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Date:   Mon, 10 Sep 2018 21:14:11 +0200 (CEST)
From:   Jiri Kosina <jikos@kernel.org>
To:     "Schaufler, Casey" <casey.schaufler@intel.com>
cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        "Woodhouse, David" <dwmw@amazon.co.uk>,
        Andi Kleen <ak@linux.intel.com>,
        Tim Chen <tim.c.chen@linux.intel.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "x86@kernel.org" <x86@kernel.org>
Subject: RE: [PATCH v5 1/2] x86/speculation: apply IBPB more strictly to
 avoid cross-process data leak
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On Mon, 10 Sep 2018, Schaufler, Casey wrote:

> Why are you dropping the LSM check here, when in v4 you fixed the
> SELinux audit locking issue? We can avoid introducing an LSM hook
> and all the baggage around it if you can do the security_ptrace_access_check()
> here.

So what guarantees that none of the hooks that 
security_ptrace_access_check() is invoking will not be taking locks (from 
scheduler context in this case)?

Thanks,

-- 
Jiri Kosina
SUSE Labs