diff --git a/arch/x86/kernel/apic/apic_common.c b/arch/x86/kernel/apic/apic_common.c
index ddc6a4301588321d0378d00406ab371b2ac54410..a360801779ae92164240f9cec48cbc1660b5c11f 100644
--- a/arch/x86/kernel/apic/apic_common.c
+++ b/arch/x86/kernel/apic/apic_common.c
@@ -11,64 +11,16 @@ u32 apic_default_calc_apicid(unsigned int cpu)
 	return per_cpu(x86_cpu_to_apicid, cpu);
 }
 
-int default_cpu_mask_to_apicid(const struct cpumask *msk, struct irq_data *irqd,
-			       unsigned int *apicid)
-{
-	unsigned int cpu = cpumask_first(msk);
-
-	if (cpu >= nr_cpu_ids)
-		return -EINVAL;
-	*apicid = per_cpu(x86_cpu_to_apicid, cpu);
-	irq_data_update_effective_affinity(irqd, cpumask_of(cpu));
-	return 0;
-}
-
 u32 apic_flat_calc_apicid(unsigned int cpu)
 {
 	return 1U << cpu;
 }
 
-int flat_cpu_mask_to_apicid(const struct cpumask *mask, struct irq_data *irqd,
-			    unsigned int *apicid)
-
-{
-	struct cpumask *effmsk = irq_data_get_effective_affinity_mask(irqd);
-	unsigned long cpu_mask = cpumask_bits(mask)[0] & APIC_ALL_CPUS;
-
-	if (!cpu_mask)
-		return -EINVAL;
-	*apicid = (unsigned int)cpu_mask;
-	cpumask_bits(effmsk)[0] = cpu_mask;
-	return 0;
-}
-
 bool default_check_apicid_used(physid_mask_t *map, int apicid)
 {
 	return physid_isset(apicid, *map);
 }
 
-void flat_vector_allocation_domain(int cpu, struct cpumask *retmask,
-				   const struct cpumask *mask)
-{
-	/*
-	 * Careful. Some cpus do not strictly honor the set of cpus
-	 * specified in the interrupt destination when using lowest
-	 * priority interrupt delivery mode.
-	 *
-	 * In particular there was a hyperthreading cpu observed to
-	 * deliver interrupts to the wrong hyperthread when only one
-	 * hyperthread was specified in the interrupt desitination.
-	 */
-	cpumask_clear(retmask);
-	cpumask_bits(retmask)[0] = APIC_ALL_CPUS;
-}
-
-void default_vector_allocation_domain(int cpu, struct cpumask *retmask,
-				      const struct cpumask *mask)
-{
-	cpumask_copy(retmask, cpumask_of(cpu));
-}
-
 void default_ioapic_phys_id_map(physid_mask_t *phys_map, physid_mask_t *retmap)
 {
 	*retmap = *phys_map;
diff --git a/arch/x86/kernel/apic/apic_flat_64.c b/arch/x86/kernel/apic/apic_flat_64.c
index 697704443fdaa01c9e85c3f9933bba46295acdbb..aa85690e9b6416b797db8129c8f1cbd7606bf687 100644
--- a/arch/x86/kernel/apic/apic_flat_64.c
+++ b/arch/x86/kernel/apic/apic_flat_64.c
@@ -158,7 +158,6 @@ static struct apic apic_flat __ro_after_init = {
 	.dest_logical			= APIC_DEST_LOGICAL,
 	.check_apicid_used		= NULL,
 
-	.vector_allocation_domain	= flat_vector_allocation_domain,
 	.init_apic_ldr			= flat_init_apic_ldr,
 
 	.ioapic_phys_id_map		= NULL,
@@ -171,7 +170,6 @@ static struct apic apic_flat __ro_after_init = {
 	.get_apic_id			= flat_get_apic_id,
 	.set_apic_id			= set_apic_id,
 
-	.cpu_mask_to_apicid		= flat_cpu_mask_to_apicid,
 	.calc_dest_apicid		= apic_flat_calc_apicid,
 
 	.send_IPI			= default_send_IPI_single,
@@ -253,7 +251,6 @@ static struct apic apic_physflat __ro_after_init = {
 	.dest_logical			= 0,
 	.check_apicid_used		= NULL,
 
-	.vector_allocation_domain	= default_vector_allocation_domain,
 	/* not needed, but shouldn't hurt: */
 	.init_apic_ldr			= flat_init_apic_ldr,
 
@@ -267,7 +264,6 @@ static struct apic apic_physflat __ro_after_init = {
 	.get_apic_id			= flat_get_apic_id,
 	.set_apic_id			= set_apic_id,
 
-	.cpu_mask_to_apicid		= default_cpu_mask_to_apicid,
 	.calc_dest_apicid		= apic_default_calc_apicid,
 
 	.send_IPI			= default_send_IPI_single_phys,
diff --git a/arch/x86/kernel/apic/apic_noop.c b/arch/x86/kernel/apic/apic_noop.c
index d8c24e6f1a1168e35fffdca220120cc53e660982..0285f28d531acc899a1fdd365eba77bc66e91c46 100644
--- a/arch/x86/kernel/apic/apic_noop.c
+++ b/arch/x86/kernel/apic/apic_noop.c
@@ -83,14 +83,6 @@ static int noop_apic_id_registered(void)
 	return physid_isset(0, phys_cpu_present_map);
 }
 
-static void noop_vector_allocation_domain(int cpu, struct cpumask *retmask,
-					  const struct cpumask *mask)
-{
-	if (cpu != 0)
-		pr_warning("APIC: Vector allocated for non-BSP cpu\n");
-	cpumask_copy(retmask, cpumask_of(cpu));
-}
-
 static u32 noop_apic_read(u32 reg)
 {
 	WARN_ON_ONCE(boot_cpu_has(X86_FEATURE_APIC) && !disable_apic);
@@ -125,7 +117,6 @@ struct apic apic_noop __ro_after_init = {
 	.dest_logical			= APIC_DEST_LOGICAL,
 	.check_apicid_used		= default_check_apicid_used,
 
-	.vector_allocation_domain	= noop_vector_allocation_domain,
 	.init_apic_ldr			= noop_init_apic_ldr,
 
 	.ioapic_phys_id_map		= default_ioapic_phys_id_map,
@@ -141,7 +132,6 @@ struct apic apic_noop __ro_after_init = {
 	.get_apic_id			= noop_get_apic_id,
 	.set_apic_id			= NULL,
 
-	.cpu_mask_to_apicid		= flat_cpu_mask_to_apicid,
 	.calc_dest_apicid		= apic_flat_calc_apicid,
 
 	.send_IPI			= noop_send_IPI,
diff --git a/arch/x86/kernel/apic/apic_numachip.c b/arch/x86/kernel/apic/apic_numachip.c
index 4ec293b30eb84d7462791793009074b490350dbd..134e04506ab41419f41ddf1ee6edf767d95e0088 100644
--- a/arch/x86/kernel/apic/apic_numachip.c
+++ b/arch/x86/kernel/apic/apic_numachip.c
@@ -253,7 +253,6 @@ static const struct apic apic_numachip1 __refconst = {
 	.dest_logical			= 0,
 	.check_apicid_used		= NULL,
 
-	.vector_allocation_domain	= default_vector_allocation_domain,
 	.init_apic_ldr			= flat_init_apic_ldr,
 
 	.ioapic_phys_id_map		= NULL,
@@ -266,7 +265,6 @@ static const struct apic apic_numachip1 __refconst = {
 	.get_apic_id			= numachip1_get_apic_id,
 	.set_apic_id			= numachip1_set_apic_id,
 
-	.cpu_mask_to_apicid		= default_cpu_mask_to_apicid,
 	.calc_dest_apicid		= apic_default_calc_apicid,
 
 	.send_IPI			= numachip_send_IPI_one,
@@ -304,7 +302,6 @@ static const struct apic apic_numachip2 __refconst = {
 	.dest_logical			= 0,
 	.check_apicid_used		= NULL,
 
-	.vector_allocation_domain	= default_vector_allocation_domain,
 	.init_apic_ldr			= flat_init_apic_ldr,
 
 	.ioapic_phys_id_map		= NULL,
@@ -317,7 +314,6 @@ static const struct apic apic_numachip2 __refconst = {
 	.get_apic_id			= numachip2_get_apic_id,
 	.set_apic_id			= numachip2_set_apic_id,
 
-	.cpu_mask_to_apicid		= default_cpu_mask_to_apicid,
 	.calc_dest_apicid		= apic_default_calc_apicid,
 
 	.send_IPI			= numachip_send_IPI_one,
diff --git a/arch/x86/kernel/apic/bigsmp_32.c b/arch/x86/kernel/apic/bigsmp_32.c
index de2e8597f2df28ce62e80c011e0c7783240de2c0..7b754c513fa5b409377e4e6f0eb64b469d16e121 100644
--- a/arch/x86/kernel/apic/bigsmp_32.c
+++ b/arch/x86/kernel/apic/bigsmp_32.c
@@ -158,7 +158,6 @@ static struct apic apic_bigsmp __ro_after_init = {
 	.dest_logical			= 0,
 	.check_apicid_used		= bigsmp_check_apicid_used,
 
-	.vector_allocation_domain	= default_vector_allocation_domain,
 	.init_apic_ldr			= bigsmp_init_apic_ldr,
 
 	.ioapic_phys_id_map		= bigsmp_ioapic_phys_id_map,
@@ -171,7 +170,6 @@ static struct apic apic_bigsmp __ro_after_init = {
 	.get_apic_id			= bigsmp_get_apic_id,
 	.set_apic_id			= NULL,
 
-	.cpu_mask_to_apicid		= default_cpu_mask_to_apicid,
 	.calc_dest_apicid		= apic_default_calc_apicid,
 
 	.send_IPI			= default_send_IPI_single_phys,
diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c
index 6a9020a3c2434e496b28610768e6e41584fae274..fa22017de806504b79593ead951bffe4e5d5421b 100644
--- a/arch/x86/kernel/apic/probe_32.c
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -113,7 +113,6 @@ static struct apic apic_default __ro_after_init = {
 	.dest_logical			= APIC_DEST_LOGICAL,
 	.check_apicid_used		= default_check_apicid_used,
 
-	.vector_allocation_domain	= flat_vector_allocation_domain,
 	.init_apic_ldr			= default_init_apic_ldr,
 
 	.ioapic_phys_id_map		= default_ioapic_phys_id_map,
@@ -126,7 +125,6 @@ static struct apic apic_default __ro_after_init = {
 	.get_apic_id			= default_get_apic_id,
 	.set_apic_id			= NULL,
 
-	.cpu_mask_to_apicid		= flat_cpu_mask_to_apicid,
 	.calc_dest_apicid		= apic_flat_calc_apicid,
 
 	.send_IPI			= default_send_IPI_single,
diff --git a/arch/x86/kernel/apic/x2apic_cluster.c b/arch/x86/kernel/apic/x2apic_cluster.c
index 17bf63f580d73fd1fa81fb2dc0bf8096050ae5ba..3da94277140fa3bc60b7b3106cb0e95fdcb7a24a 100644
--- a/arch/x86/kernel/apic/x2apic_cluster.c
+++ b/arch/x86/kernel/apic/x2apic_cluster.c
@@ -91,29 +91,6 @@ static void x2apic_send_IPI_all(int vector)
 	__x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLINC);
 }
 
-static int
-x2apic_cpu_mask_to_apicid(const struct cpumask *mask, struct irq_data *irqdata,
-			  unsigned int *apicid)
-{
-	struct cpumask *effmsk = irq_data_get_effective_affinity_mask(irqdata);
-	struct cluster_mask *cmsk;
-	unsigned int cpu;
-	u32 dest = 0;
-
-	cpu = cpumask_first(mask);
-	if (cpu >= nr_cpu_ids)
-		return -EINVAL;
-
-	cmsk = per_cpu(cluster_masks, cpu);
-	cpumask_clear(effmsk);
-	for_each_cpu_and(cpu, &cmsk->mask, mask) {
-		dest |= per_cpu(x86_cpu_to_logical_apicid, cpu);
-		cpumask_set_cpu(cpu, effmsk);
-	}
-	*apicid = dest;
-	return 0;
-}
-
 static u32 x2apic_calc_apicid(unsigned int cpu)
 {
 	return per_cpu(x86_cpu_to_logical_apicid, cpu);
@@ -198,29 +175,6 @@ static int x2apic_cluster_probe(void)
 	return 1;
 }
 
-/*
- * Each x2apic cluster is an allocation domain.
- */
-static void cluster_vector_allocation_domain(int cpu, struct cpumask *retmask,
-					     const struct cpumask *mask)
-{
-	struct cluster_mask *cmsk = per_cpu(cluster_masks, cpu);
-
-	/*
-	 * To minimize vector pressure, default case of boot, device bringup
-	 * etc will use a single cpu for the interrupt destination.
-	 *
-	 * On explicit migration requests coming from irqbalance etc,
-	 * interrupts will be routed to the x2apic cluster (cluster-id
-	 * derived from the first cpu in the mask) members specified
-	 * in the mask.
-	 */
-	if (cpumask_equal(mask, cpu_online_mask))
-		cpumask_copy(retmask, cpumask_of(cpu));
-	else
-		cpumask_and(retmask, mask, &cmsk->mask);
-}
-
 static struct apic apic_x2apic_cluster __ro_after_init = {
 
 	.name				= "cluster x2apic",
@@ -236,7 +190,6 @@ static struct apic apic_x2apic_cluster __ro_after_init = {
 	.dest_logical			= APIC_DEST_LOGICAL,
 	.check_apicid_used		= NULL,
 
-	.vector_allocation_domain	= cluster_vector_allocation_domain,
 	.init_apic_ldr			= init_x2apic_ldr,
 
 	.ioapic_phys_id_map		= NULL,
@@ -249,7 +202,6 @@ static struct apic apic_x2apic_cluster __ro_after_init = {
 	.get_apic_id			= x2apic_get_apic_id,
 	.set_apic_id			= x2apic_set_apic_id,
 
-	.cpu_mask_to_apicid		= x2apic_cpu_mask_to_apicid,
 	.calc_dest_apicid		= x2apic_calc_apicid,
 
 	.send_IPI			= x2apic_send_IPI,
diff --git a/arch/x86/kernel/apic/x2apic_phys.c b/arch/x86/kernel/apic/x2apic_phys.c
index ebad7ddbfdfc16d5fe0fb3aa7181c1d4fe0151c2..17c2c5b0b7b9c7d087ce993e69573ca0b8dfd699 100644
--- a/arch/x86/kernel/apic/x2apic_phys.c
+++ b/arch/x86/kernel/apic/x2apic_phys.c
@@ -151,7 +151,6 @@ static struct apic apic_x2apic_phys __ro_after_init = {
 	.dest_logical			= 0,
 	.check_apicid_used		= NULL,
 
-	.vector_allocation_domain	= default_vector_allocation_domain,
 	.init_apic_ldr			= init_x2apic_ldr,
 
 	.ioapic_phys_id_map		= NULL,
@@ -164,7 +163,6 @@ static struct apic apic_x2apic_phys __ro_after_init = {
 	.get_apic_id			= x2apic_get_apic_id,
 	.set_apic_id			= x2apic_set_apic_id,
 
-	.cpu_mask_to_apicid		= default_cpu_mask_to_apicid,
 	.calc_dest_apicid		= apic_default_calc_apicid,
 
 	.send_IPI			= x2apic_send_IPI,
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 99c3c039646d769bef7d280ec4cba0ad347c3c98..5832df6d9c37fc6f71a8836531178b3362748b45 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -525,18 +525,6 @@ static void uv_init_apic_ldr(void)
 {
 }
 
-static int
-uv_cpu_mask_to_apicid(const struct cpumask *mask, struct irq_data *irqdata,
-		      unsigned int *apicid)
-{
-	int ret = default_cpu_mask_to_apicid(mask, irqdata, apicid);
-
-	if (!ret)
-		*apicid |= uv_apicid_hibits;
-
-	return ret;
-}
-
 static u32 apic_uv_calc_apicid(unsigned int cpu)
 {
 	return apic_default_calc_apicid(cpu) | uv_apicid_hibits;
@@ -593,7 +581,6 @@ static struct apic apic_x2apic_uv_x __ro_after_init = {
 	.dest_logical			= APIC_DEST_LOGICAL,
 	.check_apicid_used		= NULL,
 
-	.vector_allocation_domain	= default_vector_allocation_domain,
 	.init_apic_ldr			= uv_init_apic_ldr,
 
 	.ioapic_phys_id_map		= NULL,
@@ -606,7 +593,6 @@ static struct apic apic_x2apic_uv_x __ro_after_init = {
 	.get_apic_id			= x2apic_get_apic_id,
 	.set_apic_id			= set_apic_id,
 
-	.cpu_mask_to_apicid		= uv_cpu_mask_to_apicid,
 	.calc_dest_apicid		= apic_uv_calc_apicid,
 
 	.send_IPI			= uv_send_IPI_one,
diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c
index b034b1b14b9c66ab77b24d9757ce10de7f0f318e..44685fb2a192f7969ed6453fb56c16ff5a33ca40 100644
--- a/arch/x86/kernel/vsmp_64.c
+++ b/arch/x86/kernel/vsmp_64.c
@@ -26,9 +26,6 @@
 
 #define TOPOLOGY_REGISTER_OFFSET 0x10
 
-/* Flag below is initialized once during vSMP PCI initialization. */
-static int irq_routing_comply = 1;
-
 #if defined CONFIG_PCI && defined CONFIG_PARAVIRT
 /*
  * Interrupt control on vSMPowered systems:
@@ -105,9 +102,6 @@ static void __init set_vsmp_pv_ops(void)
 	if (cap & ctl & BIT(8)) {
 		ctl &= ~BIT(8);
 
-		/* Interrupt routing set to ignore */
-		irq_routing_comply = 0;
-
 #ifdef CONFIG_PROC_FS
 		/* Don't let users change irq affinity via procfs */
 		no_irq_affinity = 1;
@@ -211,23 +205,10 @@ static int apicid_phys_pkg_id(int initial_apic_id, int index_msb)
 	return hard_smp_processor_id() >> index_msb;
 }
 
-/*
- * In vSMP, all cpus should be capable of handling interrupts, regardless of
- * the APIC used.
- */
-static void fill_vector_allocation_domain(int cpu, struct cpumask *retmask,
-					  const struct cpumask *mask)
-{
-	cpumask_setall(retmask);
-}
-
 static void vsmp_apic_post_init(void)
 {
 	/* need to update phys_pkg_id */
 	apic->phys_pkg_id = apicid_phys_pkg_id;
-
-	if (!irq_routing_comply)
-		apic->vector_allocation_domain = fill_vector_allocation_domain;
 }
 
 void __init vsmp_init(void)
diff --git a/arch/x86/xen/apic.c b/arch/x86/xen/apic.c
index fb8522bed08c49f0aca6204cab7493c375db2ca3..4ba3fd7039b0220ee7564ba202d50235cd9ca3a1 100644
--- a/arch/x86/xen/apic.c
+++ b/arch/x86/xen/apic.c
@@ -164,7 +164,6 @@ static struct apic xen_pv_apic = {
 	/* .dest_logical      -  default_send_IPI_ use it but we use our own. */
 	.check_apicid_used		= default_check_apicid_used, /* Used on 32-bit */
 
-	.vector_allocation_domain	= flat_vector_allocation_domain,
 	.init_apic_ldr			= xen_noop, /* setup_local_APIC calls it */
 
 	.ioapic_phys_id_map		= default_ioapic_phys_id_map, /* Used on 32-bit */
@@ -177,7 +176,6 @@ static struct apic xen_pv_apic = {
 	.get_apic_id 			= xen_get_apic_id,
 	.set_apic_id 			= xen_set_apic_id, /* Can be NULL on 32-bit. */
 
-	.cpu_mask_to_apicid		= flat_cpu_mask_to_apicid,
 	.calc_dest_apicid		= apic_flat_calc_apicid,
 
 #ifdef CONFIG_SMP