RFC 791 sets the minimum acceptable mtu to 68:
Every internet module must be able to forward a datagram of 68
octets without further fragmentation. This is because an internet
header may be up to 60 octets, and the minimum fragment is 8 octets.
In the Linux kernel source:
include/net/ip.h:#define IPV4_MIN_MTU 68 /* RFC 791 */
While there is no reason to expect a value <68 to be read from xenstore or
from the bridge make the value test require a number >= this minimum.
Signed-off-by: James Dingwall <james@dingwall.me.uk>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
The set_mtu() function of xen-network-common.sh currently has this code:
if [ ${type_if} = vif ]
then
local dev_=${dev#vif}
local domid=${dev_%.*}
local devid=${dev_#*.}
local FRONTEND_PATH="/local/domain/$domid/device/vif/$devid"
xenstore_write "$FRONTEND_PATH/mtu" ${mtu}
fi
This works fine if the device has its default name but if the xen config
defines the vifname parameter the FRONTEND_PATH is incorrectly constructed.
Learn the frontend path by reading the appropriate value from the backend.
Also change use of `...` to $(...) for a consistent style in the script.
Signed-off-by: James Dingwall <james@dingwall.me.uk>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
The stimer enlightment was removed from the defaults list in commit
e83077a3d1 ("libxl: don't enable synthetic timers by default") but the
corresponding docs change was not made. Removing from docs as enabling the
enlightenment will hang Windows 10 guests.
Fixes: e83077a3d1 ("libxl: don't enable synthetic timers by default")
Signed-off-by: James Dingwall <james@dingwall.me.uk>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-Acked-By: Oleksii Kurochko <oleksii.kurochko@gmail.com>
The corresponding code in the Xen qemu repository was not applied from
qemu-xen-4.18.0.
Signed-off-by: James Dingwall <james@dingwall.me.uk>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
James Dingwall