Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled

From	"H. Peter Anvin" <hpa@zytor.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled
Date	2015-09-29 20:30 +0200
Message-ID	<qe7P4-5Ze-9@gated-at.bofh.it> (permalink)
References	(4 earlier) <qdG2u-5Zh-21@gated-at.bofh.it> <qdZ58-1ZA-13@gated-at.bofh.it> <qe72H-4PH-19@gated-at.bofh.it> <qe7P3-5Ze-5@gated-at.bofh.it> <qe7P4-5Ze-7@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

Ugh.  Didn't realize that.

On September 29, 2015 11:22:04 AM PDT, Andy Lutomirski <luto@amacapital.net> wrote:
>On Tue, Sep 29, 2015 at 11:18 AM, H. Peter Anvin <hpa@zytor.com> wrote:
>> SGDT would be easy to use, and it is logical that it is faster since
>it reads an internal register.  SIDT does too but unlike the GDT has a
>secondary limit (it can never be larger than 4096 bytes) and so all
>limits in the range 4095-65535 are exactly equivalent.
>>
>
>Using the IDT limit would have been a great ideal if Intel hadn't
>decided to clobber it on every VM exit.
>
>--Andy

-- 
Sent from my Android device with K-9 Mail. Please excuse my brevity.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Thread

[PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled Denys Vlasenko <dvlasenk@redhat.com> - 2015-09-26 20:10 +0200
  Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled "H. Peter Anvin" <hpa@zytor.com> - 2015-09-26 22:00 +0200
    Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled Denys Vlasenko <dvlasenk@redhat.com> - 2015-09-26 22:40 +0200
      Re: [PATCH] x86: Use entire page for the per-cpu GDT only if  paravirt-enabled Ingo Molnar <mingo@kernel.org> - 2015-09-28 10:00 +0200
        Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled Denys Vlasenko <dvlasenk@redhat.com> - 2015-09-28 14:50 +0200
          Re: [PATCH] x86: Use entire page for the per-cpu GDT only if  paravirt-enabled Ingo Molnar <mingo@kernel.org> - 2015-09-29 11:10 +0200
            Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled Andy Lutomirski <luto@amacapital.net> - 2015-09-29 19:40 +0200
              Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled Linus Torvalds <torvalds@linux-foundation.org> - 2015-09-29 20:00 +0200
                Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled Andy Lutomirski <luto@amacapital.net> - 2015-09-29 20:10 +0200
                Re: [PATCH] x86: Use entire page for the per-cpu GDT only if  paravirt-enabled "H. Peter Anvin" <hpa@zytor.com> - 2015-09-29 22:40 +0200
                Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled ebiederm@xmission.com (Eric W. Biederman) - 2015-09-30 03:30 +0200
                Re: [PATCH] x86: Use entire page for the per-cpu GDT only if  paravirt-enabled "H. Peter Anvin" <hpa@zytor.com> - 2015-09-30 03:40 +0200
                Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled ebiederm@xmission.com (Eric W. Biederman) - 2015-09-30 04:20 +0200
                Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled "H. Peter Anvin" <hpa@zytor.com> - 2015-09-30 04:30 +0200
              Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled "H. Peter Anvin" <hpa@zytor.com> - 2015-09-29 20:30 +0200
                Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled "H. Peter Anvin" <hpa@zytor.com> - 2015-09-29 20:30 +0200
                Re: [PATCH] x86: Use entire page for the per-cpu GDT only if paravirt-enabled Andy Lutomirski <luto@amacapital.net> - 2015-09-29 20:30 +0200

csiph-web