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Date:   Mon, 11 Jul 2022 08:57:25 -0700
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     Aaron Tomlin <atomlin@atomlin.com>,
        Adrian Hunter <adrian.hunter@intel.com>
Cc:     Aaron Tomlin <atomlin@redhat.com>, rostedt@goodmis.org,
        cl@linux.com, pmladek@suse.com, mbenes@suse.cz,
        christophe.leroy@csgroup.eu, akpm@linux-foundation.org,
        linux-kernel@vger.kernel.org, linux-modules@vger.kernel.org,
        ghalat@redhat.com, oleksandr@natalenko.name, neelx@redhat.com,
        daniel.thompson@linaro.org, hch@infradead.org, tglx@linutronix.de,
        linux-rt-users@vger.kernel.org
Subject: Re: [PATCH v2] module: kallsyms: Ensure preemption in add_kallsyms()
 with PREEMPT_RT
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Sender: Luis Chamberlain <mcgrof@infradead.org>
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On Thu, Jul 07, 2022 at 07:56:19PM +0100, Aaron Tomlin wrote:
> On Thu 2022-07-07 10:20 -0700, Luis Chamberlain wrote:
> > This is incredibly important information which should be added to the
> > commit log, specialy as PREEMPT_RT=y becomes a first class citizen.
> 
> Understood.
> 
> > 
> > > So, I would say this was a regression since earlier preemption was
> > > not disabled and we would dereference RCU-protected pointers explicitly
> > > i.e. without using the more appropriate rcu_dereference() family
> > > of primitives. That being said, these pointers cannot change in this
> > > context as explained previously.
> > > 
> > > Would the above be suitable - just to confirm before I send another
> > > iteration?
> > 
> > Yes, I would send this to Linus for the rc series. Please adjust the
> > commit log with all this information.
> 
> Will do.
> 
> > BTW I think there is just one more fix pending from you right?
> 
> Yes - I will send/or prepare it as a partial revert:
> 's/strscpy/strlcpy/' with a brief explanation.

If that is just the kallsyms fix Adrian Hunter already sent a fix:

https://lkml.kernel.org/r/20220701094403.3044-1-adrian.hunter@intel.com         

  Luis