Re: [Qemu-devel] [PATCH] Fix breakpoint support in Nios II user-mode emulation.

[Peter Maydell]

On Wed, 13 Feb 2019 at 17:19, Sandra Loosemore <address@hidden> wrote:
>
> Nios II user-mode emulation was missing handling for EXCP_DEBUG,
> making the gdb stub essentially useless.  This patch adds the missing
> piece.  The new code was copied from the existing EXCP_TRAP handling
> and is also similar to what other targets (e.g., arm) do with EXCP_DEBUG.
>
> Signed-off-by: Sandra Loosemore <address@hidden>
> ---
>  linux-user/nios2/cpu_loop.c | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/linux-user/nios2/cpu_loop.c b/linux-user/nios2/cpu_loop.c
> index b96b1aa..5aa1eca 100644
> --- a/linux-user/nios2/cpu_loop.c
> +++ b/linux-user/nios2/cpu_loop.c
> @@ -73,6 +73,12 @@ void cpu_loop(CPUNios2State *env)
>                  queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
>                  break;
>              }
> +        case EXCP_DEBUG:
> +            info.si_signo = TARGET_SIGTRAP;
> +            info.si_errno = 0;
> +            info.si_code = TARGET_TRAP_BRKPT;
> +            queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
> +            break;
>          case 0xaa:
>              switch (env->regs[R_PC]) {
>              /*case 0x1000:*/  /* TODO:__kuser_helper_version */

I don't know NiosII at all, but a quick check of the kernel
sources suggests this is correct, so

Reviewed-by: Peter Maydell <address@hidden>

thanks
-- PMM