From: "H. Peter Anvin" <hpa@zytor.com>
To: Andy Lutomirski <luto@kernel.org>, Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>,
Gu Zheng <guz.fnst@cn.fujitsu.com>,
Thomas Gleixner <tglx@linutronix.de>,
linux-kernel@vger.kernel.org, x86@kernel.org
Subject: Re: [RFC PATCH] x86, espfix: use spin_lock rather than mutex
Date: Tue, 19 May 2015 08:04:37 -0700 [thread overview]
Message-ID: <555B5105.4040808@zytor.com> (raw)
In-Reply-To: <555A40C9.6010605@kernel.org>
On 05/18/2015 12:43 PM, Andy Lutomirski wrote:
> On 05/15/2015 12:27 AM, H. Peter Anvin wrote:
>> On 05/14/2015 11:54 PM, Ingo Molnar wrote:
>>>
>>> The only slightly subtle detail with that is to use alloc_pages_node()
>>> with the secondary CPU's node, to make sure the espfix stack is
>>> NUMA-local to the CPU that is going to use it.
>>>
>>
>> It doesn't hurt, although it isn't super critical as each page will be
>> shared among 64 CPUs. The whole espfix stack is only a single cacheline
>> long.
>>
>
> I don't think we actually need these pages allocated until we try to run
> user code. Can we move this very late in initialization instead?
>
Yes, we could, as long as it is run on each CPU before that CPU tries to
run user code.
-hpa
next prev parent reply other threads:[~2015-05-19 15:05 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-14 11:37 [RFC PATCH] x86, espfix: use spin_lock rather than mutex Gu Zheng
2015-05-14 12:26 ` Borislav Petkov
2015-05-14 18:29 ` Ingo Molnar
2015-05-14 21:27 ` Borislav Petkov
2015-05-14 22:13 ` H. Peter Anvin
2015-05-15 6:54 ` Ingo Molnar
2015-05-15 7:27 ` H. Peter Anvin
2015-05-18 19:43 ` Andy Lutomirski
2015-05-19 15:04 ` H. Peter Anvin [this message]
2015-05-22 10:13 ` [RFC PATCH] x86, espfix: postpone the initialization of espfix stack for AP Gu Zheng
2015-05-28 1:20 ` Gu Zheng
2015-05-29 1:07 ` Andy Lutomirski
2015-05-29 0:57 ` Gu Zheng
2015-06-02 9:23 ` Gu Zheng
2015-06-02 9:25 ` [RFC PATCH V2] " Gu Zheng
2015-06-02 11:59 ` Ingo Molnar
2015-06-03 9:58 ` Gu Zheng
2015-06-04 9:45 ` [PATCH V1] " Gu Zheng
2015-06-17 5:53 ` Zhu Guihua
2015-06-17 7:27 ` H. Peter Anvin
2015-06-17 21:04 ` Borislav Petkov
2015-06-17 21:11 ` H. Peter Anvin
2015-06-17 21:50 ` Borislav Petkov
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=555B5105.4040808@zytor.com \
--to=hpa@zytor.com \
--cc=bp@alien8.de \
--cc=guz.fnst@cn.fujitsu.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mingo@kernel.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.