Re: [RFC PATCH 1/1] QEMU plugin interface extension

[Peter Maydell]

On Sat, 21 Aug 2021 at 10:48, Florian Hauschild
<florian.hauschild@fs.ei.tum.de> wrote:
>
> This extension covers functions:
>   * to read and write guest memory
>   * to read and write guest registers
>   * to flush tb cache
>   * to control single stepping of qemu from plugin
>
> These changes allow the user to
>   * collect more information about the behaviour of the system
>   * change the guest state with a plugin during execution
>   * control cache of tcg
>   * allow for precise instrumentation in execution flow

> +
> +static int plugin_read_register(CPUState *cpu, GByteArray *buf, int reg)
> +{
> +    CPUClass *cc = CPU_GET_CLASS(cpu);
> +    if (reg < cc->gdb_num_core_regs) {
> +        return cc->gdb_read_register(cpu, buf, reg);
> +    }
> +    return 0;
> +}

At the point where these functions execute is the emulation
definitely stopped (ie no register values currently held
live in TCG locals) ?

-- PMM