This patch implements insert/remove software breakpoint process: Add an input parameter for kvm_arch_insert_sw_breakpoint() and kvm_arch_remove_sw_breakpoint() to pass the length information, which helps us to know whether it is a RVC instruction. For some remove cases, we do not have the length info, so we need to judge by ourselves.
For RISC-V, GDB treats single-step similarly to breakpoint: add a breakpoint at the next step address, then continue. So this also works for single-step debugging. Add some stubs which are necessary for building, and will be implemented later. Signed-off-by: Chao Du <duc...@eswincomputing.com> --- accel/kvm/kvm-all.c | 8 ++-- include/sysemu/kvm.h | 6 ++- target/arm/kvm.c | 6 ++- target/i386/kvm/kvm.c | 6 ++- target/mips/kvm.c | 6 ++- target/ppc/kvm.c | 6 ++- target/riscv/kvm/kvm-cpu.c | 79 ++++++++++++++++++++++++++++++++++++++ target/s390x/kvm/kvm.c | 6 ++- 8 files changed, 107 insertions(+), 16 deletions(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index c0be9f5eed..d27e77dbb2 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -3357,7 +3357,7 @@ int kvm_insert_breakpoint(CPUState *cpu, int type, vaddr addr, vaddr len) bp = g_new(struct kvm_sw_breakpoint, 1); bp->pc = addr; bp->use_count = 1; - err = kvm_arch_insert_sw_breakpoint(cpu, bp); + err = kvm_arch_insert_sw_breakpoint(cpu, bp, len); if (err) { g_free(bp); return err; @@ -3396,7 +3396,7 @@ int kvm_remove_breakpoint(CPUState *cpu, int type, vaddr addr, vaddr len) return 0; } - err = kvm_arch_remove_sw_breakpoint(cpu, bp); + err = kvm_arch_remove_sw_breakpoint(cpu, bp, len); if (err) { return err; } @@ -3426,10 +3426,10 @@ void kvm_remove_all_breakpoints(CPUState *cpu) CPUState *tmpcpu; QTAILQ_FOREACH_SAFE(bp, &s->kvm_sw_breakpoints, entry, next) { - if (kvm_arch_remove_sw_breakpoint(cpu, bp) != 0) { + if (kvm_arch_remove_sw_breakpoint(cpu, bp, 0) != 0) { /* Try harder to find a CPU that currently sees the breakpoint. */ CPU_FOREACH(tmpcpu) { - if (kvm_arch_remove_sw_breakpoint(tmpcpu, bp) == 0) { + if (kvm_arch_remove_sw_breakpoint(tmpcpu, bp, 0) == 0) { break; } } diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h index c31d9c7356..340e094ffb 100644 --- a/include/sysemu/kvm.h +++ b/include/sysemu/kvm.h @@ -391,9 +391,11 @@ struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *cpu, int kvm_sw_breakpoints_active(CPUState *cpu); int kvm_arch_insert_sw_breakpoint(CPUState *cpu, - struct kvm_sw_breakpoint *bp); + struct kvm_sw_breakpoint *bp, + vaddr len); int kvm_arch_remove_sw_breakpoint(CPUState *cpu, - struct kvm_sw_breakpoint *bp); + struct kvm_sw_breakpoint *bp, + vaddr len); int kvm_arch_insert_hw_breakpoint(vaddr addr, vaddr len, int type); int kvm_arch_remove_hw_breakpoint(vaddr addr, vaddr len, int type); void kvm_arch_remove_all_hw_breakpoints(void); diff --git a/target/arm/kvm.c b/target/arm/kvm.c index 7cf5cf31de..84593db544 100644 --- a/target/arm/kvm.c +++ b/target/arm/kvm.c @@ -2402,7 +2402,8 @@ void kvm_arch_on_sigbus_vcpu(CPUState *c, int code, void *addr) /* 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) +int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) { 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)) { @@ -2411,7 +2412,8 @@ int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) return 0; } -int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) +int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) { static uint32_t brk; diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index c5943605ee..6449f796d0 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -4992,7 +4992,8 @@ static int kvm_handle_tpr_access(X86CPU *cpu) return 1; } -int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) +int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) { static const uint8_t int3 = 0xcc; @@ -5003,7 +5004,8 @@ int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) return 0; } -int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) +int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) { uint8_t int3; diff --git a/target/mips/kvm.c b/target/mips/kvm.c index a631ab544f..129964cf6d 100644 --- a/target/mips/kvm.c +++ b/target/mips/kvm.c @@ -111,13 +111,15 @@ void kvm_mips_reset_vcpu(MIPSCPU *cpu) DPRINTF("%s\n", __func__); } -int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) +int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) { DPRINTF("%s\n", __func__); return 0; } -int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) +int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) { DPRINTF("%s\n", __func__); return 0; diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c index 46fccff786..9b76bdaa05 100644 --- a/target/ppc/kvm.c +++ b/target/ppc/kvm.c @@ -1378,7 +1378,8 @@ static int kvmppc_handle_dcr_write(CPUPPCState *env, return 0; } -int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) +int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) { /* Mixed endian case is not handled */ uint32_t sc = debug_inst_opcode; @@ -1392,7 +1393,8 @@ int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) return 0; } -int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) +int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) { uint32_t sc; diff --git a/target/riscv/kvm/kvm-cpu.c b/target/riscv/kvm/kvm-cpu.c index 473416649f..cba55c552d 100644 --- a/target/riscv/kvm/kvm-cpu.c +++ b/target/riscv/kvm/kvm-cpu.c @@ -1962,3 +1962,82 @@ static const TypeInfo riscv_kvm_cpu_type_infos[] = { }; DEFINE_TYPES(riscv_kvm_cpu_type_infos) + +static const uint32_t ebreak_insn = 0x00100073; +static const uint16_t c_ebreak_insn = 0x9002; + +int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) +{ + if (len != 4 && len != 2) { + return -EINVAL; + } + + uint8_t * insn = (len == 4) ? (uint8_t *)&ebreak_insn : + (uint8_t *)&c_ebreak_insn; + + if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn, len, 0) || + cpu_memory_rw_debug(cs, bp->pc, insn, len, 1)) { + return -EINVAL; + } + + return 0; +} + +int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) +{ + uint8_t length; + + if (len == 4 || len == 2) { + length = (uint8_t)len; + } else if (len == 0) { + /* Need to decide the instruction length in this case. */ + uint32_t read_4_bytes; + uint16_t read_2_bytes; + + if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&read_4_bytes, 4, 0) || + cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&read_2_bytes, 2, 0)) { + return -EINVAL; + } + + if (read_4_bytes == ebreak_insn) { + length = 4; + } else if (read_2_bytes == c_ebreak_insn) { + length = 2; + } else { + return -EINVAL; + } + } else { + return -EINVAL; + } + + if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn, + length, 1)) { + return -EINVAL; + } + + return 0; +} + +int kvm_arch_insert_hw_breakpoint(vaddr addr, vaddr len, int type) +{ + /* TODO; To be implemented later. */ + return -EINVAL; +} + +int kvm_arch_remove_hw_breakpoint(vaddr addr, vaddr len, int type) +{ + /* TODO; To be implemented later. */ + return -EINVAL; +} + +void kvm_arch_remove_all_hw_breakpoints(void) +{ + /* TODO; To be implemented later. */ +} + +void kvm_arch_update_guest_debug(CPUState *cs, struct kvm_guest_debug *dbg) +{ + /* TODO; To be implemented later. */ +} diff --git a/target/s390x/kvm/kvm.c b/target/s390x/kvm/kvm.c index 1b494ecc20..132952cc84 100644 --- a/target/s390x/kvm/kvm.c +++ b/target/s390x/kvm/kvm.c @@ -865,7 +865,8 @@ static void determine_sw_breakpoint_instr(void) } } -int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) +int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) { determine_sw_breakpoint_instr(); @@ -877,7 +878,8 @@ int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) return 0; } -int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) +int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp, + vaddr len) { uint8_t t[MAX_ILEN]; -- 2.17.1