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t=1639500838; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=QtNv/7h+fciRTz7jjI8Peww8Cq4yeg48ZoFD9a2qxew=; b=O1WAbcU/er4Cz8Me5F+K2XGRxjIBCw9QQeEuc597eQv9zUkuRLdu6ZxF7kXKcVS74E2tiH nsty3JeeBPTkCuaUX3vMZuyDCq5siCL4CBm0NoHiqGFnoJADDwR6MQwVsaRBl+2sulwhDs tsBA0rzNHG/6jgWVRHEZyyBp7fnqKMM= X-MC-Unique: ud9fYWjMOMK-dcTE7FUafA-1 From: Tim Wiederhake To: libvir-list@redhat.com Subject: [libvirt PATCH 1/2] docs: domain: Clarify on the dangers of migrating with hyperv-passthrough enabled Date: Tue, 14 Dec 2021 17:53:42 +0100 Message-Id: <20211214165343.57954-2-twiederh@redhat.com> In-Reply-To: <20211214165343.57954-1-twiederh@redhat.com> References: <20211214165343.57954-1-twiederh@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-loop: libvir-list@redhat.com Cc: Tim Wiederhake X-BeenThere: libvir-list@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: Development discussions about the libvirt library & tools List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: libvir-list-bounces@redhat.com Errors-To: libvir-list-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=libvir-list-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1639500840488100001 Content-Type: text/plain; charset="utf-8" Signed-off-by: Tim Wiederhake Reviewed-by: Michal Privoznik --- docs/formatdomain.rst | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst index 0c5e33c78f..2e9c450606 100644 --- a/docs/formatdomain.rst +++ b/docs/formatdomain.rst @@ -1929,7 +1929,14 @@ are: Set exactly the specified features. =20 ``passthrough`` - Enable all features currently supported by the hypervisor. + Enable all features currently supported by the hypervisor, even thos= e that + libvirt does not understand. Migration of a guest using passthrough = is + dangerous if the source and destination hosts are not identical in b= oth + hardware, QEMU version, microcode version and configuration. If such= a + migration is attempted then the guest may hang or crash upon resuming + execution on the destination host. Depending on hypervisor version t= he + virtual CPU may or may not contain features which may block migration + even to an identical host. =20 The ``mode`` attribute can be omitted and will default to ``custom``. =20 --=20 2.31.1