Message-ID: <fb72e7ae7b78e75a53acdb62960bdee8de5cb207.camel@infradead.org>
Subject: Re: [External] Re: [PATCH v6 06/11] x86/smpboot: Support parallel
 startup of secondary CPUs
From:   David Woodhouse <dwmw2@infradead.org>
To:     Usama Arif <usama.arif@bytedance.com>, tglx@linutronix.de,
        arjan@linux.intel.com
Cc:     mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com,
        hpa@zytor.com, x86@kernel.org, pbonzini@redhat.com,
        paulmck@kernel.org, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, rcu@vger.kernel.org, mimoja@mimoja.de,
        hewenliang4@huawei.com, thomas.lendacky@amd.com, seanjc@google.com,
        pmenzel@molgen.mpg.de, fam.zheng@bytedance.com,
        punit.agrawal@bytedance.com, simon.evans@bytedance.com,
        liangma@liangbit.com
Date:   Fri, 03 Feb 2023 08:14:12 +0000
In-Reply-To: <fb3e75fa-1a6f-0570-218f-ba9133fb72c6@bytedance.com>
References: <20230202215625.3248306-1-usama.arif@bytedance.com>
         <20230202215625.3248306-7-usama.arif@bytedance.com>
         <dac090d2a61137b9e2fecd6cb3bfb4d5a9656fb6.camel@infradead.org>
         <fb3e75fa-1a6f-0570-218f-ba9133fb72c6@bytedance.com>
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On Thu, 2023-02-02 at 22:50 +0000, Usama Arif wrote:
>=20
> Ah, sorry about that, should have caught it while reviewing before=20
> posting. To think of it, it might be better to squash this and next AMD=
=20
> disabling patch, if anyone testing on AMD ever happens to check out at=
=20
> this specific patch, their machine might not boot :).=C2=A0
>=20

Nah, we don't actually *enable* parallel boot until the next patch
anyway. At this point we're only laying the groundwork. I think it's
best separate.

> Will repost only after getting the OK for the rest of the patches
> along with addressing any other comments that come up.

Ack. And hopefully the missing SoB from both Thomas and Arjan for their
parts. Part of the reasoning for the lack of SoB from Arjan might have
been that we haven't finished doing the thinking about how this works
in all cases, with non-constant TSC and other stuff. Let's make sure we
give that a long hard stare.

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