Re: [PATCH] nvme-core: remove head->effects to fix use-after-free

From: Christoph Hellwig
Date: Mon Nov 20 2023 - 03:23:55 EST


On Fri, Nov 17, 2023 at 09:38:19AM -0700, Keith Busch wrote:
> The effects log is per-CSI so different command sets won't create
> conflicts.

True. But that wasn't the point anyway. It is that different
controllers might expose very different namespaes with different
capabilities. Maybe a controller with HDD namespaces vs flash might
be a better example.

> Namespaces that are not shared don't really matter here because this
> problem is unique to mulitpath.

Indeed.

> It doesn't make sense for effects logs to be different per-controller
> for the same shared namespace. The spec doesn't seem to explicitly
> prevent that, but hints that all hosts should be seeing the same thing
> no matter which controller they're connected to:

Also agreed as already indicated in the past mail.