Fetch standard register state from MSHV vCPUs to support debugging, migration, and other introspection features in QEMU.
Fetch standard register state from a MHSV vCPU's. A generic get_regs() function and a mapper to map the different register representations are introduced. Signed-off-by: Magnus Kulke <magnusku...@linux.microsoft.com> --- include/system/mshv.h | 1 + target/i386/mshv/mshv-cpu.c | 69 +++++++++++++++++++++++++++++++++++-- 2 files changed, 68 insertions(+), 2 deletions(-) diff --git a/include/system/mshv.h b/include/system/mshv.h index adce4153d9..65f7fa15a0 100644 --- a/include/system/mshv.h +++ b/include/system/mshv.h @@ -88,6 +88,7 @@ typedef enum MshvVmExit { void mshv_init_cpu_logic(void); int mshv_create_vcpu(int vm_fd, uint8_t vp_index, int *cpu_fd); void mshv_remove_vcpu(int vm_fd, int cpu_fd); +int mshv_get_standard_regs(CPUState *cpu); int mshv_run_vcpu(int vm_fd, CPUState *cpu, hv_message *msg, MshvVmExit *exit); int mshv_load_regs(CPUState *cpu); int mshv_store_regs(CPUState *cpu); diff --git a/target/i386/mshv/mshv-cpu.c b/target/i386/mshv/mshv-cpu.c index 4bd4e29b72..cb59d74eb4 100644 --- a/target/i386/mshv/mshv-cpu.c +++ b/target/i386/mshv/mshv-cpu.c @@ -61,6 +61,18 @@ int mshv_set_generic_regs(int cpu_fd, hv_register_assoc *assocs, size_t n_regs) return ioctl(cpu_fd, MSHV_SET_VP_REGISTERS, &input); } +static int get_generic_regs(int cpu_fd, struct hv_register_assoc *assocs, + size_t n_regs) +{ + struct mshv_vp_registers input = { + .count = n_regs, + .regs = assocs, + }; + + return ioctl(cpu_fd, MSHV_GET_VP_REGISTERS, &input); +} + + static int set_standard_regs(const CPUState *cpu) { X86CPU *x86cpu = X86_CPU(cpu); @@ -115,11 +127,64 @@ int mshv_store_regs(CPUState *cpu) return 0; } +static void populate_standard_regs(const hv_register_assoc *assocs, + CPUX86State *env) +{ + env->regs[R_EAX] = assocs[0].value.reg64; + env->regs[R_EBX] = assocs[1].value.reg64; + env->regs[R_ECX] = assocs[2].value.reg64; + env->regs[R_EDX] = assocs[3].value.reg64; + env->regs[R_ESI] = assocs[4].value.reg64; + env->regs[R_EDI] = assocs[5].value.reg64; + env->regs[R_ESP] = assocs[6].value.reg64; + env->regs[R_EBP] = assocs[7].value.reg64; + env->regs[R_R8] = assocs[8].value.reg64; + env->regs[R_R9] = assocs[9].value.reg64; + env->regs[R_R10] = assocs[10].value.reg64; + env->regs[R_R11] = assocs[11].value.reg64; + env->regs[R_R12] = assocs[12].value.reg64; + env->regs[R_R13] = assocs[13].value.reg64; + env->regs[R_R14] = assocs[14].value.reg64; + env->regs[R_R15] = assocs[15].value.reg64; + + env->eip = assocs[16].value.reg64; + env->eflags = assocs[17].value.reg64; + rflags_to_lflags(env); +} + +int mshv_get_standard_regs(CPUState *cpu) +{ + struct hv_register_assoc assocs[ARRAY_SIZE(STANDARD_REGISTER_NAMES)]; + int ret; + X86CPU *x86cpu = X86_CPU(cpu); + CPUX86State *env = &x86cpu->env; + int cpu_fd = mshv_vcpufd(cpu); + size_t n_regs = ARRAY_SIZE(STANDARD_REGISTER_NAMES); + + for (size_t i = 0; i < n_regs; i++) { + assocs[i].name = STANDARD_REGISTER_NAMES[i]; + } + ret = get_generic_regs(cpu_fd, assocs, n_regs); + if (ret < 0) { + error_report("failed to get standard registers"); + return -1; + } + + populate_standard_regs(assocs, env); + return 0; +} int mshv_load_regs(CPUState *cpu) { - error_report("unimplemented"); - abort(); + int ret; + + ret = mshv_get_standard_regs(cpu); + if (ret < 0) { + error_report("Failed to load standard registers"); + return -1; + } + + return 0; } int mshv_arch_put_registers(const CPUState *cpu) -- 2.34.1