}_irq_source_id() to i8254.c (PIT)
        https://github.com/kvm-x86/linux/commit/77a74b8ff41a
[10/18] KVM: x86: Hardcode the PIT IRQ source ID to '2'
        https://github.com/kvm-x86/linux/commit/61423c413a74
[11/18] KVM: x86: Don't clear PIT's IRQ line status when destroying PIT
        https://github.com/kvm-x86/linux/commit/2c31aa747d78
[12/18] KVM: x86: Explicitly check for in-kernel PIC when getting ExtINT
        https://github.com/kvm-x86/linux/commit/cd9140ad8312
[13/18] KVM: Move x86-only tracepoints to x86's trace.h
        https://github.com/kvm-x86/linux/commit/2c938850d9d1
[14/18] KVM: x86: Add CONFIG_KVM_IOAPIC to allow disabling in-kernel I/O APIC
        https://github.com/kvm-x86/linux/commit/628a27731e3f
[15/18] KVM: Squash two CONFIG_HAVE_KVM_IRQCHIP #ifdefs into one
        https://github.com/kvm-x86/linux/commit/141db6cd79e2
[16/18] KVM: selftests: Fall back to split IRQ chip if full in-kernel chip is unsupported
        https://github.com/kvm-x86/linux/commit/8fd2a6d43a10
[17/18] KVM: x86: Move IRQ mask notifier infrastructure to I/O APIC emulation
        https://github.com/kvm-x86/linux/commit/37b1761fe895
[18/18] KVM: x86: Fold irq_comm.c into irq.c
        https://github.com/kvm-x86/linux/commit/e76c274513f2

--
https://github.com/kvm-x86/kvm-unit-tests/tree/next