target-arm: Fix CPU breakpoint handling

A QEMU breakpoint match is not definitely an architectural breakpoint
match. If an exception is generated unconditionally during translation,
it is hardly possible to ignore it in the debug exception handler.

Generate a call to a helper to check CPU breakpoints and raise an
exception only if any breakpoint matches architecturally.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Sergey Fedorov 2015-10-13 12:56:28 +03:00 committed by Peter Maydell
parent e63a2d4d9e
commit 5d98bf8f38
4 changed files with 46 additions and 21 deletions

View File

@ -54,6 +54,8 @@ DEF_HELPER_1(yield, void, env)
DEF_HELPER_1(pre_hvc, void, env)
DEF_HELPER_2(pre_smc, void, env, i32)
DEF_HELPER_1(check_breakpoints, void, env)
DEF_HELPER_3(cpsr_write, void, env, i32, i32)
DEF_HELPER_1(cpsr_read, i32, env)

View File

@ -867,6 +867,15 @@ static bool check_breakpoints(ARMCPU *cpu)
return false;
}
void HELPER(check_breakpoints)(CPUARMState *env)
{
ARMCPU *cpu = arm_env_get_cpu(env);
if (check_breakpoints(cpu)) {
HELPER(exception_internal(env, EXCP_DEBUG));
}
}
void arm_debug_excp_handler(CPUState *cs)
{
/* Called by core code when a watchpoint or breakpoint fires;
@ -898,23 +907,21 @@ void arm_debug_excp_handler(CPUState *cs)
}
} else {
uint64_t pc = is_a64(env) ? env->pc : env->regs[15];
bool same_el = (arm_debug_target_el(env) == arm_current_el(env));
if (cpu_breakpoint_test(cs, pc, BP_GDB)) {
return;
}
if (check_breakpoints(cpu)) {
bool same_el = (arm_debug_target_el(env) == arm_current_el(env));
if (extended_addresses_enabled(env)) {
env->exception.fsr = (1 << 9) | 0x22;
} else {
env->exception.fsr = 0x2;
}
/* FAR is UNKNOWN, so doesn't need setting */
raise_exception(env, EXCP_PREFETCH_ABORT,
syn_breakpoint(same_el),
arm_debug_target_el(env));
if (extended_addresses_enabled(env)) {
env->exception.fsr = (1 << 9) | 0x22;
} else {
env->exception.fsr = 0x2;
}
/* FAR is UNKNOWN, so doesn't need setting */
raise_exception(env, EXCP_PREFETCH_ABORT,
syn_breakpoint(same_el),
arm_debug_target_el(env));
}
}

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@ -11090,11 +11090,18 @@ void gen_intermediate_code_a64(ARMCPU *cpu, TranslationBlock *tb)
CPUBreakpoint *bp;
QTAILQ_FOREACH(bp, &cs->breakpoints, entry) {
if (bp->pc == dc->pc) {
gen_exception_internal_insn(dc, 0, EXCP_DEBUG);
/* Advance PC so that clearing the breakpoint will
invalidate this TB. */
dc->pc += 2;
goto done_generating;
if (bp->flags & BP_CPU) {
gen_helper_check_breakpoints(cpu_env);
/* End the TB early; it likely won't be executed */
dc->is_jmp = DISAS_UPDATE;
} else {
gen_exception_internal_insn(dc, 0, EXCP_DEBUG);
/* Advance PC so that clearing the breakpoint will
invalidate this TB. */
dc->pc += 4;
goto done_generating;
}
break;
}
}
}

View File

@ -11342,11 +11342,20 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
CPUBreakpoint *bp;
QTAILQ_FOREACH(bp, &cs->breakpoints, entry) {
if (bp->pc == dc->pc) {
gen_exception_internal_insn(dc, 0, EXCP_DEBUG);
/* Advance PC so that clearing the breakpoint will
invalidate this TB. */
dc->pc += 2;
goto done_generating;
if (bp->flags & BP_CPU) {
gen_helper_check_breakpoints(cpu_env);
/* End the TB early; it's likely not going to be executed */
dc->is_jmp = DISAS_UPDATE;
} else {
gen_exception_internal_insn(dc, 0, EXCP_DEBUG);
/* Advance PC so that clearing the breakpoint will
invalidate this TB. */
/* TODO: Advance PC by correct instruction length to
* avoid disassembler error messages */
dc->pc += 2;
goto done_generating;
}
break;
}
}
}