/* * ARM implementation of KVM hooks, 64 bit specific code * * Copyright Mian-M. Hamayun 2013, Virtual Open Systems * Copyright Alex BennĂ©e 2014, Linaro * * This work is licensed under the terms of the GNU GPL, version 2 or later. * See the COPYING file in the top-level directory. * */ #include "qemu/osdep.h" #include <sys/ioctl.h> #include <sys/mman.h> #include <sys/ptrace.h> #include <linux/elf.h> #include <linux/kvm.h> #include "qemu-common.h" #include "qemu/timer.h" #include "qemu/error-report.h" #include "qemu/host-utils.h" #include "exec/gdbstub.h" #include "sysemu/sysemu.h" #include "sysemu/kvm.h" #include "kvm_arm.h" #include "cpu.h" #include "internals.h" #include "hw/arm/arm.h" static bool have_guest_debug; /* * Although the ARM implementation of hardware assisted debugging * allows for different breakpoints per-core, the current GDB * interface treats them as a global pool of registers (which seems to * be the case for x86, ppc and s390). As a result we store one copy * of registers which is used for all active cores. * * Write access is serialised by virtue of the GDB protocol which * updates things. Read access (i.e. when the values are copied to the * vCPU) is also gated by GDB's run control. * * This is not unreasonable as most of the time debugging kernels you * never know which core will eventually execute your function. */ typedef struct { uint64_t bcr; uint64_t bvr; } HWBreakpoint; /* The watchpoint registers can cover more area than the requested * watchpoint so we need to store the additional information * somewhere. We also need to supply a CPUWatchpoint to the GDB stub * when the watchpoint is hit. */ typedef struct { uint64_t wcr; uint64_t wvr; CPUWatchpoint details; } HWWatchpoint; /* Maximum and current break/watch point counts */ int max_hw_bps, max_hw_wps; GArray *hw_breakpoints, *hw_watchpoints; #define cur_hw_wps (hw_watchpoints->len) #define cur_hw_bps (hw_breakpoints->len) #define get_hw_bp(i) (&g_array_index(hw_breakpoints, HWBreakpoint, i)) #define get_hw_wp(i) (&g_array_index(hw_watchpoints, HWWatchpoint, i)) /** * kvm_arm_init_debug() - check for guest debug capabilities * @cs: CPUState * * kvm_check_extension returns the number of debug registers we have * or 0 if we have none. * */ static void kvm_arm_init_debug(CPUState *cs) { have_guest_debug = kvm_check_extension(cs->kvm_state, KVM_CAP_SET_GUEST_DEBUG); max_hw_wps = kvm_check_extension(cs->kvm_state, KVM_CAP_GUEST_DEBUG_HW_WPS); hw_watchpoints = g_array_sized_new(true, true, sizeof(HWWatchpoint), max_hw_wps); max_hw_bps = kvm_check_extension(cs->kvm_state, KVM_CAP_GUEST_DEBUG_HW_BPS); hw_breakpoints = g_array_sized_new(true, true, sizeof(HWBreakpoint), max_hw_bps); return; } /** * insert_hw_breakpoint() * @addr: address of breakpoint * * See ARM ARM D2.9.1 for details but here we are only going to create * simple un-linked breakpoints (i.e. we don't chain breakpoints * together to match address and context or vmid). The hardware is * capable of fancier matching but that will require exposing that * fanciness to GDB's interface * * D7.3.2 DBGBCR<n>_EL1, Debug Breakpoint Control Registers * * 31 24 23 20 19 16 15 14 13 12 9 8 5 4 3 2 1 0 * +------+------+-------+-----+----+------+-----+------+-----+---+ * | RES0 | BT | LBN | SSC | HMC| RES0 | BAS | RES0 | PMC | E | * +------+------+-------+-----+----+------+-----+------+-----+---+ * * BT: Breakpoint type (0 = unlinked address match) * LBN: Linked BP number (0 = unused) * SSC/HMC/PMC: Security, Higher and Priv access control (Table D-12) * BAS: Byte Address Select (RES1 for AArch64) * E: Enable bit */ static int insert_hw_breakpoint(target_ulong addr) { HWBreakpoint brk = { .bcr = 0x1, /* BCR E=1, enable */ .bvr = addr }; if (cur_hw_bps >= max_hw_bps) { return -ENOBUFS; } brk.bcr = deposit32(brk.bcr, 1, 2, 0x3); /* PMC = 11 */ brk.bcr = deposit32(brk.bcr, 5, 4, 0xf); /* BAS = RES1 */ g_array_append_val(hw_breakpoints, brk); return 0; } /** * delete_hw_breakpoint() * @pc: address of breakpoint * * Delete a breakpoint and shuffle any above down */ static int delete_hw_breakpoint(target_ulong pc) { int i; for (i = 0; i < hw_breakpoints->len; i++) { HWBreakpoint *brk = get_hw_bp(i); if (brk->bvr == pc) { g_array_remove_index(hw_breakpoints, i); return 0; } } return -ENOENT; } /** * insert_hw_watchpoint() * @addr: address of watch point * @len: size of area * @type: type of watch point * * See ARM ARM D2.10. As with the breakpoints we can do some advanced * stuff if we want to. The watch points can be linked with the break * points above to make them context aware. However for simplicity * currently we only deal with simple read/write watch points. * * D7.3.11 DBGWCR<n>_EL1, Debug Watchpoint Control Registers * * 31 29 28 24 23 21 20 19 16 15 14 13 12 5 4 3 2 1 0 * +------+-------+------+----+-----+-----+-----+-----+-----+-----+---+ * | RES0 | MASK | RES0 | WT | LBN | SSC | HMC | BAS | LSC | PAC | E | * +------+-------+------+----+-----+-----+-----+-----+-----+-----+---+ * * MASK: num bits addr mask (0=none,01/10=res,11=3 bits (8 bytes)) * WT: 0 - unlinked, 1 - linked (not currently used) * LBN: Linked BP number (not currently used) * SSC/HMC/PAC: Security, Higher and Priv access control (Table D2-11) * BAS: Byte Address Select * LSC: Load/Store control (01: load, 10: store, 11: both) * E: Enable * * The bottom 2 bits of the value register are masked. Therefore to * break on any sizes smaller than an unaligned word you need to set * MASK=0, BAS=bit per byte in question. For larger regions (^2) you * need to ensure you mask the address as required and set BAS=0xff */ static int insert_hw_watchpoint(target_ulong addr, target_ulong len, int type) { HWWatchpoint wp = { .wcr = 1, /* E=1, enable */ .wvr = addr & (~0x7ULL), .details = { .vaddr = addr, .len = len } }; if (cur_hw_wps >= max_hw_wps) { return -ENOBUFS; } /* * HMC=0 SSC=0 PAC=3 will hit EL0 or EL1, any security state, * valid whether EL3 is implemented or not */ wp.wcr = deposit32(wp.wcr, 1, 2, 3); switch (type) { case GDB_WATCHPOINT_READ: wp.wcr = deposit32(wp.wcr, 3, 2, 1); wp.details.flags = BP_MEM_READ; break; case GDB_WATCHPOINT_WRITE: wp.wcr = deposit32(wp.wcr, 3, 2, 2); wp.details.flags = BP_MEM_WRITE; break; case GDB_WATCHPOINT_ACCESS: wp.wcr = deposit32(wp.wcr, 3, 2, 3); wp.details.flags = BP_MEM_ACCESS; break; default: g_assert_not_reached(); break; } if (len <= 8) { /* we align the address and set the bits in BAS */ int off = addr & 0x7; int bas = (1 << len) - 1; wp.wcr = deposit32(wp.wcr, 5 + off, 8 - off, bas); } else { /* For ranges above 8 bytes we need to be a power of 2 */ if (is_power_of_2(len)) { int bits = ctz64(len); wp.wvr &= ~((1 << bits) - 1); wp.wcr = deposit32(wp.wcr, 24, 4, bits); wp.wcr = deposit32(wp.wcr, 5, 8, 0xff); } else { return -ENOBUFS; } } g_array_append_val(hw_watchpoints, wp); return 0; } static bool check_watchpoint_in_range(int i, target_ulong addr) { HWWatchpoint *wp = get_hw_wp(i); uint64_t addr_top, addr_bottom = wp->wvr; int bas = extract32(wp->wcr, 5, 8); int mask = extract32(wp->wcr, 24, 4); if (mask) { addr_top = addr_bottom + (1 << mask); } else { /* BAS must be contiguous but can offset against the base * address in DBGWVR */ addr_bottom = addr_bottom + ctz32(bas); addr_top = addr_bottom + clo32(bas); } if (addr >= addr_bottom && addr <= addr_top) { return true; } return false; } /** * delete_hw_watchpoint() * @addr: address of breakpoint * * Delete a breakpoint and shuffle any above down */ static int delete_hw_watchpoint(target_ulong addr, target_ulong len, int type) { int i; for (i = 0; i < cur_hw_wps; i++) { if (check_watchpoint_in_range(i, addr)) { g_array_remove_index(hw_watchpoints, i); return 0; } } return -ENOENT; } int kvm_arch_insert_hw_breakpoint(target_ulong addr, target_ulong len, int type) { switch (type) { case GDB_BREAKPOINT_HW: return insert_hw_breakpoint(addr); break; case GDB_WATCHPOINT_READ: case GDB_WATCHPOINT_WRITE: case GDB_WATCHPOINT_ACCESS: return insert_hw_watchpoint(addr, len, type); default: return -ENOSYS; } } int kvm_arch_remove_hw_breakpoint(target_ulong addr, target_ulong len, int type) { switch (type) { case GDB_BREAKPOINT_HW: return delete_hw_breakpoint(addr); break; case GDB_WATCHPOINT_READ: case GDB_WATCHPOINT_WRITE: case GDB_WATCHPOINT_ACCESS: return delete_hw_watchpoint(addr, len, type); default: return -ENOSYS; } } void kvm_arch_remove_all_hw_breakpoints(void) { if (cur_hw_wps > 0) { g_array_remove_range(hw_watchpoints, 0, cur_hw_wps); } if (cur_hw_bps > 0) { g_array_remove_range(hw_breakpoints, 0, cur_hw_bps); } } void kvm_arm_copy_hw_debug_data(struct kvm_guest_debug_arch *ptr) { int i; memset(ptr, 0, sizeof(struct kvm_guest_debug_arch)); for (i = 0; i < max_hw_wps; i++) { HWWatchpoint *wp = get_hw_wp(i); ptr->dbg_wcr[i] = wp->wcr; ptr->dbg_wvr[i] = wp->wvr; } for (i = 0; i < max_hw_bps; i++) { HWBreakpoint *bp = get_hw_bp(i); ptr->dbg_bcr[i] = bp->bcr; ptr->dbg_bvr[i] = bp->bvr; } } bool kvm_arm_hw_debug_active(CPUState *cs) { return ((cur_hw_wps > 0) || (cur_hw_bps > 0)); } static bool find_hw_breakpoint(CPUState *cpu, target_ulong pc) { int i; for (i = 0; i < cur_hw_bps; i++) { HWBreakpoint *bp = get_hw_bp(i); if (bp->bvr == pc) { return true; } } return false; } static CPUWatchpoint *find_hw_watchpoint(CPUState *cpu, target_ulong addr) { int i; for (i = 0; i < cur_hw_wps; i++) { if (check_watchpoint_in_range(i, addr)) { return &get_hw_wp(i)->details; } } return NULL; } static inline void set_feature(uint64_t *features, int feature) { *features |= 1ULL << feature; } bool kvm_arm_get_host_cpu_features(ARMHostCPUClass *ahcc) { /* Identify the feature bits corresponding to the host CPU, and * fill out the ARMHostCPUClass fields accordingly. To do this * we have to create a scratch VM, create a single CPU inside it, * and then query that CPU for the relevant ID registers. * For AArch64 we currently don't care about ID registers at * all; we just want to know the CPU type. */ int fdarray[3]; uint64_t features = 0; /* Old kernels may not know about the PREFERRED_TARGET ioctl: however * we know these will only support creating one kind of guest CPU, * which is its preferred CPU type. Fortunately these old kernels * support only a very limited number of CPUs. */ static const uint32_t cpus_to_try[] = { KVM_ARM_TARGET_AEM_V8, KVM_ARM_TARGET_FOUNDATION_V8, KVM_ARM_TARGET_CORTEX_A57, QEMU_KVM_ARM_TARGET_NONE }; struct kvm_vcpu_init init; if (!kvm_arm_create_scratch_host_vcpu(cpus_to_try, fdarray, &init)) { return false; } ahcc->target = init.target; ahcc->dtb_compatible = "arm,arm-v8"; kvm_arm_destroy_scratch_host_vcpu(fdarray); /* We can assume any KVM supporting CPU is at least a v8 * with VFPv4+Neon; this in turn implies most of the other * feature bits. */ set_feature(&features, ARM_FEATURE_V8); set_feature(&features, ARM_FEATURE_VFP4); set_feature(&features, ARM_FEATURE_NEON); set_feature(&features, ARM_FEATURE_AARCH64); ahcc->features = features; return true; } #define ARM_CPU_ID_MPIDR 3, 0, 0, 0, 5 int kvm_arch_init_vcpu(CPUState *cs) { int ret; uint64_t mpidr; ARMCPU *cpu = ARM_CPU(cs); if (cpu->kvm_target == QEMU_KVM_ARM_TARGET_NONE || !object_dynamic_cast(OBJECT(cpu), TYPE_AARCH64_CPU)) { fprintf(stderr, "KVM is not supported for this guest CPU type\n"); return -EINVAL; } /* Determine init features for this CPU */ memset(cpu->kvm_init_features, 0, sizeof(cpu->kvm_init_features)); if (cpu->start_powered_off) { cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_POWER_OFF; } if (kvm_check_extension(cs->kvm_state, KVM_CAP_ARM_PSCI_0_2)) { cpu->psci_version = 2; cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_PSCI_0_2; } if (!arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) { cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_EL1_32BIT; } /* Do KVM_ARM_VCPU_INIT ioctl */ ret = kvm_arm_vcpu_init(cs); if (ret) { return ret; } /* * When KVM is in use, PSCI is emulated in-kernel and not by qemu. * Currently KVM has its own idea about MPIDR assignment, so we * override our defaults with what we get from KVM. */ ret = kvm_get_one_reg(cs, ARM64_SYS_REG(ARM_CPU_ID_MPIDR), &mpidr); if (ret) { return ret; } cpu->mp_affinity = mpidr & ARM64_AFFINITY_MASK; kvm_arm_init_debug(cs); return kvm_arm_init_cpreg_list(cpu); } bool kvm_arm_reg_syncs_via_cpreg_list(uint64_t regidx) { /* Return true if the regidx is a register we should synchronize * via the cpreg_tuples array (ie is not a core reg we sync by * hand in kvm_arch_get/put_registers()) */ switch (regidx & KVM_REG_ARM_COPROC_MASK) { case KVM_REG_ARM_CORE: return false; default: return true; } } typedef struct CPRegStateLevel { uint64_t regidx; int level; } CPRegStateLevel; /* All system registers not listed in the following table are assumed to be * of the level KVM_PUT_RUNTIME_STATE. If a register should be written less * often, you must add it to this table with a state of either * KVM_PUT_RESET_STATE or KVM_PUT_FULL_STATE. */ static const CPRegStateLevel non_runtime_cpregs[] = { { KVM_REG_ARM_TIMER_CNT, KVM_PUT_FULL_STATE }, }; int kvm_arm_cpreg_level(uint64_t regidx) { int i; for (i = 0; i < ARRAY_SIZE(non_runtime_cpregs); i++) { const CPRegStateLevel *l = &non_runtime_cpregs[i]; if (l->regidx == regidx) { return l->level; } } return KVM_PUT_RUNTIME_STATE; } #define AARCH64_CORE_REG(x) (KVM_REG_ARM64 | KVM_REG_SIZE_U64 | \ KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(x)) #define AARCH64_SIMD_CORE_REG(x) (KVM_REG_ARM64 | KVM_REG_SIZE_U128 | \ KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(x)) #define AARCH64_SIMD_CTRL_REG(x) (KVM_REG_ARM64 | KVM_REG_SIZE_U32 | \ KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(x)) int kvm_arch_put_registers(CPUState *cs, int level) { struct kvm_one_reg reg; uint32_t fpr; uint64_t val; int i; int ret; unsigned int el; ARMCPU *cpu = ARM_CPU(cs); CPUARMState *env = &cpu->env; /* If we are in AArch32 mode then we need to copy the AArch32 regs to the * AArch64 registers before pushing them out to 64-bit KVM. */ if (!is_a64(env)) { aarch64_sync_32_to_64(env); } for (i = 0; i < 31; i++) { reg.id = AARCH64_CORE_REG(regs.regs[i]); reg.addr = (uintptr_t) &env->xregs[i]; ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, ®); if (ret) { return ret; } } /* KVM puts SP_EL0 in regs.sp and SP_EL1 in regs.sp_el1. On the * QEMU side we keep the current SP in xregs[31] as well. */ aarch64_save_sp(env, 1); reg.id = AARCH64_CORE_REG(regs.sp); reg.addr = (uintptr_t) &env->sp_el[0]; ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, ®); if (ret) { return ret; } reg.id = AARCH64_CORE_REG(sp_el1); reg.addr = (uintptr_t) &env->sp_el[1]; ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, ®); if (ret) { return ret; } /* Note that KVM thinks pstate is 64 bit but we use a uint32_t */ if (is_a64(env)) { val = pstate_read(env); } else { val = cpsr_read(env); } reg.id = AARCH64_CORE_REG(regs.pstate); reg.addr = (uintptr_t) &val; ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, ®); if (ret) { return ret; } reg.id = AARCH64_CORE_REG(regs.pc); reg.addr = (uintptr_t) &env->pc; ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, ®); if (ret) { return ret; } reg.id = AARCH64_CORE_REG(elr_el1); reg.addr = (uintptr_t) &env->elr_el[1]; ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, ®); if (ret) { return ret; } /* Saved Program State Registers * * Before we restore from the banked_spsr[] array we need to * ensure that any modifications to env->spsr are correctly * reflected in the banks. */ el = arm_current_el(env); if (el > 0 && !is_a64(env)) { i = bank_number(env->uncached_cpsr & CPSR_M); env->banked_spsr[i] = env->spsr; } /* KVM 0-4 map to QEMU banks 1-5 */ for (i = 0; i < KVM_NR_SPSR; i++) { reg.id = AARCH64_CORE_REG(spsr[i]); reg.addr = (uintptr_t) &env->banked_spsr[i + 1]; ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, ®); if (ret) { return ret; } } /* Advanced SIMD and FP registers * We map Qn = regs[2n+1]:regs[2n] */ for (i = 0; i < 32; i++) { int rd = i << 1; uint64_t fp_val[2]; #ifdef HOST_WORDS_BIGENDIAN fp_val[0] = env->vfp.regs[rd + 1]; fp_val[1] = env->vfp.regs[rd]; #else fp_val[1] = env->vfp.regs[rd + 1]; fp_val[0] = env->vfp.regs[rd]; #endif reg.id = AARCH64_SIMD_CORE_REG(fp_regs.vregs[i]); reg.addr = (uintptr_t)(&fp_val); ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, ®); if (ret) { return ret; } } reg.addr = (uintptr_t)(&fpr); fpr = vfp_get_fpsr(env); reg.id = AARCH64_SIMD_CTRL_REG(fp_regs.fpsr); ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, ®); if (ret) { return ret; } fpr = vfp_get_fpcr(env); reg.id = AARCH64_SIMD_CTRL_REG(fp_regs.fpcr); ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, ®); if (ret) { return ret; } if (!write_list_to_kvmstate(cpu, level)) { return EINVAL; } kvm_arm_sync_mpstate_to_kvm(cpu); return ret; } int kvm_arch_get_registers(CPUState *cs) { struct kvm_one_reg reg; uint64_t val; uint32_t fpr; unsigned int el; int i; int ret; ARMCPU *cpu = ARM_CPU(cs); CPUARMState *env = &cpu->env; for (i = 0; i < 31; i++) { reg.id = AARCH64_CORE_REG(regs.regs[i]); reg.addr = (uintptr_t) &env->xregs[i]; ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, ®); if (ret) { return ret; } } reg.id = AARCH64_CORE_REG(regs.sp); reg.addr = (uintptr_t) &env->sp_el[0]; ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, ®); if (ret) { return ret; } reg.id = AARCH64_CORE_REG(sp_el1); reg.addr = (uintptr_t) &env->sp_el[1]; ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, ®); if (ret) { return ret; } reg.id = AARCH64_CORE_REG(regs.pstate); reg.addr = (uintptr_t) &val; ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, ®); if (ret) { return ret; } env->aarch64 = ((val & PSTATE_nRW) == 0); if (is_a64(env)) { pstate_write(env, val); } else { cpsr_write(env, val, 0xffffffff, CPSRWriteRaw); } /* KVM puts SP_EL0 in regs.sp and SP_EL1 in regs.sp_el1. On the * QEMU side we keep the current SP in xregs[31] as well. */ aarch64_restore_sp(env, 1); reg.id = AARCH64_CORE_REG(regs.pc); reg.addr = (uintptr_t) &env->pc; ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, ®); if (ret) { return ret; } /* If we are in AArch32 mode then we need to sync the AArch32 regs with the * incoming AArch64 regs received from 64-bit KVM. * We must perform this after all of the registers have been acquired from * the kernel. */ if (!is_a64(env)) { aarch64_sync_64_to_32(env); } reg.id = AARCH64_CORE_REG(elr_el1); reg.addr = (uintptr_t) &env->elr_el[1]; ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, ®); if (ret) { return ret; } /* Fetch the SPSR registers * * KVM SPSRs 0-4 map to QEMU banks 1-5 */ for (i = 0; i < KVM_NR_SPSR; i++) { reg.id = AARCH64_CORE_REG(spsr[i]); reg.addr = (uintptr_t) &env->banked_spsr[i + 1]; ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, ®); if (ret) { return ret; } } el = arm_current_el(env); if (el > 0 && !is_a64(env)) { i = bank_number(env->uncached_cpsr & CPSR_M); env->spsr = env->banked_spsr[i]; } /* Advanced SIMD and FP registers * We map Qn = regs[2n+1]:regs[2n] */ for (i = 0; i < 32; i++) { uint64_t fp_val[2]; reg.id = AARCH64_SIMD_CORE_REG(fp_regs.vregs[i]); reg.addr = (uintptr_t)(&fp_val); ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, ®); if (ret) { return ret; } else { int rd = i << 1; #ifdef HOST_WORDS_BIGENDIAN env->vfp.regs[rd + 1] = fp_val[0]; env->vfp.regs[rd] = fp_val[1]; #else env->vfp.regs[rd + 1] = fp_val[1]; env->vfp.regs[rd] = fp_val[0]; #endif } } reg.addr = (uintptr_t)(&fpr); reg.id = AARCH64_SIMD_CTRL_REG(fp_regs.fpsr); ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, ®); if (ret) { return ret; } vfp_set_fpsr(env, fpr); reg.id = AARCH64_SIMD_CTRL_REG(fp_regs.fpcr); ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, ®); if (ret) { return ret; } vfp_set_fpcr(env, fpr); if (!write_kvmstate_to_list(cpu)) { return EINVAL; } /* Note that it's OK to have registers which aren't in CPUState, * so we can ignore a failure return here. */ write_list_to_cpustate(cpu); kvm_arm_sync_mpstate_to_qemu(cpu); /* TODO: other registers */ return ret; } /* C6.6.29 BRK instruction */ static const uint32_t brk_insn = 0xd4200000; int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) { if (have_guest_debug) { if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn, 4, 0) || cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&brk_insn, 4, 1)) { return -EINVAL; } return 0; } else { error_report("guest debug not supported on this kernel"); return -EINVAL; } } int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) { static uint32_t brk; if (have_guest_debug) { if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&brk, 4, 0) || brk != brk_insn || cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn, 4, 1)) { return -EINVAL; } return 0; } else { error_report("guest debug not supported on this kernel"); return -EINVAL; } } /* See v8 ARM ARM D7.2.27 ESR_ELx, Exception Syndrome Register * * To minimise translating between kernel and user-space the kernel * ABI just provides user-space with the full exception syndrome * register value to be decoded in QEMU. */ bool kvm_arm_handle_debug(CPUState *cs, struct kvm_debug_exit_arch *debug_exit) { int hsr_ec = debug_exit->hsr >> ARM_EL_EC_SHIFT; ARMCPU *cpu = ARM_CPU(cs); CPUClass *cc = CPU_GET_CLASS(cs); CPUARMState *env = &cpu->env; /* Ensure PC is synchronised */ kvm_cpu_synchronize_state(cs); switch (hsr_ec) { case EC_SOFTWARESTEP: if (cs->singlestep_enabled) { return true; } else { /* * The kernel should have suppressed the guest's ability to * single step at this point so something has gone wrong. */ error_report("%s: guest single-step while debugging unsupported" " (%"PRIx64", %"PRIx32")\n", __func__, env->pc, debug_exit->hsr); return false; } break; case EC_AA64_BKPT: if (kvm_find_sw_breakpoint(cs, env->pc)) { return true; } break; case EC_BREAKPOINT: if (find_hw_breakpoint(cs, env->pc)) { return true; } break; case EC_WATCHPOINT: { CPUWatchpoint *wp = find_hw_watchpoint(cs, debug_exit->far); if (wp) { cs->watchpoint_hit = wp; return true; } break; } default: error_report("%s: unhandled debug exit (%"PRIx32", %"PRIx64")\n", __func__, debug_exit->hsr, env->pc); } /* If we are not handling the debug exception it must belong to * the guest. Let's re-use the existing TCG interrupt code to set * everything up properly. */ cs->exception_index = EXCP_BKPT; env->exception.syndrome = debug_exit->hsr; env->exception.vaddress = debug_exit->far; cc->do_interrupt(cs); return false; }