From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56023) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dTaHr-0005uv-UO for qemu-devel@nongnu.org; Fri, 07 Jul 2017 16:55:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dTaHn-000213-6d for qemu-devel@nongnu.org; Fri, 07 Jul 2017 16:55:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47704) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dTaHm-00020K-TG for qemu-devel@nongnu.org; Fri, 07 Jul 2017 16:55:35 -0400 References: From: Eric Blake Message-ID: <346b5b87-4d9b-ab82-8966-71680ae06af0@redhat.com> Date: Fri, 7 Jul 2017 15:55:31 -0500 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="rri3x1Q9WDiAxuhlMMg1i9kPsFWjBSCQu" Subject: Re: [Qemu-devel] [RFC 0/3] qemu-ga: support for sending events List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?B?VG9tw6HFoSBHb2xlbWJpb3Zza8O9?= , Michael Roth Cc: qemu-devel@nongnu.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --rri3x1Q9WDiAxuhlMMg1i9kPsFWjBSCQu From: Eric Blake To: =?UTF-8?B?VG9tw6HFoSBHb2xlbWJpb3Zza8O9?= , Michael Roth Cc: qemu-devel@nongnu.org Message-ID: <346b5b87-4d9b-ab82-8966-71680ae06af0@redhat.com> Subject: Re: [Qemu-devel] [RFC 0/3] qemu-ga: support for sending events References: In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 06/23/2017 08:02 AM, Tom=C3=A1=C5=A1 Golembiovsk=C3=BD wrote: > This is just a draft, or a request for comments if you will. >=20 > This patch sets drafts the support of sending events by QEMU Guest Agen= t. > Events can plan important role in monitoring of the guest OS behaviour.= The > range of use cases ranges from events important for scheduling, e.g. me= mory and > CPU usage statistics, to things like changes to IP addresses on network= > interfaces to for example changes in the list of active users. >=20 > For now the patch set adds single periodic callback function to the GA = main > loop that can perform checks and trigger events that have occured since= > previous run of the callback. How do we guarantee that the guest cannot flood qemu with too many events= ? Obviously, qga is already used where we (in general) trust the guest to not be malicious, but we still have to assume that a guest can be compromised, and will try to abuse qga to escape to an attack against qem= u. >=20 > We can of course take it one step further and add a general framwork fo= r > periodically running any of the already implemented commands. Add a fun= ction > that would maintain a list of registered checks. Client would use some = command > (register-monitor-command) passing it a command name and timeout in sec= onds and > the monitoring handler would then run the specified command and report = the > result... or report only if the return value changed since previous inv= ocation. > This feature would remove part of the communication overhead between cl= ient and > GA. >=20 > So before I invest any more time in either of these approaches, tell me= =2E Would > somethign like this be wanted or is that too controversial? Any other t= houghts > and ideas? >=20 --=20 Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3266 Virtualization: qemu.org | libvirt.org --rri3x1Q9WDiAxuhlMMg1i9kPsFWjBSCQu Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJZX/VEAAoJEKeha0olJ0NqA50H/j0fIE3j3O8GZaIKYelGinQe VtlShvjyUpZ9XpKy6Q/uMUCND/+xmTTk+twm07QLxhFfayfqb97HlesWgKvJeT+S nXapD6HpyaX8CTaIO1MqF9IhGiQVWYWW9aWwHU+VtGtPqmOn6sVaNouJTbUVMVqU ujRe1dt9g55wgZGNlm1Xn+d0Syr1xvtsOsfne45ufoYRH9K9fcHKLSNSJfBSXLsh qN3XLRTIk3fUy9k2hq1gUbkBYLQqlF+NAmkFfujrWHQsWK5zXpfUnJu4eRpJT3AT 850dp/uu3szFH7uyruKKqHWk9ifSUibTylU+aQzGa5zimPvxWsNfWrxlebMfgac= =togJ -----END PGP SIGNATURE----- --rri3x1Q9WDiAxuhlMMg1i9kPsFWjBSCQu--