VMs created on older versions on Xen will not have been provisioned with
pages to support creation of non-default ioreq servers. In this case
the ioreq server API is not supported and QEMU's only option is to fall
back to using the default ioreq server pages as it did prior to
commit 3996e85c ("Xen: Use the ioreq-server API when available").
This patch therefore changes the code in xen_common.h to stop considering
a failure of xc_hvm_create_ioreq_server() as a hard failure but simply
as an indication that the guest is too old to support the ioreq server
API. Instead a boolean is set to cause reversion to old behaviour such
that the default ioreq server is then used.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
The ioreq-server API added to Xen 4.5 offers better security than
the existing Xen/QEMU interface because the shared pages that are
used to pass emulation request/results back and forth are removed
from the guest's memory space before any requests are serviced.
This prevents the guest from mapping these pages (they are in a
well known location) and attempting to attack QEMU by synthesizing
its own request structures. Hence, this patch modifies configure
to detect whether the API is available, and adds the necessary
code to use the API if it is.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
The Xen ioreq-server API, introduced in Xen 4.5, requires that PCI device
models explicitly register with Xen for config space accesses. This patch
adds a listener interface into qdev-core which can be used by the Xen
interface code to monitor for arrival and departure of PCI devices.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
The intention of the Xen PV device is that it is used as a parent
device for PV drivers in Xen HVM guests and the set of PV drivers that
bind to the device is determined by its device ID (and possibly
vendor ID and revision). As such, the device should not have a default
device ID, it should always be supplied by the Xen toolstack.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Introduces a new Xen PV PCI device which will act as a binding point for
PV drivers for Xen.
The device has parameterized vendor-id, device-id and revision to allow to
be configured as a binding point for any vendor's PV drivers.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Creation of the xen-platform device is currently hardcoded into machine
type pc's initialization code, guarded by a test for the whether the xen
accelerator is enabled. This patch moves the creation of xen-platform into
the initialization code of the xenfv machine type. This maintains backwards
compatibility for that machine type but allows more flexibility if another
machine type is used with Xen HVM domains.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Xen HVM domains normally spawn QEMU with a dedicated xenfv machine type. The
initialization code for this machine type can easily be pulled into the
generic pc initialization code and guarded with a test for whether the xen
accelerator options is specified, which is more consistent with the way
other accelerators are used.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Paul Durrant