netdev - Re: [PATCH net-next V3 1/2] igb: add PTP Hardware Clock code

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20120110093349.GA5480@cherladcori01>
Date:	Tue, 10 Jan 2012 10:33:49 +0100
From:	Richard Cochran <richardcochran@...il.com>
To:	"Keller, Jacob E" <jacob.e.keller@...el.com>
Cc:	"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
	"e1000-devel@...ts.sourceforge.net" 
	<e1000-devel@...ts.sourceforge.net>,
	"Kirsher, Jeffrey T" <jeffrey.t.kirsher@...el.com>,
	"Ronciak, John" <john.ronciak@...el.com>,
	John Stultz <john.stultz@...aro.org>,
	Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH net-next V3 1/2] igb: add PTP Hardware Clock code

On Tue, Jan 10, 2012 at 09:44:50AM +0100, Richard Cochran wrote:
> On Mon, Jan 09, 2012 at 05:42:20PM +0000, Keller, Jacob E wrote:
> 
> > Is there a reason for not using the timecounter structure from the
> > kernel? It is a layer beneath the timecompare code which is meant to
> > handle this condition. As far as I can tell this issue is solved in
> > the timecounter code. If it is not, then that should be a bug in the
> > timecounter cyclecounter code. I don't know if this issue occurs in
> > the timecounter structure because it handles the ns conversion
> > differently.
> 
> My only reason is that I am not sure that the timecounter code really
> does what we need.  It might well work.  Consider, though, that the
> 82580 register does not overflow in the usual way. The upper 24 bits
> are always zero.
> 
> What I wrote does the right thing, I think.  However, duplicated
> effort is always bad, so can you show me how to change it?

I took a brief look, and I think the timecounter idea might work.
Later this week I'll try it out if I can.

Thanks,
Richard

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html