Merge tag 'kvm-arm-for-4.3-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master

Second set of KVM/ARM changes for 4.3-rc2

- Workaround for a Cortex-A57 erratum
- Bug fix for the debugging infrastructure
- Fix for 32bit guests with more than 4GB of address space
  on a 32bit host
- A number of fixes for the (unusual) case when we don't use
  the in-kernel GIC emulation
- Removal of ThumbEE handling on arm64, since these have been
  dropped from the architecture before anyone actually ever
  built a CPU
- Remove the KVM_ARM_MAX_VCPUS limitation which has become
  fairly pointless

arch/arm/include/asm/kvm_host.h

@@ -29,12 +29,6 @@
 
 #define __KVM_HAVE_ARCH_INTC_INITIALIZED
 
-#if defined(CONFIG_KVM_ARM_MAX_VCPUS)
-#define KVM_MAX_VCPUS CONFIG_KVM_ARM_MAX_VCPUS
-#else
-#define KVM_MAX_VCPUS 0
-#endif
-
 #define KVM_USER_MEM_SLOTS 32
 #define KVM_PRIVATE_MEM_SLOTS 4
 #define KVM_COALESCED_MMIO_PAGE_OFFSET 1
@@ -44,6 +38,8 @@
 
 #include <kvm/arm_vgic.h>
 
+#define KVM_MAX_VCPUS VGIC_V2_MAX_CPUS
+
 u32 *kvm_vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num, u32 mode);
 int __attribute_const__ kvm_target_cpu(void);
 int kvm_reset_vcpu(struct kvm_vcpu *vcpu);

arch/arm/kvm/Kconfig

@@ -45,15 +45,4 @@ config KVM_ARM_HOST
 	---help---
 	  Provides host support for ARM processors.
 
-config KVM_ARM_MAX_VCPUS
-	int "Number maximum supported virtual CPUs per VM"
-	depends on KVM_ARM_HOST
-	default 4
-	help
-	  Static number of max supported virtual CPUs per VM.
-
-	  If you choose a high number, the vcpu structures will be quite
-	  large, so only choose a reasonable number that you expect to
-	  actually use.
-
 endif # VIRTUALIZATION

arch/arm/kvm/arm.c

@@ -446,7 +446,7 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu)
 	 * Map the VGIC hardware resources before running a vcpu the first
 	 * time on this VM.
 	 */
-	if (unlikely(!vgic_ready(kvm))) {
+	if (unlikely(irqchip_in_kernel(kvm) && !vgic_ready(kvm))) {
 		ret = kvm_vgic_map_resources(kvm);
 		if (ret)
 			return ret;

arch/arm/kvm/interrupts_head.S

@@ -515,8 +515,7 @@ ARM_BE8(rev	r6, r6  )
 
 	mrc	p15, 0, r2, c14, c3, 1	@ CNTV_CTL
 	str	r2, [vcpu, #VCPU_TIMER_CNTV_CTL]
-	bic	r2, #1			@ Clear ENABLE
-	mcr	p15, 0, r2, c14, c3, 1	@ CNTV_CTL
+
 	isb
 
 	mrrc	p15, 3, rr_lo_hi(r2, r3), c14	@ CNTV_CVAL
@@ -529,6 +528,9 @@ ARM_BE8(rev	r6, r6  )
 	mcrr	p15, 4, r2, r2, c14	@ CNTVOFF
 
 1:
+	mov	r2, #0			@ Clear ENABLE
+	mcr	p15, 0, r2, c14, c3, 1	@ CNTV_CTL
+
 	@ Allow physical timer/counter access for the host
 	mrc	p15, 4, r2, c14, c1, 0	@ CNTHCTL
 	orr	r2, r2, #(CNTHCTL_PL1PCEN | CNTHCTL_PL1PCTEN)

arch/arm/kvm/mmu.c

@@ -1792,8 +1792,10 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
 		if (vma->vm_flags & VM_PFNMAP) {
 			gpa_t gpa = mem->guest_phys_addr +
 				    (vm_start - mem->userspace_addr);
-			phys_addr_t pa = (vma->vm_pgoff << PAGE_SHIFT) +
-					 vm_start - vma->vm_start;
+			phys_addr_t pa;
+
+			pa = (phys_addr_t)vma->vm_pgoff << PAGE_SHIFT;
+			pa += vm_start - vma->vm_start;
 
 			/* IO region dirty page logging not allowed */
 			if (memslot->flags & KVM_MEM_LOG_DIRTY_PAGES)

arch/arm64/include/asm/kvm_arm.h

@@ -172,7 +172,6 @@
 #define VTTBR_VMID_MASK	  (UL(0xFF) << VTTBR_VMID_SHIFT)
 
 /* Hyp System Trap Register */
-#define HSTR_EL2_TTEE	(1 << 16)
 #define HSTR_EL2_T(x)	(1 << x)
 
 /* Hyp Coproccessor Trap Register Shifts */

arch/arm64/include/asm/kvm_asm.h

@@ -53,9 +53,7 @@
 #define	IFSR32_EL2	25	/* Instruction Fault Status Register */
 #define	FPEXC32_EL2	26	/* Floating-Point Exception Control Register */
 #define	DBGVCR32_EL2	27	/* Debug Vector Catch Register */
-#define	TEECR32_EL1	28	/* ThumbEE Configuration Register */
-#define	TEEHBR32_EL1	29	/* ThumbEE Handler Base Register */
-#define	NR_SYS_REGS	30
+#define	NR_SYS_REGS	28
 
 /* 32bit mapping */
 #define c0_MPIDR	(MPIDR_EL1 * 2)	/* MultiProcessor ID Register */

arch/arm64/include/asm/kvm_host.h

@@ -30,12 +30,6 @@
 
 #define __KVM_HAVE_ARCH_INTC_INITIALIZED
 
-#if defined(CONFIG_KVM_ARM_MAX_VCPUS)
-#define KVM_MAX_VCPUS CONFIG_KVM_ARM_MAX_VCPUS
-#else
-#define KVM_MAX_VCPUS 0
-#endif
-
 #define KVM_USER_MEM_SLOTS 32
 #define KVM_PRIVATE_MEM_SLOTS 4
 #define KVM_COALESCED_MMIO_PAGE_OFFSET 1
@@ -43,6 +37,8 @@
 #include <kvm/arm_vgic.h>
 #include <kvm/arm_arch_timer.h>
 
+#define KVM_MAX_VCPUS VGIC_V3_MAX_CPUS
+
 #define KVM_VCPU_MAX_FEATURES 3
 
 int __attribute_const__ kvm_target_cpu(void);

arch/arm64/kvm/Kconfig

@@ -41,15 +41,4 @@ config KVM_ARM_HOST
 	---help---
 	  Provides host support for ARM processors.
 
-config KVM_ARM_MAX_VCPUS
-	int "Number maximum supported virtual CPUs per VM"
-	depends on KVM_ARM_HOST
-	default 4
-	help
-	  Static number of max supported virtual CPUs per VM.
-
-	  If you choose a high number, the vcpu structures will be quite
-	  large, so only choose a reasonable number that you expect to
-	  actually use.
-
 endif # VIRTUALIZATION

arch/arm64/kvm/hyp.S

@@ -433,20 +433,13 @@
 	mrs	x5, ifsr32_el2
 	stp	x4, x5, [x3]
 
-	skip_fpsimd_state x8, 3f
+	skip_fpsimd_state x8, 2f
 	mrs	x6, fpexc32_el2
 	str	x6, [x3, #16]
-3:
-	skip_debug_state x8, 2f
+2:
+	skip_debug_state x8, 1f
 	mrs	x7, dbgvcr32_el2
 	str	x7, [x3, #24]
-2:
-	skip_tee_state x8, 1f
-
-	add	x3, x2, #CPU_SYSREG_OFFSET(TEECR32_EL1)
-	mrs	x4, teecr32_el1
-	mrs	x5, teehbr32_el1
-	stp	x4, x5, [x3]
 1:
 .endm
 
@@ -466,16 +459,9 @@
 	msr	dacr32_el2, x4
 	msr	ifsr32_el2, x5
 
-	skip_debug_state x8, 2f
+	skip_debug_state x8, 1f
 	ldr	x7, [x3, #24]
 	msr	dbgvcr32_el2, x7
-2:
-	skip_tee_state x8, 1f
-
-	add	x3, x2, #CPU_SYSREG_OFFSET(TEECR32_EL1)
-	ldp	x4, x5, [x3]
-	msr	teecr32_el1, x4
-	msr	teehbr32_el1, x5
 1:
 .endm
 
@@ -570,8 +556,6 @@ alternative_endif
 	mrs	x3, cntv_ctl_el0
 	and	x3, x3, #3
 	str	w3, [x0, #VCPU_TIMER_CNTV_CTL]
-	bic	x3, x3, #1		// Clear Enable
-	msr	cntv_ctl_el0, x3
 
 	isb
 
@@ -579,6 +563,9 @@ alternative_endif
 	str	x3, [x0, #VCPU_TIMER_CNTV_CVAL]
 
 1:
+	// Disable the virtual timer
+	msr	cntv_ctl_el0, xzr
+
 	// Allow physical timer/counter access for the host
 	mrs	x2, cnthctl_el2
 	orr	x2, x2, #3
@@ -753,6 +740,9 @@ ENTRY(__kvm_vcpu_run)
 	// Guest context
 	add	x2, x0, #VCPU_CONTEXT
 
+	// We must restore the 32-bit state before the sysregs, thanks
+	// to Cortex-A57 erratum #852523.
+	restore_guest_32bit_state
 	bl __restore_sysregs
 
 	skip_debug_state x3, 1f
@@ -760,7 +750,6 @@ ENTRY(__kvm_vcpu_run)
 	kern_hyp_va x3
 	bl	__restore_debug
 1:
-	restore_guest_32bit_state
 	restore_guest_regs
 
 	// That's it, no more messing around.

arch/arm64/kvm/sys_regs.c

@@ -272,7 +272,7 @@ static int set_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
 {
 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg];
 
-	if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
+	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
 		return -EFAULT;
 	return 0;
 }
@@ -314,7 +314,7 @@ static int set_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
 {
 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg];
 
-	if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
+	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
 		return -EFAULT;
 
 	return 0;
@@ -358,7 +358,7 @@ static int set_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
 {
 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg];
 
-	if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
+	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
 		return -EFAULT;
 	return 0;
 }
@@ -400,7 +400,7 @@ static int set_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
 {
 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg];
 
-	if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
+	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
 		return -EFAULT;
 	return 0;
 }
@@ -539,13 +539,6 @@ static const struct sys_reg_desc sys_reg_descs[] = {
 	{ Op0(0b10), Op1(0b000), CRn(0b0111), CRm(0b1110), Op2(0b110),
 	  trap_dbgauthstatus_el1 },
 
-	/* TEECR32_EL1 */
-	{ Op0(0b10), Op1(0b010), CRn(0b0000), CRm(0b0000), Op2(0b000),
-	  NULL, reset_val, TEECR32_EL1, 0 },
-	/* TEEHBR32_EL1 */
-	{ Op0(0b10), Op1(0b010), CRn(0b0001), CRm(0b0000), Op2(0b000),
-	  NULL, reset_val, TEEHBR32_EL1, 0 },
-
 	/* MDCCSR_EL1 */
 	{ Op0(0b10), Op1(0b011), CRn(0b0000), CRm(0b0001), Op2(0b000),
 	  trap_raz_wi },

include/kvm/arm_vgic.h

@@ -35,11 +35,7 @@
 #define VGIC_V3_MAX_LRS		16
 #define VGIC_MAX_IRQS		1024
 #define VGIC_V2_MAX_CPUS	8
-
-/* Sanity checks... */
-#if (KVM_MAX_VCPUS > 255)
-#error Too many KVM VCPUs, the VGIC only supports up to 255 VCPUs for now
-#endif
+#define VGIC_V3_MAX_CPUS	255
 
 #if (VGIC_NR_IRQS_LEGACY & 31)
 #error "VGIC_NR_IRQS must be a multiple of 32"

virt/kvm/arm/vgic-v3.c

@@ -288,7 +288,7 @@ int vgic_v3_probe(struct device_node *vgic_node,
 
 	vgic->vctrl_base = NULL;
 	vgic->type = VGIC_V3;
-	vgic->max_gic_vcpus = KVM_MAX_VCPUS;
+	vgic->max_gic_vcpus = VGIC_V3_MAX_CPUS;
 
 	kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
 		 vcpu_res.start, vgic->maint_irq);