From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id EE49695435 for ; Fri, 12 Apr 2024 11:33:17 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id BE6F470CF for ; Fri, 12 Apr 2024 11:32:47 +0200 (CEST) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS for ; Fri, 12 Apr 2024 11:32:47 +0200 (CEST) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id C8AE2450DC for ; Fri, 12 Apr 2024 11:32:46 +0200 (CEST) Date: Fri, 12 Apr 2024 11:32:42 +0200 From: Fabian =?iso-8859-1?q?Gr=FCnbichler?= To: Proxmox VE development discussion References: <20240319150834.266548-1-h.duerr@proxmox.com> In-Reply-To: <20240319150834.266548-1-h.duerr@proxmox.com> MIME-Version: 1.0 User-Agent: astroid/0.16.0 (https://github.com/astroidmail/astroid) Message-Id: <1712914044.dmqqhkfhvy.astroid@yuna.none> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-SPAM-LEVEL: Spam detection results: 0 AWL 0.057 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record URIBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [qemu.pm, proxmox.com] Subject: Re: [pve-devel] [PATCH qemu-server 1/1] snapshot: prohibit snapshot with ram if vm has a passthrough pci device X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 12 Apr 2024 09:33:18 -0000 On March 19, 2024 4:08 pm, Hannes Duerr wrote: > When a snapshot is created with RAM, qemu attempts to save not only the > RAM content, but also the internal state of the PCI devices. >=20 > However, as not all drivers support this, this can lead to the device > drivers in the VM not being able to handle the saved state during the > restore/rollback and in conclusion the VM might crash. For this reason, > we now generally prohibit snapshots with RAM for VMs with passthrough > devices. >=20 > In the future, this prohibition can of course be relaxed for individual > drivers that we know support it, such as the vfio driver >=20 > Signed-off-by: Hannes Duerr > --- > PVE/API2/Qemu.pm | 10 ++++++++++ > 1 file changed, 10 insertions(+) >=20 > diff --git a/PVE/API2/Qemu.pm b/PVE/API2/Qemu.pm > index 40b6c30..0acd1c7 100644 > --- a/PVE/API2/Qemu.pm > +++ b/PVE/API2/Qemu.pm > @@ -5101,6 +5101,16 @@ __PACKAGE__->register_method({ > die "unable to use snapshot name 'pending' (reserved name)\n" > if lc($snapname) eq 'pending'; > =20 > + if ($param->{vmstate}) { > + my $conf =3D PVE::QemuConfig->load_config($vmid); > + > + for my $key (keys %$conf) { > + next if $key !~ /^hostpci\d+/; > + die "cannot snapshot VM with RAM due to passed-through PCI device(s), = which lack" > + ." the possibility to save/restore their internal state\n"; > + } > + } isn't the same also true of other local resources (e.g., passed-through USB?)? maybe we could find a way to unify the checks we do for live migration (PVE::QemuServer::check_local_resources), since that is almost the same code inside Qemu as a stateful snapshot+rollback? (not opposed to applying this before that happens though, just a question in general..) > + > my $realcmd =3D sub { > PVE::Cluster::log_msg('info', $authuser, "snapshot VM $vmid: $snapn= ame"); > PVE::QemuConfig->snapshot_create($vmid, $snapname, $param->{vmstate= }, > --=20 > 2.39.2 >=20 >=20 >=20 > _______________________________________________ > pve-devel mailing list > pve-devel@lists.proxmox.com > https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel >=20 >=20 >=20