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Date:   Tue, 19 Jun 2018 11:35:52 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Zhenzhong Duan <zhenzhong.duan@oracle.com>
Cc:     Linux-Kernel <linux-kernel@vger.kernel.org>, mingo@redhat.com,
        tglx@linutronix.de, Srinivas REDDY Eeda <srinivas.eeda@oracle.com>,
        hpa@zytor.com
Subject: Re: [PATCH] x86/microcode/intel: Ensure new microcode processor
 flags match with cpu's pf
Message-ID: <20180619093552.GB30870@zn.tnic>
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 <ed92d414-9869-cd06-eee1-1035cc574cf4@oracle.com>
 <20180619091205.GA30870@zn.tnic>
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On Tue, Jun 19, 2018 at 05:24:20PM +0800, Zhenzhong Duan wrote:
> On 2018/6/19 17:12, Borislav Petkov wrote:
> > On Tue, Jun 19, 2018 at 12:49:40PM +0800, Zhenzhong Duan wrote:
> > > Imagine kernel already found a microcode blob A with extended sig/pf
> > > matching current cpu, then another microcode B is checked which doesn't
> > > match current cpu...
> > Do you see the
> > 
> > 	if (!microcode_matches(mc_header, uci->cpu_sig.sig)) {
> > 
> > call a couple of lines earlier?
> Sure, but it didn't ensure a match in stepping and pf, is that expected?

Do you see the

	if (!has_newer_microcode(data,
				 uci->cpu_sig.sig,
                                 uci->cpu_sig.pf,
                                 uci->cpu_sig.rev))

a couple lines later?

-- 
Regards/Gruss,
    Boris.

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