From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:55513) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TDfkJ-0003zV-Ij for qemu-devel@nongnu.org; Mon, 17 Sep 2012 14:08:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TDfkI-00018A-Ei for qemu-devel@nongnu.org; Mon, 17 Sep 2012 14:08:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49415) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TDfkI-00017q-47 for qemu-devel@nongnu.org; Mon, 17 Sep 2012 14:08:34 -0400 Message-ID: <5057671C.40400@redhat.com> Date: Mon, 17 Sep 2012 12:08:28 -0600 From: Eric Blake MIME-Version: 1.0 References: <20120917145622.5ba28e23@doriath.home> In-Reply-To: <20120917145622.5ba28e23@doriath.home> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------enigFA785F2A0326D63AEEFEB6B3" Subject: Re: [Qemu-devel] qmp: dump-guest-memory: -p option has issues, fix it or drop it? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Luiz Capitulino Cc: Marcelo Tosatti , Markus Armbruster , qemu-devel This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigFA785F2A0326D63AEEFEB6B3 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 09/17/2012 11:56 AM, Luiz Capitulino wrote: > Hi Wen, >=20 > We've re-reviewed the dump-guest-memory command and found some > possible issues with the -p option. >=20 > However, I also think that we should consider if having the -p > feature is really worth it. It's a complex feature and has a number > of limitations*. If libvirt doesn't use this, dropping it shouldn't > be a big deal (we can return an error when -p is used). >=20 > * The issues discussed in this email plus the fact that the guest > memory may be corrupted, and the guest may be in real-mode even > when paging is enabled Libvirt is not currently exposing the -p mode (that is, it currently blindly passes 'paging':false to the JSON command). Dropping it would have no noticeable impact to libvirt. (Note - libvirt _did_ wire up an internal flag to qemu_monitor_json.c, QEMU_MONITOR_DUMP_PAGING, but nothing sets this flag, so libvirt would need a cleanup patch to remove it as useless code, but that is not user-visible.) --=20 Eric Blake eblake@redhat.com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --------------enigFA785F2A0326D63AEEFEB6B3 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Mozilla - http://www.enigmail.net/ iQEcBAEBCAAGBQJQV2ceAAoJEKeha0olJ0NqcjYIAJIHBPAaciF9TQLae4EjbCDh V2vgz+/wqtDl+rKySXy0S/I4TzR8ja8wfYbFhZowJwfIhD4PAEEIW6A8xZqJxazZ pVMRopqw/x7dpe3F2nIqH6q8H5pT131ffbVw92a4QUqArRbi7hbiNmxq9ytDqEXr b9aJOVO0Y/kpBERBYClupvudZqMwor7lNfeMbY8/V7f5U+nxZu79AvF9Tu8Tut4f pu19I+2tCajjGDVUCuC8fdkxwOwzL4jaVGmW9kCdAf8YGbz6HmnbUgfC1PfXAAoS MyVgzk69xTCKUy1soIuTaXxH9cW+gnVudDqJAFo+NKPyNHh9vtl45pn65sCmvXc= =TDtu -----END PGP SIGNATURE----- --------------enigFA785F2A0326D63AEEFEB6B3--