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From:   Michael Ellerman <mpe@ellerman.id.au>
To:     Luis Chamberlain <mcgrof@kernel.org>
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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Date:   Thu, 12 May 2022 22:07:26 +1000
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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.

cheers