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Date:   Thu, 4 Oct 2018 09:47:25 +0200 (CEST)
From:   Jiri Kosina <jikos@kernel.org>
To:     Jann Horn <jannh@google.com>
cc:     Casey Schaufler <casey.schaufler@intel.com>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        kernel list <linux-kernel@vger.kernel.org>,
        linux-security-module <linux-security-module@vger.kernel.org>,
        selinux@tycho.nsa.gov, Dave Hansen <dave.hansen@intel.com>,
        deneen.t.dock@intel.com, kristen@linux.intel.com,
        Arjan van de Ven <arjan@linux.intel.com>
Subject: Re: [PATCH v5 2/5] Smack: Prepare for PTRACE_MODE_SCHED
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On Thu, 27 Sep 2018, Jann Horn wrote:

> > Yes. Since the PTRACE_MODE_NOAUDIT was in PTRACE_MODE_IBPB in Jiri's 
> > previous patch set and not in PTRACE_MODE_SCHED in this one I assumed 
> > that there was a good reason for it.
> 
> Jiri, was there a good reason for it, and if so, what was it?

[ FWIW PTRACE_MODE_NOAUDIT being in PTRACE_MODE_IBPB goes back to original 
  Tim's pre-CRD patchset ]

Well, we can't really call out into audit from scheduler code, and the 
previous versions of the patchsets didn't have PTRACE_MODE_SCHED, so it 
had to be included in PTRACE_MODE_IBPB in order to make sure we're not 
calling into audit from context switch code.

Or did I misunderstand the question?

Thanks,

-- 
Jiri Kosina
SUSE Labs