From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joanna Rutkowska Subject: Re: S3 sleep in dom0 breaks dom0<->domU wallclock synchronization Date: Tue, 06 Jul 2010 11:10:56 +0200 Message-ID: <4C32F320.3060103@invisiblethingslab.com> References: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1605531969==" Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: Jeremy Fitzhardinge , "xen-devel@lists.xensource.com" , Jeremy Fitzhardinge , Rafal Wojtczuk , Konrad Rzeszutek Wilk List-Id: xen-devel@lists.xenproject.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --===============1605531969== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig05EB492B634A8E43C31A8E88" This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig05EB492B634A8E43C31A8E88 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 07/06/10 05:52, Keir Fraser wrote: > On 05/07/2010 23:50, "Jeremy Fitzhardinge" wrote: >=20 >>> BTW: wouldn't it be good to actually notify them? Consider e.g. DomU >>> that has some device assigned to it (say a NIC) -- if we emulated S3 >>> suspend/resume for this DomU, there is a hope it would properly >>> suspend/reinitialize the NIC, wouldn't it? >>> =20 >> >> I guess? That implies some kind of PV S3 suspend and resume event to >> feed into the dom U's device model. What does 2.6.18-xen do? >=20 > I don't think our S3 support is very compatible with PV device passthro= ugh. > We support HVM virtual S3, and can S3-sleep HVM guests across real host= S3, > but we don't have similar for PV guests. >=20 How about implementing something very simple, like a notification via xenstore (say, Dom0 would be setting some key)? Interested DomUs could then register a watch, and get notified when the system was resumed from S3. This would let them e.g. to call whatever hypercall is used normally on DomU boot to sync DomU wallclock, or reinitialize/reconnect the NIC. Obviously DomUs would not be notified when the system is just going to sleep, as this would require some more sophisticated protocol (I guess each DomU would have to ack within some given max timeout that it's done with preparing from sleep?). But perhaps we can just ignore it? Even if DomU has a NIC card assigned, wouldn't it be put to sleep by the southbridge anyway? So, seems like we only care about the resume event? joanna. --------------enig05EB492B634A8E43C31A8E88 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org/ iEYEARECAAYFAkwy8yEACgkQORdkotfEW87wOQCgu0SCv8ov4fmqsUiFd1TJcBtK w9kAoOauuIhMGytKQyutuCbcmOBDSltM =wAXw -----END PGP SIGNATURE----- --------------enig05EB492B634A8E43C31A8E88-- --===============1605531969== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel --===============1605531969==--