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Date:   Fri, 1 Dec 2023 12:55:52 +0100
From:   Michal Hocko <mhocko@suse.com>
To:     Philipp Rudo <prudo@redhat.com>
Cc:     Baoquan He <bhe@redhat.com>, Donald Dutile <ddutile@redhat.com>,
        Jiri Bohac <jbohac@suse.cz>, Pingfan Liu <piliu@redhat.com>,
        Tao Liu <ltao@redhat.com>, Vivek Goyal <vgoyal@redhat.com>,
        Dave Young <dyoung@redhat.com>, kexec@lists.infradead.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/4] kdump: crashkernel reservation from CMA
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On Fri 01-12-23 12:33:53, Philipp Rudo wrote:
[...]
> And yes, those are all what-if concerns but unfortunately that is all
> we have right now.

Should theoretical concerns without an actual evidence (e.g. multiple
drivers known to be broken) become a roadblock for this otherwise useful
feature? 

> Only alternative would be to run extended tests in
> the field. Which means this user facing change needs to be included.
> Which also means that we are stuck with it as once a user facing change
> is in it's extremely hard to get rid of it again...

I am not really sure I follow you here. Are you suggesting once
crashkernel=cma is added it would become a user api and therefore
impossible to get rid of?

-- 
Michal Hocko
SUSE Labs