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From:   David Howells <dhowells@redhat.com>
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To:     Jann Horn <jannh@google.com>
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Subject: Re: [PATCH] cred: Use RCU primitives to access RCU pointers
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Date:   Fri, 31 Jan 2020 17:49:49 +0000
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Jann Horn <jannh@google.com> wrote:

> > task_struct.cred and task_struct.real_cred are annotated by __rcu,
> 
> task_struct.cred doesn't actually have RCU semantics though, see
> commit d7852fbd0f0423937fa287a598bfde188bb68c22. For task_struct.cred,
> it would probably be more correct to remove the __rcu annotation?

You're right, I think, there shouldn't be any need for __rcu on
task_struct::cred since it shouldn't be accessed on any task except current.

I've a feeling that there was something at the time, proc perhaps, but I don't
remember.

David