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Date:   Thu, 12 May 2022 10:43:25 -0700
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     Michael Ellerman <mpe@ellerman.id.au>
Cc:     Herbert Xu <herbert@gondor.apana.org.au>,
        linux-kernel@vger.kernel.org, linux-modules@vger.kernel.org,
        fnovak@us.ibm.com, linuxppc-dev@ozlabs.org,
        christophe.leroy@csgroup.eu
Subject: Re: request_module DoS
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On Thu, May 12, 2022 at 10:07:26PM +1000, Michael Ellerman wrote:
> Michael Ellerman <mpe@ellerman.id.au> writes:
> > Luis Chamberlain <mcgrof@kernel.org> writes:
> ...
> >
> >> Can someone try this on ppc64le system? At this point I am not convinced
> >> this issue is generic.
> >
> > Does your x86 system have at least 784 CPUs?
> >
> > I don't know where the original report came from, but the trace shows
> > "CPU 784", which would usually indicate a system with at least that many
> > CPUs.
> 
> Update, apparently the report originally came from IBM, so I'll chase it
> up internally.
> 
> I think you're right that there's probably no issue in the module code,
> sorry to waste your time.

It gives me testing happiness to know that may be the case :)

  Luis