Re: [PATCH v16 17/18] plugins: Allow to read registers

[Alex Bennée]

Akihiko Odaki <akihiko.odaki@daynix.com> writes:

> It is based on GDB protocol to ensure interface stability.
>
> The timing of the vcpu init hook is also changed so that the hook will
> get called after GDB features are initialized.

I guess this was moved into an earlier patch.
>  }
> +
> +int qemu_plugin_find_register_file(unsigned int vcpu_index, const char *name)
> +{
> +    QEMU_IOTHREAD_LOCK_GUARD();

What is this lock protecting against?

gdb_register_feature doesn't protect cpu->gdb_regs() when registering
features as it is implicitly per-CPU.

If GDB should be locking I would push that down into gdbstub itself (and
not use the global IOTHREAD).

> +    return gdb_find_feature(qemu_get_cpu(vcpu_index), name);
> +}
> +
> +int qemu_plugin_find_register(unsigned int vcpu_index, int file,
> +                              const char *name)
> +{
> +    QEMU_IOTHREAD_LOCK_GUARD();
> +    return gdb_find_feature_register(qemu_get_cpu(vcpu_index), file, name);
> +}
> +

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro