Re: [PATCH v3 2/8] cxl/acpi: Add root device lockdep validation

From: Peter Zijlstra
Date: Mon Apr 25 2022 - 06:34:00 EST

On Sat, Apr 23, 2022 at 10:27:52AM -0700, Dan Williams wrote:

> I'm going to drop it and just add a comment about the
> expectations. As Peter said there's already a multitude of ways to
> cause false positive / negative results with lockdep so this is just
> one more area where one needs to be careful and understand the lock
> context they might be overriding.

One safe-guard might be to check the class you're overriding is indeed
__no_validate__, and WARN if not. Then the unconditional reset is

Then, if/when, that WARN ever triggers you can revisit all this.