Re: [PATCH v3 5/5] platform/x86: think-lmi: mutex protection around multiple WMI calls

From: Mark Pearson
Date: Mon May 29 2023 - 10:04:34 EST

Hi Ilpo,

On Mon, May 29, 2023, at 8:23 AM, Ilpo Järvinen wrote:
> On Fri, 26 May 2023, Mark Pearson wrote:
>> Add mutex protection around cases where an operation needs multiple
>> WMI calls - e.g. setting password.
> So you need this feature already for Patch 1/5? If that's the case, you
> should reorder the patches and put it before 1/5.

You're right....I was being lazy and just adding it to the end of the series as it was easier. I can re-order.

As a side note, the chances of two people changing things on a system at the same time is rather unlikely - it just doesn't make sense as it's something done by an administrator. But a fix is a fix.

> That "e.g. setting password" sounds vague enough that I'm left to wonder
> if there are other cases in the driver which need locking too. It would be
> useful to be precise with wording here. It will help immensely when
> somebody looks this changelog 5 years from now if you explain all cases
> that need locking up front.

OK. There are two cases and I can list both cases explicitly.

> So, is this needed also for some existing code, then Fixes tag might be in
> order? (I'm looking e.g. that cert auth block in current_value_store()
> which also does more than one call).

True - I can add that.

Thanks for the review. I'll hold off a couple of days before making those changes in case there is any feedback