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Date:   Tue, 19 Jun 2018 22:57:35 +0200 (CEST)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Peter Zijlstra <peterz@infradead.org>
cc:     Pavel Tatashin <pasha.tatashin@oracle.com>,
        steven.sistare@oracle.com, daniel.m.jordan@oracle.com,
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Subject: Re: [PATCH v10 1/7] x86/tsc: remove tsc_disabled flag
In-Reply-To: <20180619200115.GH2494@hirez.programming.kicks-ass.net>
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On Tue, 19 Jun 2018, Peter Zijlstra wrote:

> On Tue, Jun 19, 2018 at 09:12:45PM +0200, Thomas Gleixner wrote:
> > On Tue, 19 Jun 2018, Peter Zijlstra wrote:
> > > It does not; there is TSC usage even if you boot with notsc on. See how
> > > it does not clear X86_FEATURE_TSC for instance.
> > 
> > Well, kinda. There is some stuff in the apic calibration which uses TSC
> > independent of tsc_disabled, but that's about it.
> 
> Still, that precludes booting on hardware without TSC, so what's the
> point of having notsc? I'm all for killing the thing.

I'm not arguing against removing it. I just refuse to accept changelogs
which suggest that there is no functional change.

Thanks,

	tglx