Re: [RFC PATCH v2 0/7] tcg-plugins: add hooks for interrupts, exceptions and traps

["Alex Bennée" <alex.bennee@linaro.org>]

Pierrick Bouvier <pierrick.bouvier@linaro.org> writes:

> Hi Julian,
>
> On 10/19/24 09:39, Julian Ganz wrote:
>> Some analysis greatly benefits, or depends on, information about
>> interrupts. For example, we may need to handle the execution of a new
>> translation block differently if it is not the result of normal program
>> flow but of an interrupt.
>> Even with the existing interfaces, it is more or less possible to
>> discern these situations, e.g. as done by the cflow plugin. However,
>> this process poses a considerable overhead to the core analysis one may
>> intend to perform.
>>
>
> I agree it would be useful. Beyond the scope of this series, it would
> be nice if we could add a control flow related API instead of asking
> to plugins to do it themselves.

I think there is a balance to be had here. We don't want to
inadvertently expose QEMU internals to the plugin API. With this series
at least we rely on stuff the front-end knows which can at least be
tweaked relatively easily.

> If we would provide something like this, is there still a value to add
> an API to detect interrupt/exceptions/traps events?
>
> Note: It's not a critic against what you sent, just an open question
> on *why* it's useful to access this QEMU implementation related
> information vs something more generic.
<snip>

It would be good to have the opinion of the front-end maintainers if
this is too burdensome or easy enough to manage.


-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro