[GIT PULL 10/51] KVM: arm/arm64: vgic: move GICv2 registers to their own structure

Christoffer Dall christoffer.dall at linaro.org
Mon Aug 4 01:46:27 PDT 2014


From: Marc Zyngier <marc.zyngier at arm.com>

In order to make way for the GICv3 registers, move the v2-specific
registers to their own structure.

Acked-by: Catalin Marinas <catalin.marinas at arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall at linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
 arch/arm/kernel/asm-offsets.c   | 14 +++++------
 arch/arm/kvm/interrupts_head.S  | 26 +++++++++----------
 arch/arm64/kernel/asm-offsets.c | 14 +++++------
 arch/arm64/kvm/hyp.S            | 26 +++++++++----------
 include/kvm/arm_vgic.h          | 20 +++++++++------
 virt/kvm/arm/vgic.c             | 56 ++++++++++++++++++++---------------------
 6 files changed, 81 insertions(+), 75 deletions(-)

diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index 85598b5..713e807 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -182,13 +182,13 @@ int main(void)
   DEFINE(VCPU_HYP_PC,		offsetof(struct kvm_vcpu, arch.fault.hyp_pc));
 #ifdef CONFIG_KVM_ARM_VGIC
   DEFINE(VCPU_VGIC_CPU,		offsetof(struct kvm_vcpu, arch.vgic_cpu));
-  DEFINE(VGIC_CPU_HCR,		offsetof(struct vgic_cpu, vgic_hcr));
-  DEFINE(VGIC_CPU_VMCR,		offsetof(struct vgic_cpu, vgic_vmcr));
-  DEFINE(VGIC_CPU_MISR,		offsetof(struct vgic_cpu, vgic_misr));
-  DEFINE(VGIC_CPU_EISR,		offsetof(struct vgic_cpu, vgic_eisr));
-  DEFINE(VGIC_CPU_ELRSR,	offsetof(struct vgic_cpu, vgic_elrsr));
-  DEFINE(VGIC_CPU_APR,		offsetof(struct vgic_cpu, vgic_apr));
-  DEFINE(VGIC_CPU_LR,		offsetof(struct vgic_cpu, vgic_lr));
+  DEFINE(VGIC_V2_CPU_HCR,	offsetof(struct vgic_cpu, vgic_v2.vgic_hcr));
+  DEFINE(VGIC_V2_CPU_VMCR,	offsetof(struct vgic_cpu, vgic_v2.vgic_vmcr));
+  DEFINE(VGIC_V2_CPU_MISR,	offsetof(struct vgic_cpu, vgic_v2.vgic_misr));
+  DEFINE(VGIC_V2_CPU_EISR,	offsetof(struct vgic_cpu, vgic_v2.vgic_eisr));
+  DEFINE(VGIC_V2_CPU_ELRSR,	offsetof(struct vgic_cpu, vgic_v2.vgic_elrsr));
+  DEFINE(VGIC_V2_CPU_APR,	offsetof(struct vgic_cpu, vgic_v2.vgic_apr));
+  DEFINE(VGIC_V2_CPU_LR,	offsetof(struct vgic_cpu, vgic_v2.vgic_lr));
   DEFINE(VGIC_CPU_NR_LR,	offsetof(struct vgic_cpu, nr_lr));
 #ifdef CONFIG_KVM_ARM_TIMER
   DEFINE(VCPU_TIMER_CNTV_CTL,	offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_ctl));
diff --git a/arch/arm/kvm/interrupts_head.S b/arch/arm/kvm/interrupts_head.S
index 76af9302..e4eaf30 100644
--- a/arch/arm/kvm/interrupts_head.S
+++ b/arch/arm/kvm/interrupts_head.S
@@ -421,14 +421,14 @@ vcpu	.req	r0		@ vcpu pointer always in r0
 	ldr	r9, [r2, #GICH_ELRSR1]
 	ldr	r10, [r2, #GICH_APR]
 
-	str	r3, [r11, #VGIC_CPU_HCR]
-	str	r4, [r11, #VGIC_CPU_VMCR]
-	str	r5, [r11, #VGIC_CPU_MISR]
-	str	r6, [r11, #VGIC_CPU_EISR]
-	str	r7, [r11, #(VGIC_CPU_EISR + 4)]
-	str	r8, [r11, #VGIC_CPU_ELRSR]
-	str	r9, [r11, #(VGIC_CPU_ELRSR + 4)]
-	str	r10, [r11, #VGIC_CPU_APR]
+	str	r3, [r11, #VGIC_V2_CPU_HCR]
+	str	r4, [r11, #VGIC_V2_CPU_VMCR]
+	str	r5, [r11, #VGIC_V2_CPU_MISR]
+	str	r6, [r11, #VGIC_V2_CPU_EISR]
+	str	r7, [r11, #(VGIC_V2_CPU_EISR + 4)]
+	str	r8, [r11, #VGIC_V2_CPU_ELRSR]
+	str	r9, [r11, #(VGIC_V2_CPU_ELRSR + 4)]
+	str	r10, [r11, #VGIC_V2_CPU_APR]
 
 	/* Clear GICH_HCR */
 	mov	r5, #0
@@ -436,7 +436,7 @@ vcpu	.req	r0		@ vcpu pointer always in r0
 
 	/* Save list registers */
 	add	r2, r2, #GICH_LR0
-	add	r3, r11, #VGIC_CPU_LR
+	add	r3, r11, #VGIC_V2_CPU_LR
 	ldr	r4, [r11, #VGIC_CPU_NR_LR]
 1:	ldr	r6, [r2], #4
 	str	r6, [r3], #4
@@ -463,9 +463,9 @@ vcpu	.req	r0		@ vcpu pointer always in r0
 	add	r11, vcpu, #VCPU_VGIC_CPU
 
 	/* We only restore a minimal set of registers */
-	ldr	r3, [r11, #VGIC_CPU_HCR]
-	ldr	r4, [r11, #VGIC_CPU_VMCR]
-	ldr	r8, [r11, #VGIC_CPU_APR]
+	ldr	r3, [r11, #VGIC_V2_CPU_HCR]
+	ldr	r4, [r11, #VGIC_V2_CPU_VMCR]
+	ldr	r8, [r11, #VGIC_V2_CPU_APR]
 
 	str	r3, [r2, #GICH_HCR]
 	str	r4, [r2, #GICH_VMCR]
@@ -473,7 +473,7 @@ vcpu	.req	r0		@ vcpu pointer always in r0
 
 	/* Restore list registers */
 	add	r2, r2, #GICH_LR0
-	add	r3, r11, #VGIC_CPU_LR
+	add	r3, r11, #VGIC_V2_CPU_LR
 	ldr	r4, [r11, #VGIC_CPU_NR_LR]
 1:	ldr	r6, [r3], #4
 	str	r6, [r2], #4
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index 646f888..20fd488 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -129,13 +129,13 @@ int main(void)
   DEFINE(KVM_TIMER_ENABLED,	offsetof(struct kvm, arch.timer.enabled));
   DEFINE(VCPU_KVM,		offsetof(struct kvm_vcpu, kvm));
   DEFINE(VCPU_VGIC_CPU,		offsetof(struct kvm_vcpu, arch.vgic_cpu));
-  DEFINE(VGIC_CPU_HCR,		offsetof(struct vgic_cpu, vgic_hcr));
-  DEFINE(VGIC_CPU_VMCR,		offsetof(struct vgic_cpu, vgic_vmcr));
-  DEFINE(VGIC_CPU_MISR,		offsetof(struct vgic_cpu, vgic_misr));
-  DEFINE(VGIC_CPU_EISR,		offsetof(struct vgic_cpu, vgic_eisr));
-  DEFINE(VGIC_CPU_ELRSR,	offsetof(struct vgic_cpu, vgic_elrsr));
-  DEFINE(VGIC_CPU_APR,		offsetof(struct vgic_cpu, vgic_apr));
-  DEFINE(VGIC_CPU_LR,		offsetof(struct vgic_cpu, vgic_lr));
+  DEFINE(VGIC_V2_CPU_HCR,	offsetof(struct vgic_cpu, vgic_v2.vgic_hcr));
+  DEFINE(VGIC_V2_CPU_VMCR,	offsetof(struct vgic_cpu, vgic_v2.vgic_vmcr));
+  DEFINE(VGIC_V2_CPU_MISR,	offsetof(struct vgic_cpu, vgic_v2.vgic_misr));
+  DEFINE(VGIC_V2_CPU_EISR,	offsetof(struct vgic_cpu, vgic_v2.vgic_eisr));
+  DEFINE(VGIC_V2_CPU_ELRSR,	offsetof(struct vgic_cpu, vgic_v2.vgic_elrsr));
+  DEFINE(VGIC_V2_CPU_APR,	offsetof(struct vgic_cpu, vgic_v2.vgic_apr));
+  DEFINE(VGIC_V2_CPU_LR,	offsetof(struct vgic_cpu, vgic_v2.vgic_lr));
   DEFINE(VGIC_CPU_NR_LR,	offsetof(struct vgic_cpu, nr_lr));
   DEFINE(KVM_VTTBR,		offsetof(struct kvm, arch.vttbr));
   DEFINE(KVM_VGIC_VCTRL,	offsetof(struct kvm, arch.vgic.vctrl_base));
diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
index b0d1512..877d82a1 100644
--- a/arch/arm64/kvm/hyp.S
+++ b/arch/arm64/kvm/hyp.S
@@ -412,14 +412,14 @@ CPU_BE(	rev	w9,  w9  )
 CPU_BE(	rev	w10, w10 )
 CPU_BE(	rev	w11, w11 )
 
-	str	w4, [x3, #VGIC_CPU_HCR]
-	str	w5, [x3, #VGIC_CPU_VMCR]
-	str	w6, [x3, #VGIC_CPU_MISR]
-	str	w7, [x3, #VGIC_CPU_EISR]
-	str	w8, [x3, #(VGIC_CPU_EISR + 4)]
-	str	w9, [x3, #VGIC_CPU_ELRSR]
-	str	w10, [x3, #(VGIC_CPU_ELRSR + 4)]
-	str	w11, [x3, #VGIC_CPU_APR]
+	str	w4, [x3, #VGIC_V2_CPU_HCR]
+	str	w5, [x3, #VGIC_V2_CPU_VMCR]
+	str	w6, [x3, #VGIC_V2_CPU_MISR]
+	str	w7, [x3, #VGIC_V2_CPU_EISR]
+	str	w8, [x3, #(VGIC_V2_CPU_EISR + 4)]
+	str	w9, [x3, #VGIC_V2_CPU_ELRSR]
+	str	w10, [x3, #(VGIC_V2_CPU_ELRSR + 4)]
+	str	w11, [x3, #VGIC_V2_CPU_APR]
 
 	/* Clear GICH_HCR */
 	str	wzr, [x2, #GICH_HCR]
@@ -427,7 +427,7 @@ CPU_BE(	rev	w11, w11 )
 	/* Save list registers */
 	add	x2, x2, #GICH_LR0
 	ldr	w4, [x3, #VGIC_CPU_NR_LR]
-	add	x3, x3, #VGIC_CPU_LR
+	add	x3, x3, #VGIC_V2_CPU_LR
 1:	ldr	w5, [x2], #4
 CPU_BE(	rev	w5, w5 )
 	str	w5, [x3], #4
@@ -452,9 +452,9 @@ CPU_BE(	rev	w5, w5 )
 	add	x3, x0, #VCPU_VGIC_CPU
 
 	/* We only restore a minimal set of registers */
-	ldr	w4, [x3, #VGIC_CPU_HCR]
-	ldr	w5, [x3, #VGIC_CPU_VMCR]
-	ldr	w6, [x3, #VGIC_CPU_APR]
+	ldr	w4, [x3, #VGIC_V2_CPU_HCR]
+	ldr	w5, [x3, #VGIC_V2_CPU_VMCR]
+	ldr	w6, [x3, #VGIC_V2_CPU_APR]
 CPU_BE(	rev	w4, w4 )
 CPU_BE(	rev	w5, w5 )
 CPU_BE(	rev	w6, w6 )
@@ -466,7 +466,7 @@ CPU_BE(	rev	w6, w6 )
 	/* Restore list registers */
 	add	x2, x2, #GICH_LR0
 	ldr	w4, [x3, #VGIC_CPU_NR_LR]
-	add	x3, x3, #VGIC_CPU_LR
+	add	x3, x3, #VGIC_V2_CPU_LR
 1:	ldr	w5, [x3], #4
 CPU_BE(	rev	w5, w5 )
 	str	w5, [x2], #4
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index f27000f..f738e5a 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -110,6 +110,16 @@ struct vgic_dist {
 #endif
 };
 
+struct vgic_v2_cpu_if {
+	u32		vgic_hcr;
+	u32		vgic_vmcr;
+	u32		vgic_misr;	/* Saved only */
+	u32		vgic_eisr[2];	/* Saved only */
+	u32		vgic_elrsr[2];	/* Saved only */
+	u32		vgic_apr;
+	u32		vgic_lr[VGIC_MAX_LRS];
+};
+
 struct vgic_cpu {
 #ifdef CONFIG_KVM_ARM_VGIC
 	/* per IRQ to LR mapping */
@@ -126,13 +136,9 @@ struct vgic_cpu {
 	int		nr_lr;
 
 	/* CPU vif control registers for world switch */
-	u32		vgic_hcr;
-	u32		vgic_vmcr;
-	u32		vgic_misr;	/* Saved only */
-	u32		vgic_eisr[2];	/* Saved only */
-	u32		vgic_elrsr[2];	/* Saved only */
-	u32		vgic_apr;
-	u32		vgic_lr[VGIC_MAX_LRS];
+	union {
+		struct vgic_v2_cpu_if	vgic_v2;
+	};
 #endif
 };
 
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 56ff9be..0ba1ab0 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -601,7 +601,7 @@ static bool handle_mmio_sgi_reg(struct kvm_vcpu *vcpu,
 static void vgic_retire_lr(int lr_nr, int irq, struct vgic_cpu *vgic_cpu)
 {
 	clear_bit(lr_nr, vgic_cpu->lr_used);
-	vgic_cpu->vgic_lr[lr_nr] &= ~GICH_LR_STATE;
+	vgic_cpu->vgic_v2.vgic_lr[lr_nr] &= ~GICH_LR_STATE;
 	vgic_cpu->vgic_irq_lr_map[irq] = LR_EMPTY;
 }
 
@@ -626,7 +626,7 @@ static void vgic_unqueue_irqs(struct kvm_vcpu *vcpu)
 	u32 *lr;
 
 	for_each_set_bit(i, vgic_cpu->lr_used, vgic_cpu->nr_lr) {
-		lr = &vgic_cpu->vgic_lr[i];
+		lr = &vgic_cpu->vgic_v2.vgic_lr[i];
 		irq = LR_IRQID(*lr);
 		source_cpu = LR_CPUID(*lr);
 
@@ -1007,7 +1007,7 @@ static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu)
 	int lr;
 
 	for_each_set_bit(lr, vgic_cpu->lr_used, vgic_cpu->nr_lr) {
-		int irq = vgic_cpu->vgic_lr[lr] & GICH_LR_VIRTUALID;
+		int irq = vgic_cpu->vgic_v2.vgic_lr[lr] & GICH_LR_VIRTUALID;
 
 		if (!vgic_irq_is_enabled(vcpu, irq)) {
 			vgic_retire_lr(lr, irq, vgic_cpu);
@@ -1037,11 +1037,11 @@ static bool vgic_queue_irq(struct kvm_vcpu *vcpu, u8 sgi_source_id, int irq)
 
 	/* Do we have an active interrupt for the same CPUID? */
 	if (lr != LR_EMPTY &&
-	    (LR_CPUID(vgic_cpu->vgic_lr[lr]) == sgi_source_id)) {
+	    (LR_CPUID(vgic_cpu->vgic_v2.vgic_lr[lr]) == sgi_source_id)) {
 		kvm_debug("LR%d piggyback for IRQ%d %x\n",
-			  lr, irq, vgic_cpu->vgic_lr[lr]);
+			  lr, irq, vgic_cpu->vgic_v2.vgic_lr[lr]);
 		BUG_ON(!test_bit(lr, vgic_cpu->lr_used));
-		vgic_cpu->vgic_lr[lr] |= GICH_LR_PENDING_BIT;
+		vgic_cpu->vgic_v2.vgic_lr[lr] |= GICH_LR_PENDING_BIT;
 		return true;
 	}
 
@@ -1052,12 +1052,12 @@ static bool vgic_queue_irq(struct kvm_vcpu *vcpu, u8 sgi_source_id, int irq)
 		return false;
 
 	kvm_debug("LR%d allocated for IRQ%d %x\n", lr, irq, sgi_source_id);
-	vgic_cpu->vgic_lr[lr] = MK_LR_PEND(sgi_source_id, irq);
+	vgic_cpu->vgic_v2.vgic_lr[lr] = MK_LR_PEND(sgi_source_id, irq);
 	vgic_cpu->vgic_irq_lr_map[irq] = lr;
 	set_bit(lr, vgic_cpu->lr_used);
 
 	if (!vgic_irq_is_edge(vcpu, irq))
-		vgic_cpu->vgic_lr[lr] |= GICH_LR_EOI;
+		vgic_cpu->vgic_v2.vgic_lr[lr] |= GICH_LR_EOI;
 
 	return true;
 }
@@ -1155,9 +1155,9 @@ static void __kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
 
 epilog:
 	if (overflow) {
-		vgic_cpu->vgic_hcr |= GICH_HCR_UIE;
+		vgic_cpu->vgic_v2.vgic_hcr |= GICH_HCR_UIE;
 	} else {
-		vgic_cpu->vgic_hcr &= ~GICH_HCR_UIE;
+		vgic_cpu->vgic_v2.vgic_hcr &= ~GICH_HCR_UIE;
 		/*
 		 * We're about to run this VCPU, and we've consumed
 		 * everything the distributor had in store for
@@ -1173,21 +1173,21 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu)
 	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
 	bool level_pending = false;
 
-	kvm_debug("MISR = %08x\n", vgic_cpu->vgic_misr);
+	kvm_debug("MISR = %08x\n", vgic_cpu->vgic_v2.vgic_misr);
 
-	if (vgic_cpu->vgic_misr & GICH_MISR_EOI) {
+	if (vgic_cpu->vgic_v2.vgic_misr & GICH_MISR_EOI) {
 		/*
 		 * Some level interrupts have been EOIed. Clear their
 		 * active bit.
 		 */
 		int lr, irq;
 
-		for_each_set_bit(lr, (unsigned long *)vgic_cpu->vgic_eisr,
+		for_each_set_bit(lr, (unsigned long *)vgic_cpu->vgic_v2.vgic_eisr,
 				 vgic_cpu->nr_lr) {
-			irq = vgic_cpu->vgic_lr[lr] & GICH_LR_VIRTUALID;
+			irq = vgic_cpu->vgic_v2.vgic_lr[lr] & GICH_LR_VIRTUALID;
 
 			vgic_irq_clear_active(vcpu, irq);
-			vgic_cpu->vgic_lr[lr] &= ~GICH_LR_EOI;
+			vgic_cpu->vgic_v2.vgic_lr[lr] &= ~GICH_LR_EOI;
 
 			/* Any additional pending interrupt? */
 			if (vgic_dist_irq_is_pending(vcpu, irq)) {
@@ -1201,13 +1201,13 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu)
 			 * Despite being EOIed, the LR may not have
 			 * been marked as empty.
 			 */
-			set_bit(lr, (unsigned long *)vgic_cpu->vgic_elrsr);
-			vgic_cpu->vgic_lr[lr] &= ~GICH_LR_ACTIVE_BIT;
+			set_bit(lr, (unsigned long *)vgic_cpu->vgic_v2.vgic_elrsr);
+			vgic_cpu->vgic_v2.vgic_lr[lr] &= ~GICH_LR_ACTIVE_BIT;
 		}
 	}
 
-	if (vgic_cpu->vgic_misr & GICH_MISR_U)
-		vgic_cpu->vgic_hcr &= ~GICH_HCR_UIE;
+	if (vgic_cpu->vgic_v2.vgic_misr & GICH_MISR_U)
+		vgic_cpu->vgic_v2.vgic_hcr &= ~GICH_HCR_UIE;
 
 	return level_pending;
 }
@@ -1226,21 +1226,21 @@ static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
 	level_pending = vgic_process_maintenance(vcpu);
 
 	/* Clear mappings for empty LRs */
-	for_each_set_bit(lr, (unsigned long *)vgic_cpu->vgic_elrsr,
+	for_each_set_bit(lr, (unsigned long *)vgic_cpu->vgic_v2.vgic_elrsr,
 			 vgic_cpu->nr_lr) {
 		int irq;
 
 		if (!test_and_clear_bit(lr, vgic_cpu->lr_used))
 			continue;
 
-		irq = vgic_cpu->vgic_lr[lr] & GICH_LR_VIRTUALID;
+		irq = vgic_cpu->vgic_v2.vgic_lr[lr] & GICH_LR_VIRTUALID;
 
 		BUG_ON(irq >= VGIC_NR_IRQS);
 		vgic_cpu->vgic_irq_lr_map[irq] = LR_EMPTY;
 	}
 
 	/* Check if we still have something up our sleeve... */
-	pending = find_first_zero_bit((unsigned long *)vgic_cpu->vgic_elrsr,
+	pending = find_first_zero_bit((unsigned long *)vgic_cpu->vgic_v2.vgic_elrsr,
 				      vgic_cpu->nr_lr);
 	if (level_pending || pending < vgic_cpu->nr_lr)
 		set_bit(vcpu->vcpu_id, &dist->irq_pending_on_cpu);
@@ -1436,10 +1436,10 @@ int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
 	 * points to their reset values. Anything else resets to zero
 	 * anyway.
 	 */
-	vgic_cpu->vgic_vmcr = 0;
+	vgic_cpu->vgic_v2.vgic_vmcr = 0;
 
 	vgic_cpu->nr_lr = vgic_nr_lr;
-	vgic_cpu->vgic_hcr = GICH_HCR_EN; /* Get the show on the road... */
+	vgic_cpu->vgic_v2.vgic_hcr = GICH_HCR_EN; /* Get the show on the road... */
 
 	return 0;
 }
@@ -1746,15 +1746,15 @@ static bool handle_cpu_mmio_misc(struct kvm_vcpu *vcpu,
 	}
 
 	if (!mmio->is_write) {
-		reg = (vgic_cpu->vgic_vmcr & mask) >> shift;
+		reg = (vgic_cpu->vgic_v2.vgic_vmcr & mask) >> shift;
 		mmio_data_write(mmio, ~0, reg);
 	} else {
 		reg = mmio_data_read(mmio, ~0);
 		reg = (reg << shift) & mask;
-		if (reg != (vgic_cpu->vgic_vmcr & mask))
+		if (reg != (vgic_cpu->vgic_v2.vgic_vmcr & mask))
 			updated = true;
-		vgic_cpu->vgic_vmcr &= ~mask;
-		vgic_cpu->vgic_vmcr |= reg;
+		vgic_cpu->vgic_v2.vgic_vmcr &= ~mask;
+		vgic_cpu->vgic_v2.vgic_vmcr |= reg;
 	}
 	return updated;
 }
-- 
2.0.0




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