diff options
| -rw-r--r-- | arch/arm/include/asm/kvm_host.h | 4 | ||||
| -rw-r--r-- | arch/arm/kvm/arm.c | 6 | ||||
| -rw-r--r-- | arch/arm64/include/asm/kvm_asm.h | 2 | ||||
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 5 | ||||
| -rw-r--r-- | arch/arm64/kernel/asm-offsets.c | 1 | ||||
| -rw-r--r-- | arch/arm64/kvm/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/debug.c | 81 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp.S | 19 |
8 files changed, 108 insertions, 12 deletions
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index e896d2c196e6..2b0bc8c57552 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -231,4 +231,8 @@ static inline void kvm_arch_sync_events(struct kvm *kvm) {} static inline void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) {} static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} +static inline void kvm_arm_init_debug(void) {} +static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {} +static inline void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) {} + #endif /* __ARM_KVM_HOST_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 1b693cb2d5b2..77151b111d32 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -543,6 +543,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) continue; } + kvm_arm_setup_debug(vcpu); + /************************************************************** * Enter the guest */ @@ -557,6 +559,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) * Back from guest *************************************************************/ + kvm_arm_clear_debug(vcpu); + /* * We may have taken a host interrupt in HYP mode (ie * while executing the guest). This interrupt is still @@ -914,6 +918,8 @@ static void cpu_init_hyp_mode(void *dummy) vector_ptr = (unsigned long)__kvm_hyp_vector; __cpu_init_hyp_mode(boot_pgd_ptr, pgd_ptr, hyp_stack_ptr, vector_ptr); + + kvm_arm_init_debug(); } static int hyp_init_cpu_notify(struct notifier_block *self, diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index 3c5fe685a2d6..f5e40dae291a 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -132,6 +132,8 @@ extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); extern u64 __vgic_v3_get_ich_vtr_el2(void); +extern u32 __kvm_get_mdcr_el2(void); + #endif #endif /* __ARM_KVM_ASM_H__ */ diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 2709db2a7eac..c90c6a41c448 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -103,6 +103,7 @@ struct kvm_vcpu_arch { /* HYP configuration */ u64 hcr_el2; + u32 mdcr_el2; /* Exception Information */ struct kvm_vcpu_fault_info fault; @@ -227,4 +228,8 @@ static inline void kvm_arch_sync_events(struct kvm *kvm) {} static inline void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) {} static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} +void kvm_arm_init_debug(void); +void kvm_arm_setup_debug(struct kvm_vcpu *vcpu); +void kvm_arm_clear_debug(struct kvm_vcpu *vcpu); + #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index c99701a34d7b..5c900d49b906 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -117,6 +117,7 @@ int main(void) DEFINE(VCPU_HPFAR_EL2, offsetof(struct kvm_vcpu, arch.fault.hpfar_el2)); DEFINE(VCPU_DEBUG_FLAGS, offsetof(struct kvm_vcpu, arch.debug_flags)); DEFINE(VCPU_HCR_EL2, offsetof(struct kvm_vcpu, arch.hcr_el2)); + DEFINE(VCPU_MDCR_EL2, offsetof(struct kvm_vcpu, arch.mdcr_el2)); DEFINE(VCPU_IRQ_LINES, offsetof(struct kvm_vcpu, arch.irq_lines)); DEFINE(VCPU_HOST_CONTEXT, offsetof(struct kvm_vcpu, arch.host_cpu_context)); DEFINE(VCPU_TIMER_CNTV_CTL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_ctl)); diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index f90f4aa7f88d..1949fe5f5424 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -17,7 +17,7 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/psci.o $(ARM)/perf.o kvm-$(CONFIG_KVM_ARM_HOST) += emulate.o inject_fault.o regmap.o kvm-$(CONFIG_KVM_ARM_HOST) += hyp.o hyp-init.o handle_exit.o -kvm-$(CONFIG_KVM_ARM_HOST) += guest.o reset.o sys_regs.o sys_regs_generic_v8.o +kvm-$(CONFIG_KVM_ARM_HOST) += guest.o debug.o reset.o sys_regs.o sys_regs_generic_v8.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic-v2.o diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c new file mode 100644 index 000000000000..faf0e1fdba9e --- /dev/null +++ b/arch/arm64/kvm/debug.c @@ -0,0 +1,81 @@ +/* + * Debug and Guest Debug support + * + * Copyright (C) 2015 - Linaro Ltd + * Author: Alex Bennée <alex.bennee@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/kvm_host.h> + +#include <asm/kvm_arm.h> + +static DEFINE_PER_CPU(u32, mdcr_el2); + +/** + * kvm_arm_init_debug - grab what we need for debug + * + * Currently the sole task of this function is to retrieve the initial + * value of mdcr_el2 so we can preserve MDCR_EL2.HPMN which has + * presumably been set-up by some knowledgeable bootcode. + * + * It is called once per-cpu during CPU hyp initialisation. + */ + +void kvm_arm_init_debug(void) +{ + __this_cpu_write(mdcr_el2, kvm_call_hyp(__kvm_get_mdcr_el2)); +} + + +/** + * kvm_arm_setup_debug - set up debug related stuff + * + * @vcpu: the vcpu pointer + * + * This is called before each entry into the hypervisor to setup any + * debug related registers. Currently this just ensures we will trap + * access to: + * - Performance monitors (MDCR_EL2_TPM/MDCR_EL2_TPMCR) + * - Debug ROM Address (MDCR_EL2_TDRA) + * - OS related registers (MDCR_EL2_TDOSA) + * + * Additionally, KVM only traps guest accesses to the debug registers if + * the guest is not actively using them (see the KVM_ARM64_DEBUG_DIRTY + * flag on vcpu->arch.debug_flags). Since the guest must not interfere + * with the hardware state when debugging the guest, we must ensure that + * trapping is enabled whenever we are debugging the guest using the + * debug registers. + */ + +void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) +{ + bool trap_debug = !(vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY); + + vcpu->arch.mdcr_el2 = __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK; + vcpu->arch.mdcr_el2 |= (MDCR_EL2_TPM | + MDCR_EL2_TPMCR | + MDCR_EL2_TDRA | + MDCR_EL2_TDOSA); + + /* Trap on access to debug registers? */ + if (trap_debug) + vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA; + +} + +void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) +{ + /* Nothing to do yet */ +} diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S index 17a8fb14f428..b3176e6e51d1 100644 --- a/arch/arm64/kvm/hyp.S +++ b/arch/arm64/kvm/hyp.S @@ -770,17 +770,8 @@ mov x2, #(1 << 15) // Trap CP15 Cr=15 msr hstr_el2, x2 - mrs x2, mdcr_el2 - and x2, x2, #MDCR_EL2_HPMN_MASK - orr x2, x2, #(MDCR_EL2_TPM | MDCR_EL2_TPMCR) - orr x2, x2, #(MDCR_EL2_TDRA | MDCR_EL2_TDOSA) - - // Check for KVM_ARM64_DEBUG_DIRTY, and set debug to trap - // if not dirty. - ldr x3, [x0, #VCPU_DEBUG_FLAGS] - tbnz x3, #KVM_ARM64_DEBUG_DIRTY_SHIFT, 1f - orr x2, x2, #MDCR_EL2_TDA -1: + // Monitor Debug Config - see kvm_arm_setup_debug() + ldr x2, [x0, #VCPU_MDCR_EL2] msr mdcr_el2, x2 .endm @@ -1285,4 +1276,10 @@ ENTRY(__kvm_hyp_vector) ventry el1_error_invalid // Error 32-bit EL1 ENDPROC(__kvm_hyp_vector) + +ENTRY(__kvm_get_mdcr_el2) + mrs x0, mdcr_el2 + ret +ENDPROC(__kvm_get_mdcr_el2) + .popsection |