From: Dave Hansen <dave.hansen@intel.com>
To: Peter Zijlstra <peterz@infradead.org>, gratian.crisan@ni.com
Cc: Thomas Gleixner <tglx@linutronix.de>,
linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
"H . Peter Anvin" <hpa@zytor.com>,
x86@kernel.org, Borislav Petkov <bp@alien8.de>,
Josh Cartwright <joshc@ni.com>,
gratian@gmail.com
Subject: Re: [RFC PATCH] tsc: synchronize TSCs on buggy Intel Xeon E5 CPUs with offset error
Date: Fri, 13 Nov 2015 13:13:29 -0800 [thread overview]
Message-ID: <56465279.2010502@intel.com> (raw)
In-Reply-To: <20151109220232.GO17308@twins.programming.kicks-ass.net>
On 11/09/2015 02:02 PM, Peter Zijlstra wrote:
> On Mon, Nov 09, 2015 at 01:59:02PM -0600, gratian.crisan@ni.com wrote:
>> The Intel Xeon E5 processor family suffers from errata[1] BT81:
>
>> +#ifdef CONFIG_X86_TSC
>> + /*
>> + * Xeon E5 BT81 errata: TSC is not affected by warm reset.
>> + * The TSC registers for CPUs other than CPU0 are not cleared by a warm
>> + * reset resulting in a constant offset error.
>> + */
>> + if ((c->x86 == 6) && (c->x86_model == 0x3f))
>> + set_cpu_bug(c, X86_BUG_TSC_OFFSET);
>> +#endif
>
> That's hardly a family, that's just one, Haswell server.
How did you come up with that x86_model? The document you linked to
claimes that "Extended Model" is 0010b and "Model Number" is 1101b, so
the x86_model you are looking for should be 0x2d.
next prev parent reply other threads:[~2015-11-13 21:13 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-11-09 19:59 [RFC PATCH] tsc: synchronize TSCs on buggy Intel Xeon E5 CPUs with offset error gratian.crisan
2015-11-09 22:02 ` Peter Zijlstra
[not found] ` <CAKA=qzarnUUmZb7DQE+u0Dei3F+FQNoL2bak_-dV9D9+3L=itQ@mail.gmail.com>
2015-11-10 18:27 ` Josh Hunt
2015-11-10 19:47 ` Gratian Crisan
2015-11-10 20:41 ` Josh Hunt
2015-11-11 15:41 ` Gratian Crisan
2015-11-13 20:43 ` Peter Zijlstra
2015-11-17 16:38 ` Gratian Crisan
2015-11-19 19:04 ` Gratian Crisan
2015-11-13 21:13 ` Dave Hansen [this message]
2015-11-17 16:49 ` Gratian Crisan
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=56465279.2010502@intel.com \
--to=dave.hansen@intel.com \
--cc=bp@alien8.de \
--cc=gratian.crisan@ni.com \
--cc=gratian@gmail.com \
--cc=hpa@zytor.com \
--cc=joshc@ni.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.