Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Fri, 15 Jul 2022 15:19:01 -0700
From:   Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Naresh Kamboju <naresh.kamboju@linaro.org>,
        open list <linux-kernel@vger.kernel.org>,
        X86 ML <x86@kernel.org>, lkft-triage@lists.linaro.org,
        Borislav Petkov <bp@suse.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Josh Poimboeuf <jpoimboe@kernel.org>
Subject: Re: RETBleed: WARNING: Spectre v2 mitigation leaves CPU vulnerable
 to RETBleed attacks, data leaks possible!
Message-ID: <20220715221901.xm3c4w4idqt67uja@desk>
References: <CA+G9fYv0N0FcYRp5irO_7TpheLcUY8LRMQbcZqwEmiRTEccEjA@mail.gmail.com>
 <Ys/bWIk0F5srkkpF@kroah.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <Ys/bWIk0F5srkkpF@kroah.com>
Precedence: bulk

On Thu, Jul 14, 2022 at 11:01:12AM +0200, Greg Kroah-Hartman wrote:
> On Thu, Jul 14, 2022 at 02:15:07PM +0530, Naresh Kamboju wrote:
> > Results from Linaro’s test farm.
> > 
> > We are booting the i386 kernel on an x86 machine.
> > With Spectre V2 patches merged into Linux mainline we have been noticing
> > RETBleed: WARNING: Spectre v2 mitigation leaves CPU vulnerable to
> > RETBleed attacks, data leaks possible!
> 
> That's funny.  I don't think that's a valid combination that should be
> cared about, but I'll leave it to Pawan to comment if it is something
> that is "real" to be concerned for.

Intel is not aware of production environments that use 32-bit mode on
Skylake-gen CPUs. So this should not be a concern.

Thanks,
Pawan