Date: Thu, 4 Jan 2018 02:27:54 +0100 (CET)
From: Jiri Kosina <jikos@kernel.org>
To: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Dan Williams <dan.j.williams@intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        linux-arch@vger.kernel.org, Peter Zijlstra <peterz@infradead.org>,
        Greg KH <gregkh@linuxfoundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Elena Reshetova <elena.reshetova@intel.com>,
        Alan Cox <alan@linux.intel.com>
Subject: Re: [RFC PATCH] asm/generic: introduce if_nospec and
 nospec_barrier
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On Thu, 4 Jan 2018, Alan Cox wrote:

> There are people trying to tune coverity and other tool rules to identify
> cases, 

Yeah, but that (and *especially* Coverity) is so inconvenient to be 
applied to each and every patch ... that this is not the way to go.

If the CPU speculation can cause these kinds of side-effects, it just must 
not happen, full stop. OS trying to work it around is just a whack-a-mole 
(which we can apply for old silicon, sure ... but not something that 
becomes a new standard) that's never going to lead to any ultimate 
solution.

-- 
Jiri Kosina
SUSE Labs