diff options
Diffstat (limited to 'target/arm/kvm64.c')
-rw-r--r-- | target/arm/kvm64.c | 982 |
1 files changed, 982 insertions, 0 deletions
diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c new file mode 100644 index 0000000000..61111091ad --- /dev/null +++ b/target/arm/kvm64.c @@ -0,0 +1,982 @@ +/* + * 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/ptrace.h> + +#include <linux/elf.h> +#include <linux/kvm.h> + +#include "qemu-common.h" +#include "cpu.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 "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 bool kvm_arm_pmu_support_ctrl(CPUState *cs, struct kvm_device_attr *attr) +{ + return kvm_vcpu_ioctl(cs, KVM_HAS_DEVICE_ATTR, attr) == 0; +} + +int kvm_arm_pmu_create(CPUState *cs, int irq) +{ + int err; + + struct kvm_device_attr attr = { + .group = KVM_ARM_VCPU_PMU_V3_CTRL, + .addr = (intptr_t)&irq, + .attr = KVM_ARM_VCPU_PMU_V3_IRQ, + .flags = 0, + }; + + if (!kvm_arm_pmu_support_ctrl(cs, &attr)) { + return 0; + } + + err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr); + if (err < 0) { + fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n", + strerror(-err)); + abort(); + } + + attr.group = KVM_ARM_VCPU_PMU_V3_CTRL; + attr.attr = KVM_ARM_VCPU_PMU_V3_INIT; + attr.addr = 0; + attr.flags = 0; + + err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr); + if (err < 0) { + fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n", + strerror(-err)); + abort(); + } + + return 1; +} + +static inline void set_feature(uint64_t *features, int feature) +{ + *features |= 1ULL << feature; +} + +static inline void unset_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); + set_feature(&features, ARM_FEATURE_PMU); + + 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); + CPUARMState *env = &cpu->env; + + 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; + } + if (!kvm_irqchip_in_kernel() || + !kvm_check_extension(cs->kvm_state, KVM_CAP_ARM_PMU_V3)) { + cpu->has_pmu = false; + } + if (cpu->has_pmu) { + cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_PMU_V3; + } else { + unset_feature(&env->features, ARM_FEATURE_PMU); + } + + /* 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; +} |