From mboxrd@z Thu Jan  1 00:00:00 1970
From: Borislav Petkov <bp@suse.de>
Subject: Re: [PATCH v6 5/5] x86/kvm: Avoid dynamic allocation of pvclock data
 when SEV is active
Date: Mon, 10 Sep 2018 17:53:29 +0200
Message-ID: <20180910155329.GB20286@zn.tnic>
References: <1536343050-18532-1-git-send-email-brijesh.singh@amd.com>
 <1536343050-18532-6-git-send-email-brijesh.singh@amd.com>
 <20180910122727.GE21815@zn.tnic>
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Cc: x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>
To: Brijesh Singh <brijesh.singh@amd.com>
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On Mon, Sep 10, 2018 at 08:15:38AM -0500, Brijesh Singh wrote:
> > Now, the real question from all this SNAFU is, why can't all those point
> > to a single struct pvclock_vsyscall_time_info and all CPUs read a single
> > thing? Why do they have to be per-CPU and thus waste so much memory?

You forgot to answer to the real question - why do we need those things
to be perCPU and why can't we use a single instance to share with *all*
CPUs?

Because if we can, then we're golden!

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--