XSA-273 involves one hyperthread being able to use Spectre-like
techniques to "spy" on another thread. The details are somewhat
complicated, but the upshot is that after all Xen-based mitigations
have been applied:
* PV guests cannot spy on sibling threads
* HVM guests can spy on sibling threads
(NB that for purposes of this vulnerability, PVH and HVM guests are
identical. Whenever this comment refers to 'HVM', this includes PVH.)
There are many possible mitigations to this, including disabling
hyperthreading entirely. But another solution would be:
* Specify some cores as PV-only, others as PV or HVM
* Allow HVM guests to only run on thread 0 of the "HVM-or-PV" cores
* Allow PV guests to run on the above cores, as well as any thread of the PV-only cores.
For example, suppose you had 16 threads across 8 cores (0-7). You
could specify 0-3 as PV-only, and 4-7 as HVM-or-PV. Then you'd set
the affinity of the HVM guests as follows (binary representation):
0000000010101010
And the affinity of the PV guests as follows:
1111111110101010
In order to make this easy, this patches introduces three "global affinity
masks", placed in xl.conf:
vm.cpumask
vm.hvm.cpumask
vm.pv.cpumask
These are parsed just like the 'cpus' and 'cpus_soft' options in the
per-domain xl configuration files. The resulting mask is AND-ed with
whatever mask results at the end of the xl configuration file.
`vm.cpumask` would be applied to all guest types, `vm.hvm.cpumask`
would be applied to HVM and PVH guest types, and `vm.pv.cpumask`
would be applied to PV guest types.
The idea would be that to implement the above mask across all your
VMs, you'd simply add the following two lines to the configuration
file:
vm.hvm.cpumask=8,10,12,14
vm.pv.cpumask=0-8,10,12,14
See xl.conf manpage for details.
This is part of XSA-273 / CVE-2018-3646.
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Make it possible to get and set a (Credit1) scheduler's
vCPU migration delay via the SCHEDOP sysctl, from both
libxl and xl (no change needed in libxc).
Signed-off-by: Dario Faggioli <dfaggioli@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
This patch implements new generic set value interfaces in libxc and libxl.
These interfaces are suitable for all allocation features. It also adds a
new MBA set value command in xl.
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
This patch implements generic get value interfaces in libxc and libxl.
It also refactors the get value flow in xl to make it be suitable for all
allocation features. Based on that, a new MBA get value command is added in xl.
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
This patch implements a new xl get HW info interface. A new argument
is added for psr-hwinfo command to get and show MBA HW info.
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
An option is provided in libxl to enable/disable SBSA vuart while
creating a guest domain.
Libxl now supports a generic vuart console and SBSA uart is a specific type.
In future support can be added for multiple vuart of different types.
User can enable SBSA vuart by adding the following line in the guest
configuration file:
vuart = "sbsa_uart"
Signed-off-by: Bhupinder Thakur <bhupinder.thakur@linaro.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
The libxl interfaces and related functions are not necessary to be included by
'LIBXL_HAVE_PSR_CMT' and 'LIBXL_HAVE_PSR_CAT'. So replace them to common x86
macros. Furthermore, only compile 'xl_psr.c' under x86.
Suggested-by: Roger Pau Monné <roger.pau@citrix.com>
Suggested-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Add a new xl command "set-parameters" to set hypervisor parameters at
runtime similar to boot time parameters via command line.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
This patch implements the xl/xc changes to support set CBM
for L2 CAT.
The new level option is introduced to original CAT setting
command in order to set CBM for specified level CAT.
- 'xl psr-cat-set' is updated to set cache capacity bitmasks(CBM)
for a domain according to input cache level.
root@:~$ xl psr-cat-set -l2 1 0x7f
root@:~$ xl psr-cat-show -l2 1
Socket ID : 0
Default CBM : 0xff
ID NAME CBM
1 ubuntu14 0x7f
Signed-off-by: He Chen <he.chen@linux.intel.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
This patch implements changes in xl/xc changes to support
showing CBM of L2 CAT.
The new level option is introduced to original CAT showing
command in order to show CBM for specified level CAT.
- 'xl psr-cat-show' is updated to show CBM of a domain
according to input cache level.
Examples:
root@:~$ xl psr-cat-show -l2 1
Socket ID : 0
Default CBM : 0xff
ID NAME CBM
1 ubuntu14 0x7f
Signed-off-by: He Chen <he.chen@linux.intel.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
The hypervisor code (tmemc_shared_pool_auth) since the inception
would consider auth values of:
0 - to disable authentication!
1 - to enable authentication for the given UUID.
The docs have it the other way around, so lets fix it.
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
They should be treated like any other libraries installed on the build
host. Compiler options are set correctly to point to their locations.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
It makes clear distinction between the client (xl) and library (libxl),
which should help design better APIs. This will also help reduce the
code size in libxl directory.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Wei Liu
Oleksandr Grytsov
Dario Faggioli
Yi Sun
Meng Xu
Bhupinder Thakur
Dario Faggioli
Juergen Gross
Konrad Rzeszutek Wilk
Zhang Chen