From: KY Srinivasan <kys@microsoft.com>
To: Jan Beulich <JBeulich@suse.com>
Cc: "olaf@aepfle.de" <olaf@aepfle.de>, "bp@alien8.de" <bp@alien8.de>,
"apw@canonical.com" <apw@canonical.com>,
"x86@kernel.org" <x86@kernel.org>,
"tglx@linutronix.de" <tglx@linutronix.de>,
"devel@linuxdriverproject.org" <devel@linuxdriverproject.org>,
"gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>,
"jasowang@redhat.com" <jasowang@redhat.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"hpa@zytor.com" <hpa@zytor.com>
Subject: RE: [PATCH 2/3] X86: Add a check to catch Xen emulation of Hyper-V
Date: Thu, 31 Jan 2013 14:46:24 +0000 [thread overview]
Message-ID: <32e50a43db8849f2944db256989bebb8@SN2PR03MB061.namprd03.prod.outlook.com> (raw)
In-Reply-To: <510A2D5802000078000BAEAA@nat28.tlf.novell.com>
> -----Original Message-----
> From: Jan Beulich [mailto:JBeulich@suse.com]
> Sent: Thursday, January 31, 2013 2:38 AM
> To: KY Srinivasan
> Cc: olaf@aepfle.de; bp@alien8.de; apw@canonical.com; x86@kernel.org;
> tglx@linutronix.de; devel@linuxdriverproject.org; gregkh@linuxfoundation.org;
> jasowang@redhat.com; linux-kernel@vger.kernel.org; hpa@zytor.com
> Subject: RE: [PATCH 2/3] X86: Add a check to catch Xen emulation of Hyper-V
>
> >>> On 30.01.13 at 19:12, KY Srinivasan <kys@microsoft.com> wrote:
> > Presumably, Hyper-V emulation is only to run enlightened Windows. The issue
> > with
> > Xen is not that it emulates Hyper-V, but this emulation is turned on while
> > running Linux.
> > That is the reason I chose to check for Xen. Would you prefer a DMI check
> > for the Hyper-V
> > platform.
>
> I consider DMI checks to be too fragile here - in particular with
> the eventual passing through of host DMI attributes to guests,
> this sets you up for mistakes. Instead, I would envision you
> scanning the whole CPUID range "reserved" for virtualization
> (starting at 0x40000000) and see whether you get back
> anything other than the Hyper-V identification (much like the
> way xen_cpuid_base() scans for the Xen range). Of course
> that's under the premise that you're right in assuming Hyper-V
> would never emulate any other hypervisor's interface.
Agreed; I will make the appropriate changes as you have recommended.
Regards,
K. Y
next prev parent reply other threads:[~2013-01-31 14:47 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-30 0:51 [PATCH 0/3] X86: Deliver Hyper-V interrupts on a seperate IDT vector K. Y. Srinivasan
2013-01-30 0:51 ` [PATCH 1/3] x86: Hyper-V: register clocksource only if its advertised K. Y. Srinivasan
2013-01-30 0:51 ` [PATCH 2/3] X86: Add a check to catch Xen emulation of Hyper-V K. Y. Srinivasan
2013-01-30 8:53 ` Jan Beulich
2013-01-30 18:12 ` KY Srinivasan
2013-01-30 18:19 ` H. Peter Anvin
2013-01-31 7:37 ` Jan Beulich
2013-01-31 14:46 ` KY Srinivasan [this message]
2013-01-31 15:53 ` KY Srinivasan
2013-01-31 16:45 ` Jan Beulich
2013-01-31 18:29 ` H. Peter Anvin
2013-01-31 21:41 ` H. Peter Anvin
2013-02-01 13:19 ` Stefano Stabellini
2013-02-01 15:10 ` KY Srinivasan
2013-02-01 19:34 ` KY Srinivasan
2013-01-30 0:51 ` [PATCH 3/3] X86: Handle Hyper-V vmbus interrupts as special hypervisor interrupts K. Y. Srinivasan
2013-01-30 8:58 ` Jan Beulich
2013-01-31 14:55 ` KY Srinivasan
2013-02-04 1:21 [PATCH 0/3] X86: Deliver Hyper-V interrupts on a seperate IDT vector K. Y. Srinivasan
2013-02-04 1:22 ` [PATCH 1/3] x86: Hyper-V: register clocksource only if its advertised K. Y. Srinivasan
2013-02-04 1:22 ` [PATCH 2/3] X86: Add a check to catch Xen emulation of Hyper-V K. Y. Srinivasan
2013-04-17 7:06 ` Michael S. Tsirkin
2013-04-17 13:20 ` KY Srinivasan
2013-04-17 12:48 ` Michael S. Tsirkin
2013-04-17 14:12 ` KY Srinivasan
2013-04-17 13:25 ` Michael S. Tsirkin
2013-04-17 14:34 ` KY Srinivasan
2013-04-17 13:48 ` Michael S. Tsirkin
2013-04-17 15:31 ` KY Srinivasan
2013-04-17 15:50 ` Jan Beulich
2013-04-17 16:28 ` KY Srinivasan
2013-04-18 7:48 ` Michael S. Tsirkin
2013-04-18 13:23 ` KY Srinivasan
2013-04-18 13:30 ` KY Srinivasan
2013-04-17 13:52 ` Jan Beulich
2013-04-17 13:01 ` Michael S. Tsirkin
2013-04-17 13:11 ` Michael S. Tsirkin
2013-04-17 14:09 ` Jan Beulich
2013-04-17 15:17 ` H. Peter Anvin
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