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Date:   Mon, 19 Nov 2018 00:01:26 +0100 (CET)
From:   Jiri Kosina <jikos@kernel.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
cc:     Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        David Woodhouse <dwmw@amazon.co.uk>,
        Andi Kleen <ak@linux.intel.com>,
        Tim Chen <tim.c.chen@linux.intel.com>,
        Casey Schaufler <casey.schaufler@intel.com>,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        the arch/x86 maintainers <x86@kernel.org>,
        stable@vger.kernel.org
Subject: Re: STIBP by default.. Revert?
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On Sun, 18 Nov 2018, Jiri Kosina wrote:

> It's probably not just browsers, but anything running JITed sandboxed 
> code. So the most straightforward way might be the prctl() aproach, where 
> userspace would claim "I do care about this, please fix it up for me". So 
> prctl() + perhaps SECCOMP.

I've just sent SECCOMP handling as a followup to Tim's set.

I still feel like we should make STIBP and IBPB behavior consistent (in a 
sense they should always be used both, or none of them), but that might be 
additional 4.21 optimization.

Thanks,

-- 
Jiri Kosina
SUSE Labs