On 03/20/2018 10:41 AM, Peter Maydell wrote:
> Now that we have a helper function specifically for the BRK and
> BKPT instructions, we can set the exception.fsr there rather
> than in arm_cpu_do_interrupt_aarch32(). This allows us to
> use our new arm_debug_exception_fsr() helper.
>
> In particular this fixes a bug where we were hardcoding the
> short-form IFSR value, which is wrong if the target exception
> level has LPAE enabled.
>
> Fixes: https://bugs.launchpad.net/qemu/+bug/1756927
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
> target/arm/helper.c | 1 -
> target/arm/op_helper.c | 2 ++
> 2 files changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index 09893e3f72..dcb8476d9e 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -7910,7 +7910,6 @@ static void arm_cpu_do_interrupt_aarch32(CPUState *cs)
> offset = 0;
> break;
> case EXCP_BKPT:
> - env->exception.fsr = 2;
> /* Fall through to prefetch abort. */
> case EXCP_PREFETCH_ABORT:
> A32_BANKED_CURRENT_REG_SET(env, ifsr, env->exception.fsr);
> diff --git a/target/arm/op_helper.c b/target/arm/op_helper.c
> index 75efff9edf..8e1e521193 100644
> --- a/target/arm/op_helper.c
> +++ b/target/arm/op_helper.c
> @@ -488,6 +488,8 @@ void HELPER(exception_with_syndrome)(CPUARMState *env, uint32_t excp,
> */
> void HELPER(exception_bkpt_insn)(CPUARMState *env, uint32_t syndrome)
> {
> + /* FSR will only be used if the debug target EL is AArch32. */
> + env->exception.fsr = arm_debug_exception_fsr(env);
> raise_exception(env, EXCP_BKPT, syndrome, arm_debug_target_el(env));
> }
>
>