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Date:   Fri, 1 Dec 2023 11:37:33 +0100
From:   Michal Hocko <mhocko@suse.com>
To:     Pingfan Liu <piliu@redhat.com>
Cc:     Baoquan He <bhe@redhat.com>, Donald Dutile <ddutile@redhat.com>,
        Jiri Bohac <jbohac@suse.cz>, 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 08:54:20, Pingfan Liu wrote:
[...]
> > I am not aware of any method to detect a driver is going to configure a
> > RDMA.
> >
> 
> If there is a pattern, scripts/coccinelle may give some help. But I am
> not sure about that.

I am not aware of any pattern.

> > > If this can be resolved, I think this method is promising.
> >
> > Are you indicating this is a mandatory prerequisite?
> 
> IMHO, that should be mandatory. Otherwise for any unexpected kdump
> kernel collapses,  it can not shake off its suspicion.

I appreciate your carefulness! But I do not really see how such a
detection would work and be maintained over time. What exactly is the
scope of such a tooling? Should it be limited to RDMA drivers? Should we
protect from stray writes in general?

Also to make it clear. Are you going to nak the proposed solution if
there is no such tooling available?
-- 
Michal Hocko
SUSE Labs