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Date:   Fri, 19 Apr 2019 22:52:01 +0200 (CEST)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Jacob Pan <jacob.jun.pan@linux.intel.com>
cc:     Daniel Drake <drake@endlessm.com>, Len Brown <lenb@kernel.org>,
        x86@kernel.org, LKML <linux-kernel@vger.kernel.org>,
        linux@endlessm.com, rjw@rjwysocki.net,
        "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Subject: Re: Detecting x86 LAPIC timer frequency from CPUID data
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On Fri, 19 Apr 2019, Jacob Pan wrote:
> On Fri, 19 Apr 2019 10:57:10 +0200 (CEST)
> Thomas Gleixner <tglx@linutronix.de> wrote:
> > On Fri, 19 Apr 2019, Daniel Drake wrote:
> > > 0x7FFFFF vs 0x7FFFFFFF, is that intentional?  
> > 
> > I don't think so. Looks like a failed copy and paste. Cc'ed Jacob, he
> > might know.
> > 
> At the time of v2.6.35 both places use 0x7FFFFF. But later this patch
> increased the latter to 0x7FFFFFFF but forgot the first part. So I
> guess it is not exactly a failed copy and paste.
> 
> commit 4aed89d6b515b9185351706ca95cd712c9d8d6a3
> Author: Pierre Tardy <pierre.tardy@intel.com>
> Date:   Thu Jan 6 16:23:29 2011 +0100
> 
>     x86, lapic-timer: Increase the max_delta to 31 bits

Indeed. Thanks for digging that up!

	tglx