diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-10 16:42:49 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-10 16:42:49 -0700 |
commit | 519f526d391b0ef775aeb04c4b6f632ea6b3ee50 (patch) | |
tree | 36985d7882734c136fc3c9a48e9d9abf9e97c1f1 /arch/arm64 | |
parent | 06ab838c2024db468855118087db16d8fa905ddc (diff) | |
parent | ba60c41ae392b473a1897faa0b8739fcb8759d69 (diff) |
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more kvm updates from Paolo Bonzini:
"ARM:
- Full debug support for arm64
- Active state switching for timer interrupts
- Lazy FP/SIMD save/restore for arm64
- Generic ARMv8 target
PPC:
- Book3S: A few bug fixes
- Book3S: Allow micro-threading on POWER8
x86:
- Compiler warnings
Generic:
- Adaptive polling for guest halt"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (49 commits)
kvm: irqchip: fix memory leak
kvm: move new trace event outside #ifdef CONFIG_KVM_ASYNC_PF
KVM: trace kvm_halt_poll_ns grow/shrink
KVM: dynamic halt-polling
KVM: make halt_poll_ns per-vCPU
Silence compiler warning in arch/x86/kvm/emulate.c
kvm: compile process_smi_save_seg_64() only for x86_64
KVM: x86: avoid uninitialized variable warning
KVM: PPC: Book3S: Fix typo in top comment about locking
KVM: PPC: Book3S: Fix size of the PSPB register
KVM: PPC: Book3S HV: Exit on H_DOORBELL if HOST_IPI is set
KVM: PPC: Book3S HV: Fix race in starting secondary threads
KVM: PPC: Book3S: correct width in XER handling
KVM: PPC: Book3S HV: Fix preempted vcore stolen time calculation
KVM: PPC: Book3S HV: Fix preempted vcore list locking
KVM: PPC: Book3S HV: Implement H_CLEAR_REF and H_CLEAR_MOD
KVM: PPC: Book3S HV: Fix bug in dirty page tracking
KVM: PPC: Book3S HV: Fix race in reading change bit when removing HPTE
KVM: PPC: Book3S HV: Implement dynamic micro-threading on POWER8
KVM: PPC: Book3S HV: Make use of unused threads when running guests
...
Diffstat (limited to 'arch/arm64')
-rw-r--r-- | arch/arm64/include/asm/hw_breakpoint.h | 14 | ||||
-rw-r--r-- | arch/arm64/include/asm/kvm_arm.h | 5 | ||||
-rw-r--r-- | arch/arm64/include/asm/kvm_asm.h | 26 | ||||
-rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 42 | ||||
-rw-r--r-- | arch/arm64/include/uapi/asm/kvm.h | 37 | ||||
-rw-r--r-- | arch/arm64/kernel/asm-offsets.c | 9 | ||||
-rw-r--r-- | arch/arm64/kernel/hw_breakpoint.c | 12 | ||||
-rw-r--r-- | arch/arm64/kvm/Makefile | 2 | ||||
-rw-r--r-- | arch/arm64/kvm/debug.c | 217 | ||||
-rw-r--r-- | arch/arm64/kvm/guest.c | 43 | ||||
-rw-r--r-- | arch/arm64/kvm/handle_exit.c | 44 | ||||
-rw-r--r-- | arch/arm64/kvm/hyp.S | 617 | ||||
-rw-r--r-- | arch/arm64/kvm/reset.c | 20 | ||||
-rw-r--r-- | arch/arm64/kvm/sys_regs.c | 291 | ||||
-rw-r--r-- | arch/arm64/kvm/sys_regs.h | 6 | ||||
-rw-r--r-- | arch/arm64/kvm/sys_regs_generic_v8.c | 2 | ||||
-rw-r--r-- | arch/arm64/kvm/trace.h | 123 |
17 files changed, 1045 insertions, 465 deletions
diff --git a/arch/arm64/include/asm/hw_breakpoint.h b/arch/arm64/include/asm/hw_breakpoint.h index 52b484b6aa1a..4c47cb2fbb52 100644 --- a/arch/arm64/include/asm/hw_breakpoint.h +++ b/arch/arm64/include/asm/hw_breakpoint.h @@ -16,6 +16,8 @@ #ifndef __ASM_HW_BREAKPOINT_H #define __ASM_HW_BREAKPOINT_H +#include <asm/cputype.h> + #ifdef __KERNEL__ struct arch_hw_breakpoint_ctrl { @@ -132,5 +134,17 @@ static inline void ptrace_hw_copy_thread(struct task_struct *task) extern struct pmu perf_ops_bp; +/* Determine number of BRP registers available. */ +static inline int get_num_brps(void) +{ + return ((read_cpuid(ID_AA64DFR0_EL1) >> 12) & 0xf) + 1; +} + +/* Determine number of WRP registers available. */ +static inline int get_num_wrps(void) +{ + return ((read_cpuid(ID_AA64DFR0_EL1) >> 20) & 0xf) + 1; +} + #endif /* __KERNEL__ */ #endif /* __ASM_BREAKPOINT_H */ diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index ac6fafb95fe7..7605e095217f 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -171,10 +171,13 @@ #define HSTR_EL2_TTEE (1 << 16) #define HSTR_EL2_T(x) (1 << x) +/* Hyp Coproccessor Trap Register Shifts */ +#define CPTR_EL2_TFP_SHIFT 10 + /* Hyp Coprocessor Trap Register */ #define CPTR_EL2_TCPAC (1 << 31) #define CPTR_EL2_TTA (1 << 20) -#define CPTR_EL2_TFP (1 << 10) +#define CPTR_EL2_TFP (1 << CPTR_EL2_TFP_SHIFT) /* Hyp Debug Configuration Register bits */ #define MDCR_EL2_TDRA (1 << 11) diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index 3c5fe685a2d6..67fa0de3d483 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -46,24 +46,16 @@ #define CNTKCTL_EL1 20 /* Timer Control Register (EL1) */ #define PAR_EL1 21 /* Physical Address Register */ #define MDSCR_EL1 22 /* Monitor Debug System Control Register */ -#define DBGBCR0_EL1 23 /* Debug Breakpoint Control Registers (0-15) */ -#define DBGBCR15_EL1 38 -#define DBGBVR0_EL1 39 /* Debug Breakpoint Value Registers (0-15) */ -#define DBGBVR15_EL1 54 -#define DBGWCR0_EL1 55 /* Debug Watchpoint Control Registers (0-15) */ -#define DBGWCR15_EL1 70 -#define DBGWVR0_EL1 71 /* Debug Watchpoint Value Registers (0-15) */ -#define DBGWVR15_EL1 86 -#define MDCCINT_EL1 87 /* Monitor Debug Comms Channel Interrupt Enable Reg */ +#define MDCCINT_EL1 23 /* Monitor Debug Comms Channel Interrupt Enable Reg */ /* 32bit specific registers. Keep them at the end of the range */ -#define DACR32_EL2 88 /* Domain Access Control Register */ -#define IFSR32_EL2 89 /* Instruction Fault Status Register */ -#define FPEXC32_EL2 90 /* Floating-Point Exception Control Register */ -#define DBGVCR32_EL2 91 /* Debug Vector Catch Register */ -#define TEECR32_EL1 92 /* ThumbEE Configuration Register */ -#define TEEHBR32_EL1 93 /* ThumbEE Handler Base Register */ -#define NR_SYS_REGS 94 +#define DACR32_EL2 24 /* Domain Access Control Register */ +#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 /* 32bit mapping */ #define c0_MPIDR (MPIDR_EL1 * 2) /* MultiProcessor ID Register */ @@ -132,6 +124,8 @@ 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..415938dc45cf 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -103,15 +103,34 @@ struct kvm_vcpu_arch { /* HYP configuration */ u64 hcr_el2; + u32 mdcr_el2; /* Exception Information */ struct kvm_vcpu_fault_info fault; - /* Debug state */ + /* Guest debug state */ u64 debug_flags; + /* + * We maintain more than a single set of debug registers to support + * debugging the guest from the host and to maintain separate host and + * guest state during world switches. vcpu_debug_state are the debug + * registers of the vcpu as the guest sees them. host_debug_state are + * the host registers which are saved and restored during + * world switches. external_debug_state contains the debug + * values we want to debug the guest. This is set via the + * KVM_SET_GUEST_DEBUG ioctl. + * + * debug_ptr points to the set of debug registers that should be loaded + * onto the hardware when running the guest. + */ + struct kvm_guest_debug_arch *debug_ptr; + struct kvm_guest_debug_arch vcpu_debug_state; + struct kvm_guest_debug_arch external_debug_state; + /* Pointer to host CPU context */ kvm_cpu_context_t *host_cpu_context; + struct kvm_guest_debug_arch host_debug_state; /* VGIC state */ struct vgic_cpu vgic_cpu; @@ -122,6 +141,17 @@ struct kvm_vcpu_arch { * here. */ + /* + * Guest registers we preserve during guest debugging. + * + * These shadow registers are updated by the kvm_handle_sys_reg + * trap handler if the guest accesses or updates them while we + * are using guest debug. + */ + struct { + u32 mdscr_el1; + } guest_debug_preserved; + /* Don't run the guest */ bool pause; @@ -216,15 +246,15 @@ static inline void __cpu_init_hyp_mode(phys_addr_t boot_pgd_ptr, hyp_stack_ptr, vector_ptr); } -struct vgic_sr_vectors { - void *save_vgic; - void *restore_vgic; -}; - static inline void kvm_arch_hardware_disable(void) {} static inline void kvm_arch_hardware_unsetup(void) {} 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); +void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu); + #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index d26832022127..0cd7b5947dfc 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -53,14 +53,20 @@ struct kvm_regs { struct user_fpsimd_state fp_regs; }; -/* Supported Processor Types */ +/* + * Supported CPU Targets - Adding a new target type is not recommended, + * unless there are some special registers not supported by the + * genericv8 syreg table. + */ #define KVM_ARM_TARGET_AEM_V8 0 #define KVM_ARM_TARGET_FOUNDATION_V8 1 #define KVM_ARM_TARGET_CORTEX_A57 2 #define KVM_ARM_TARGET_XGENE_POTENZA 3 #define KVM_ARM_TARGET_CORTEX_A53 4 +/* Generic ARM v8 target */ +#define KVM_ARM_TARGET_GENERIC_V8 5 -#define KVM_ARM_NUM_TARGETS 5 +#define KVM_ARM_NUM_TARGETS 6 /* KVM_ARM_SET_DEVICE_ADDR ioctl id encoding */ #define KVM_ARM_DEVICE_TYPE_SHIFT 0 @@ -100,12 +106,39 @@ struct kvm_sregs { struct kvm_fpu { }; +/* + * See v8 ARM ARM D7.3: Debug Registers + * + * The architectural limit is 16 debug registers of each type although + * in practice there are usually less (see ID_AA64DFR0_EL1). + * + * Although the control registers are architecturally defined as 32 + * bits wide we use a 64 bit structure here to keep parity with + * KVM_GET/SET_ONE_REG behaviour which treats all system registers as + * 64 bit values. It also allows for the possibility of the + * architecture expanding the control registers without having to + * change the userspace ABI. + */ +#define KVM_ARM_MAX_DBG_REGS 16 struct kvm_guest_debug_arch { + __u64 dbg_bcr[KVM_ARM_MAX_DBG_REGS]; + __u64 dbg_bvr[KVM_ARM_MAX_DBG_REGS]; + __u64 dbg_wcr[KVM_ARM_MAX_DBG_REGS]; + __u64 dbg_wvr[KVM_ARM_MAX_DBG_REGS]; }; struct kvm_debug_exit_arch { + __u32 hsr; + __u64 far; /* used for watchpoints */ }; +/* + * Architecture specific defines for kvm_guest_debug->control + */ + +#define KVM_GUESTDBG_USE_SW_BP (1 << 16) +#define KVM_GUESTDBG_USE_HW (1 << 17) + struct kvm_sync_regs { }; diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index c99701a34d7b..8d89cf8dae55 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -116,17 +116,22 @@ int main(void) DEFINE(VCPU_FAR_EL2, offsetof(struct kvm_vcpu, arch.fault.far_el2)); 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_DEBUG_PTR, offsetof(struct kvm_vcpu, arch.debug_ptr)); + DEFINE(DEBUG_BCR, offsetof(struct kvm_guest_debug_arch, dbg_bcr)); + DEFINE(DEBUG_BVR, offsetof(struct kvm_guest_debug_arch, dbg_bvr)); + DEFINE(DEBUG_WCR, offsetof(struct kvm_guest_debug_arch, dbg_wcr)); + DEFINE(DEBUG_WVR, offsetof(struct kvm_guest_debug_arch, dbg_wvr)); 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_HOST_DEBUG_STATE, offsetof(struct kvm_vcpu, arch.host_debug_state)); DEFINE(VCPU_TIMER_CNTV_CTL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_ctl)); DEFINE(VCPU_TIMER_CNTV_CVAL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_cval)); DEFINE(KVM_TIMER_CNTVOFF, offsetof(struct kvm, arch.timer.cntvoff)); 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_SAVE_FN, offsetof(struct vgic_sr_vectors, save_vgic)); - DEFINE(VGIC_RESTORE_FN, offsetof(struct vgic_sr_vectors, restore_vgic)); 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)); diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c index 003bc3d50636..c97040ecf838 100644 --- a/arch/arm64/kernel/hw_breakpoint.c +++ b/arch/arm64/kernel/hw_breakpoint.c @@ -48,18 +48,6 @@ static DEFINE_PER_CPU(int, stepping_kernel_bp); static int core_num_brps; static int core_num_wrps; -/* Determine number of BRP registers available. */ -static int get_num_brps(void) -{ - return ((read_cpuid(ID_AA64DFR0_EL1) >> 12) & 0xf) + 1; -} - -/* Determine number of WRP registers available. */ -static int get_num_wrps(void) -{ - return ((read_cpuid(ID_AA64DFR0_EL1) >> 20) & 0xf) + 1; -} - int hw_breakpoint_slots(int type) { /* 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..47e5f0feaee8 --- /dev/null +++ b/arch/arm64/kvm/debug.c @@ -0,0 +1,217 @@ +/* + * 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 <linux/hw_breakpoint.h> + +#include <asm/debug-monitors.h> +#include <asm/kvm_asm.h> +#include <asm/kvm_arm.h> +#include <asm/kvm_emulate.h> + +#include "trace.h" + +/* These are the bits of MDSCR_EL1 we may manipulate */ +#define MDSCR_EL1_DEBUG_MASK (DBG_MDSCR_SS | \ + DBG_MDSCR_KDE | \ + DBG_MDSCR_MDE) + +static DEFINE_PER_CPU(u32, mdcr_el2); + +/** + * save/restore_guest_debug_regs + * + * For some debug operations we need to tweak some guest registers. As + * a result we need to save the state of those registers before we + * make those modifications. + * + * Guest access to MDSCR_EL1 is trapped by the hypervisor and handled + * after we have restored the preserved value to the main context. + */ +static void save_guest_debug_regs(struct kvm_vcpu *vcpu) +{ + vcpu->arch.guest_debug_preserved.mdscr_el1 = vcpu_sys_reg(vcpu, MDSCR_EL1); + + trace_kvm_arm_set_dreg32("Saved MDSCR_EL1", + vcpu->arch.guest_debug_preserved.mdscr_el1); +} + +static void restore_guest_debug_regs(struct kvm_vcpu *vcpu) +{ + vcpu_sys_reg(vcpu, MDSCR_EL1) = vcpu->arch.guest_debug_preserved.mdscr_el1; + + trace_kvm_arm_set_dreg32("Restored MDSCR_EL1", + vcpu_sys_reg(vcpu, MDSCR_EL1)); +} + +/** + * 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_reset_debug_ptr - reset the debug ptr to point to the vcpu state + */ + +void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) +{ + vcpu->arch.debug_ptr = &vcpu->arch.vcpu_debug_state; +} + +/** + * 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); + + trace_kvm_arm_setup_debug(vcpu, vcpu->guest_debug); + + 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); + + /* Is Guest debugging in effect? */ + if (vcpu->guest_debug) { + /* Route all software debug exceptions to EL2 */ + vcpu->arch.mdcr_el2 |= MDCR_EL2_TDE; + + /* Save guest debug state */ + save_guest_debug_regs(vcpu); + + /* + * Single Step (ARM ARM D2.12.3 The software step state + * machine) + * + * If we are doing Single Step we need to manipulate + * the guest's MDSCR_EL1.SS and PSTATE.SS. Once the + * step has occurred the hypervisor will trap the + * debug exception and we return to userspace. + * + * If the guest attempts to single step its userspace + * we would have to deal with a trapped exception + * while in the guest kernel. Because this would be + * hard to unwind we suppress the guest's ability to + * do so by masking MDSCR_EL.SS. + * + * This confuses guest debuggers which use + * single-step behind the scenes but everything + * returns to normal once the host is no longer + * debugging the system. + */ + if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) { + *vcpu_cpsr(vcpu) |= DBG_SPSR_SS; + vcpu_sys_reg(vcpu, MDSCR_EL1) |= DBG_MDSCR_SS; + } else { + vcpu_sys_reg(vcpu, MDSCR_EL1) &= ~DBG_MDSCR_SS; + } + + trace_kvm_arm_set_dreg32("SPSR_EL2", *vcpu_cpsr(vcpu)); + + /* + * HW Breakpoints and watchpoints + * + * We simply switch the debug_ptr to point to our new + * external_debug_state which has been populated by the + * debug ioctl. The existing KVM_ARM64_DEBUG_DIRTY + * mechanism ensures the registers are updated on the + * world switch. + */ + if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) { + /* Enable breakpoints/watchpoints */ + vcpu_sys_reg(vcpu, MDSCR_EL1) |= DBG_MDSCR_MDE; + + vcpu->arch.debug_ptr = &vcpu->arch.external_debug_state; + vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY; + trap_debug = true; + + trace_kvm_arm_set_regset("BKPTS", get_num_brps(), + &vcpu->arch.debug_ptr->dbg_bcr[0], + &vcpu->arch.debug_ptr->dbg_bvr[0]); + + trace_kvm_arm_set_regset("WAPTS", get_num_wrps(), + &vcpu->arch.debug_ptr->dbg_wcr[0], + &vcpu->arch.debug_ptr->dbg_wvr[0]); + } + } + + BUG_ON(!vcpu->guest_debug && + vcpu->arch.debug_ptr != &vcpu->arch.vcpu_debug_state); + + /* Trap debug register access */ + if (trap_debug) + vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA; + + trace_kvm_arm_set_dreg32("MDCR_EL2", vcpu->arch.mdcr_el2); + trace_kvm_arm_set_dreg32("MDSCR_EL1", vcpu_sys_reg(vcpu, MDSCR_EL1)); +} + +void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) +{ + trace_kvm_arm_clear_debug(vcpu->guest_debug); + + if (vcpu->guest_debug) { + restore_guest_debug_regs(vcpu); + + /* + * If we were using HW debug we need to restore the + * debug_ptr to the guest debug state. + */ + if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) { + kvm_arm_reset_debug_ptr(vcpu); + + trace_kvm_arm_set_regset("BKPTS", get_num_brps(), + &vcpu->arch.debug_ptr->dbg_bcr[0], + &vcpu->arch.debug_ptr->dbg_bvr[0]); + + trace_kvm_arm_set_regset("WAPTS", get_num_wrps(), + &vcpu->arch.debug_ptr->dbg_wcr[0], + &vcpu->arch.debug_ptr->dbg_wvr[0]); + } + } +} diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 9535bd555d1d..d250160d32bc 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -32,6 +32,8 @@ #include <asm/kvm_emulate.h> #include <asm/kvm_coproc.h> +#include "trace.h" + struct kvm_stats_debugfs_item debugfs_entries[] = { { NULL } }; @@ -293,7 +295,8 @@ int __attribute_const__ kvm_target_cpu(void) break; }; - return -EINVAL; + /* Return a default generic target */ + return KVM_ARM_TARGET_GENERIC_V8; } int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init) @@ -331,3 +334,41 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, { return -EINVAL; } + +#define KVM_GUESTDBG_VALID_MASK (KVM_GUESTDBG_ENABLE | \ + KVM_GUESTDBG_USE_SW_BP | \ + KVM_GUESTDBG_USE_HW | \ + KVM_GUESTDBG_SINGLESTEP) + +/** + * kvm_arch_vcpu_ioctl_set_guest_debug - set up guest debugging + * @kvm: pointer to the KVM struct + * @kvm_guest_debug: the ioctl data buffer + * + * This sets up and enables the VM for guest debugging. Userspace + * passes in a control flag to enable different debug types and + * potentially other architecture specific information in the rest of + * the structure. + */ +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, + struct kvm_guest_debug *dbg) +{ + trace_kvm_set_guest_debug(vcpu, dbg->control); + + if (dbg->control & ~KVM_GUESTDBG_VALID_MASK) + return -EINVAL; + + if (dbg->control & KVM_GUESTDBG_ENABLE) { + vcpu->guest_debug = dbg->control; + + /* Hardware assisted Break and Watch points */ + if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) { + vcpu->arch.external_debug_state = dbg->arch; + } + + } else { + /* If not enabled clear all flags */ + vcpu->guest_debug = 0; + } + return 0; +} diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 524fa25671fc..68a0759b1375 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -82,6 +82,45 @@ static int kvm_handle_wfx(struct kvm_vcpu *vcpu, struct kvm_run *run) return 1; } +/** + * kvm_handle_guest_debug - handle a debug exception instruction + * + * @vcpu: the vcpu pointer + * @run: access to the kvm_run structure for results + * + * We route all debug exceptions through the same handler. If both the + * guest and host are using the same debug facilities it will be up to + * userspace to re-inject the correct exception for guest delivery. + * + * @return: 0 (while setting run->exit_reason), -1 for error + */ +static int kvm_handle_guest_debug(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + u32 hsr = kvm_vcpu_get_hsr(vcpu); + int ret = 0; + + run->exit_reason = KVM_EXIT_DEBUG; + run->debug.arch.hsr = hsr; + + switch (hsr >> ESR_ELx_EC_SHIFT) { + case ESR_ELx_EC_WATCHPT_LOW: + run->debug.arch.far = vcpu->arch.fault.far_el2; + /* fall through */ + case ESR_ELx_EC_SOFTSTP_LOW: + case ESR_ELx_EC_BREAKPT_LOW: + case ESR_ELx_EC_BKPT32: + case ESR_ELx_EC_BRK64: + break; + default: + kvm_err("%s: un-handled case hsr: %#08x\n", + __func__, (unsigned int) hsr); + ret = -1; + break; + } + + return ret; +} + static exit_handle_fn arm_exit_handlers[] = { [ESR_ELx_EC_WFx] = kvm_handle_wfx, [ESR_ELx_EC_CP15_32] = kvm_handle_cp15_32, @@ -96,6 +135,11 @@ static exit_handle_fn arm_exit_handlers[] = { [ESR_ELx_EC_SYS64] = kvm_handle_sys_reg, [ESR_ELx_EC_IABT_LOW] = kvm_handle_guest_abort, [ESR_ELx_EC_DABT_LOW] = kvm_handle_guest_abort, + [ESR_ELx_EC_SOFTSTP_LOW]= kvm_handle_guest_debug, + [ESR_ELx_EC_WATCHPT_LOW]= kvm_handle_guest_debug, + [ESR_ELx_EC_BREAKPT_LOW]= kvm_handle_guest_debug, + [ESR_ELx_EC_BKPT32] = kvm_handle_guest_debug, + [ESR_ELx_EC_BRK64] = kvm_handle_guest_debug, }; static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu) diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S index 10915aaf0b01..37c89ea2c572 100644 --- a/arch/arm64/kvm/hyp.S +++ b/arch/arm64/kvm/hyp.S @@ -230,199 +230,52 @@ stp x24, x25, [x3, #160] .endm -.macro save_debug - // x2: base address for cpu context - // x3: tmp register - - mrs x26, id_aa64dfr0_el1 - ubfx x24, x26, #12, #4 // Extract BRPs - ubfx x25, x26, #20, #4 // Extract WRPs - mov w26, #15 - sub w24, w26, w24 // How many BPs to skip - sub w25, w26, w25 // How many WPs to skip - - add x3, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) - - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 -1: - mrs x20, dbgbcr15_el1 - mrs x19, dbgbcr14_el1 - mrs x18, dbgbcr13_el1 - mrs x17, dbgbcr12_el1 - mrs x16, dbgbcr11_el1 - mrs x15, dbgbcr10_el1 - mrs x14, dbgbcr9_el1 - mrs x13, dbgbcr8_el1 - mrs x12, dbgbcr7_el1 - mrs x11, dbgbcr6_el1 - mrs x10, dbgbcr5_el1 - mrs x9, dbgbcr4_el1 - mrs x8, dbgbcr3_el1 - mrs x7, dbgbcr2_el1 - mrs x6, dbgbcr1_el1 - mrs x5, dbgbcr0_el1 - - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 - -1: - str x20, [x3, #(15 * 8)] - str x19, [x3, #(14 * 8)] - str x18, [x3, #(13 * 8)] - str x17, [x3, #(12 * 8)] - str x16, [x3, #(11 * 8)] - str x15, [x3, #(10 * 8)] - str x14, [x3, #(9 * 8)] - str x13, [x3, #(8 * 8)] - str x12, [x3, #(7 * 8)] - str x11, [x3, #(6 * 8)] - str x10, [x3, #(5 * 8)] - str x9, [x3, #(4 * 8)] - str x8, [x3, #(3 * 8)] - str x7, [x3, #(2 * 8)] - str x6, [x3, #(1 * 8)] - str x5, [x3, #(0 * 8)] - - add x3, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) - - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 +.macro save_debug type + // x4: pointer to register set + // x5: number of registers to skip + // x6..x22 trashed + + adr x22, 1f + add x22, x22, x5, lsl #2 + br x22 1: - mrs x20, dbgbvr15_el1 - mrs x19, dbgbvr14_el1 - mrs x18, dbgbvr13_el1 - mrs x17, dbgbvr12_el1 - mrs x16, dbgbvr11_el1 - mrs x15, dbgbvr10_el1 - mrs x14, dbgbvr9_el1 - mrs x13, dbgbvr8_el1 - mrs x12, dbgbvr7_el1 - mrs x11, dbgbvr6_el1 - mrs x10, dbgbvr5_el1 - mrs x9, dbgbvr4_el1 - mrs x8, dbgbvr3_el1 - mrs x7, dbgbvr2_el1 - mrs x6, dbgbvr1_el1 - mrs x5, dbgbvr0_el1 - - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 - -1: - str x20, [x3, #(15 * 8)] - str x19, [x3, #(14 * 8)] - str x18, [x3, #(13 * 8)] - str x17, [x3, #(12 * 8)] - str x16, [x3, #(11 * 8)] - str x15, [x3, #(10 * 8)] - str x14, [x3, #(9 * 8)] - str x13, [x3, #(8 * 8)] - str x12, [x3, #(7 * 8)] - str x11, [x3, #(6 * 8)] - str x10, [x3, #(5 * 8)] - str x9, [x3, #(4 * 8)] - str x8, [x3, #(3 * 8)] - str x7, [x3, #(2 * 8)] - str x6, [x3, #(1 * 8)] - str x5, [x3, #(0 * 8)] - - add x3, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 -1: - mrs x20, dbgwcr15_el1 - mrs x19, dbgwcr14_el1 - mrs x18, dbgwcr13_el1 - mrs x17, dbgwcr12_el1 - mrs x16, dbgwcr11_el1 - mrs x15, dbgwcr10_el1 - mrs x14, dbgwcr9_el1 - mrs x13, dbgwcr8_el1 - mrs x12, dbgwcr7_el1 - mrs x11, dbgwcr6_el1 - mrs x10, dbgwcr5_el1 - mrs x9, dbgwcr4_el1 - mrs x8, dbgwcr3_el1 - mrs x7, dbgwcr2_el1 - mrs x6, dbgwcr1_el1 - mrs x5, dbgwcr0_el1 - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 - -1: - str x20, [x3, #(15 * 8)] - str x19, [x3, #(14 * 8)] - str x18, [x3, #(13 * 8)] - str x17, [x3, #(12 * 8)] - str x16, [x3, #(11 * 8)] - str x15, [x3, #(10 * 8)] - str x14, [x3, #(9 * 8)] - str x13, [x3, #(8 * 8)] - str x12, [x3, #(7 * 8)] - str x11, [x3, #(6 * 8)] - str x10, [x3, #(5 * 8)] - str x9, [x3, #(4 * 8)] - str x8, [x3, #(3 * 8)] - str x7, [x3, #(2 * 8)] - str x6, [x3, #(1 * 8)] - str x5, [x3, #(0 * 8)] - - add x3, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 -1: - mrs x20, dbgwvr15_el1 - mrs x19, dbgwvr14_el1 - mrs x18, dbgwvr13_el1 - mrs x17, dbgwvr12_el1 - mrs x16, dbgwvr11_el1 - mrs x15, dbgwvr10_el1 - mrs x14, dbgwvr9_el1 - mrs x13, dbgwvr8_el1 - mrs x12, dbgwvr7_el1 - mrs x11, dbgwvr6_el1 - mrs x10, dbgwvr5_el1 - mrs x9, dbgwvr4_el1 - mrs x8, dbgwvr3_el1 - mrs x7, dbgwvr2_el1 - mrs x6, dbgwvr1_el1 - mrs x5, dbgwvr0_el1 - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 - + mrs x21, \type\()15_el1 + mrs x20, \type\()14_el1 + mrs x19, \type\()13_el1 + mrs x18, \type\()12_el1 + mrs x17, \type\()11_el1 + mrs x16, \type\()10_el1 + mrs x15, \type\()9_el1 + mrs x14, \type\()8_el1 + mrs x13, \type\()7_el1 + mrs x12, \type\()6_el1 + mrs x11, \type\()5_el1 + mrs x10, \type\()4_el1 + mrs x9, \type\()3_el1 + mrs x8, \type\()2_el1 + mrs x7, \type\()1_el1 + mrs x6, \type\()0_el1 + + adr x22, 1f + add x22, x22, x5, lsl #2 + br x22 1: - str x20, [x3, #(15 * 8)] - str x19, [x3, #(14 * 8)] - str x18, [x3, #(13 * 8)] - str x17, [x3, #(12 * 8)] - str x16, [x3, #(11 * 8)] - str x15, [x3, #(10 * 8)] - str x14, [x3, #(9 * 8)] - str x13, [x3, #(8 * 8)] - str x12, [x3, #(7 * 8)] - str x11, [x3, #(6 * 8)] - str x10, [x3, #(5 * 8)] - str x9, [x3, #(4 * 8)] - str x8, [x3, #(3 * 8)] - str x7, [x3, #(2 * 8)] - str x6, [x3, #(1 * 8)] - str x5, [x3, #(0 * 8)] - - mrs x21, mdccint_el1 - str x21, [x2, #CPU_SYSREG_OFFSET(MDCCINT_EL1)] + str x21, [x4, #(15 * 8)] + str x20, [x4, #(14 * 8)] + str x19, [x4, #(13 * 8)] + str x18, [x4, #(12 * 8)] + str x17, [x4, #(11 * 8)] + str x16, [x4, #(10 * 8)] + str x15, [x4, #(9 * 8)] + str x14, [x4, #(8 * 8)] + str x13, [x4, #(7 * 8)] + str x12, [x4, #(6 * 8)] + str x11, [x4, #(5 * 8)] + str x10, [x4, #(4 * 8)] + str x9, [x4, #(3 * 8)] + str x8, [x4, #(2 * 8)] + str x7, [x4, #(1 * 8)] + str x6, [x4, #(0 * 8)] .endm .macro restore_sysregs @@ -467,195 +320,52 @@ msr mdscr_el1, x25 .endm -.macro restore_debug - // x2: base address for cpu context - // x3: tmp register - - mrs x26, id_aa64dfr0_el1 - ubfx x24, x26, #12, #4 // Extract BRPs - ubfx x25, x26, #20, #4 // Extract WRPs - mov w26, #15 - sub w24, w26, w24 // How many BPs to skip - sub w25, w26, w25 // How many WPs to skip - - add x3, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) +.macro restore_debug type + // x4: pointer to register set + // x5: number of registers to skip + // x6..x22 trashed - adr x2 |