linux-kernel - Re: [PATCH RFC] x86, tsc: Allow for high latency in quick_pit

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: <5587EFC5.5010303@intel.com>
Date:	Mon, 22 Jun 2015 14:21:41 +0300
From:	Adrian Hunter <adrian.hunter@...el.com>
To:	Thomas Gleixner <tglx@...utronix.de>
CC:	Andi Kleen <ak@...ux.intel.com>,
	Andy Lutomirski <luto@...capital.net>,
	LKML <linux-kernel@...r.kernel.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	X86 ML <x86@...nel.org>, "H. Peter Anvin" <hpa@...or.com>,
	Len Brown <lenb@...nel.org>,
	George Spelvin <linux@...izon.com>,
	Ingo Molnar <mingo@...nel.org>, a.p.zijlstra@...llo.nl,
	arjan@...radead.org, bp@...en8.de, penberg@....fi,
	akpm@...ux-foundation.org
Subject: Re: [PATCH RFC] x86, tsc: Allow for high latency in quick_pit_calibrate()

On 03/06/15 19:23, Thomas Gleixner wrote:
> On Wed, 3 Jun 2015, Adrian Hunter wrote:
> 
>> On 03/06/15 06:30, Andi Kleen wrote:
>>>> Then the changelog should say that I think.  The current text says
>>>> "Fast TSC calibration will always fail", which, to me, suggests that
>>>> either the slow calibration will work or that the changelog message
>>>> should be changed.
>>>
>>> Ok. No, the slow calibration works I believe.
>>
>> Yeah, so the (only?) downside is the 50ms wasted on Fast TSC
>> calibration.  What about this?
> 
> I'm certainly happy to apply this one. 

George Spelvin began investigating improving quick_pit_calibrate() but Ingo
anyway suggested this patch as the first, so can this be applied?

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
Please read the FAQ at  http://www.tux.org/lkml/