Expose VIRT_SSBD to guests if the hardware supports setting SSBD in
the LS_CFG MSR (a.k.a. non-architectural way). Different AMD CPU
families use different bits in LS_CFG, so exposing VIRT_SPEC_CTRL.SSBD
allows for an unified way of exposing SSBD support to guests on AMD
hardware that's compatible migration wise, regardless of what
underlying mechanism is used to set SSBD.
Note that on AMD Family 17h and Hygon Family 18h processors the value
of SSBD in LS_CFG is shared between threads on the same core, so
there's extra logic in order to synchronize the value and have SSBD
set as long as one of the threads in the core requires it to be set.
Such logic also requires extra storage for each thread state, which is
allocated at initialization time.
Do the context switching of the SSBD selection in LS_CFG between
hypervisor and guest in the same handler that's already used to switch
the value of VIRT_SPEC_CTRL.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Henry Wang <Henry.Wang@arm.com>
Re-commited with a tag removed.
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
A person tagged in commit 646589ac14
claims the tag is in accurate; revert this commit so that we can
re-commit it again with the tag corrected.
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Expose VIRT_SSBD to guests if the hardware supports setting SSBD in
the LS_CFG MSR (a.k.a. non-architectural way). Different AMD CPU
families use different bits in LS_CFG, so exposing VIRT_SPEC_CTRL.SSBD
allows for an unified way of exposing SSBD support to guests on AMD
hardware that's compatible migration wise, regardless of what
underlying mechanism is used to set SSBD.
Note that on AMD Family 17h and Hygon Family 18h processors the value
of SSBD in LS_CFG is shared between threads on the same core, so
there's extra logic in order to synchronize the value and have SSBD
set as long as one of the threads in the core requires it to be set.
Such logic also requires extra storage for each thread state, which is
allocated at initialization time.
Do the context switching of the SSBD selection in LS_CFG between
hypervisor and guest in the same handler that's already used to switch
the value of VIRT_SPEC_CTRL.
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Henry Wang <Henry.Wang@arm.com>
GrUB2 can be told to leave the screen in the graphics mode it has been
using (or any other one), via "set gfxpayload=keep" (or suitable
variants thereof). In this case we can avoid doing another mode switch
ourselves. This in particular avoids possibly setting the screen to a
less desirable mode: On one of my test systems the set of modes
reported available by the VESA BIOS depends on whether the interposed
KVM switch has that machine set as the active one. If it's not active,
only modes up to 1024x768 get reported, while when active 1280x1024
modes are also included. For things to always work with an explicitly
specified mode (via the "vga=" option), that mode therefore needs be a
1024x768 one.
For some reason this only works for me with "multiboot2" (and
"module2"); "multiboot" (and "module") still forces the screen into text
mode, despite my reading of the sources suggesting otherwise.
For starters I'm limiting this to graphics modes; I do think this ought
to also work for text modes, but
- I can't tell whether GrUB2 can set any text mode other than 80x25
(I've only found plain "text" to be valid as a "gfxpayload" setting),
- I'm uncertain whether supporting that is worth it, since I'm uncertain
how many people would be running their systems/screens in text mode,
- I'd like to limit the amount of code added to the realmode trampoline.
For starters I'm also limiting mode information retrieval to raw BIOS
accesses. This will allow things to work (in principle) also with other
boot environments where a graphics mode can be left in place. The
downside is that this then still is dependent upon switching back to
real mode, so retrieving the needed information from multiboot info is
likely going to be desirable down the road.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Henry Wang <Henry.Wang@arm.com>
If we get mode dimensions wrong, having the remapping size controllable
via command line option isn't going to help much. Drop the option.
While adjusting this also
- add __initdata to the variable,
- use ROUNDUP() instead of open-coding it.
Requested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Now that we use ioremap_wc() for mapping the frame buffer, there's no
need for this option anymore. As noted in the change introducing the
use of ioremap_wc(), mtrr_add() didn't work in certain cases anyway.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
I have just forward-ported the CHANGELOG.md updates from the
stable-4.16 branch. But we need a new section for work in this
release cycle.
Signed-off-by: Ian Jackson <iwj@xenproject.org>
Document some of the relevant changes during the 4.16 release cycle.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
(cherry picked from commit e2544a28be)
Using qemu-traditional as device model is deprecated for some time now.
So change the default for building it to "disable". This will affect
ioemu-stubdom, too, as there is a direct dependency between the two.
Today it is possible to use a PVH/HVM Linux-based stubdom as device
model. Additionally using ioemu-stubdom isn't really helping for
security, as it requires to run a very old and potentially buggy qemu
version in a PV domain. This is adding probably more security problems
than it is removing by using a stubdom.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Acked-by: Ian Jackson <iwj@xenproject.org>
Release-acked-by: Ian Jackson <iwj@xenproject.org>
Using qemu-traditional as device model is deprecated for some time now.
So change the default for building it to "disable". This will affect
ioemu-stubdom, too, as there is a direct dependency between the two.
Today it is possible to use a PVH/HVM Linux-based stubdom as device
model. Additionally using ioemu-stubdom isn't really helping for
security, as it requires to run a very old and potentially buggy qemu
version in a PV domain. This is adding probably more security problems
than it is removing by using a stubdom.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Acked-by: Ian Jackson <iwj@xenproject.org>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
The stubdom based pv-grub is using a very outdated version of grub
(0.97) and should not be used any longer. Mainline grub has support for
PV guests for a long time now, so that should be used as a boot loader
of a PV domain.
So disable building pv-grub per default. In case someone really wants
to continue using it he/she can still use a pv-grub binary from an older
Xen version or manually enable building it via:
configure --enable-pv-grub
[ This was already disabled in osstest by 8dee6e333622
"make-flight: Drop pvgrub (pvgrub1) tests" -iwj ]
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Acked-by: Ian Jackson <iwj@xenproject.org>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
This amends commit 980d6acf15 ("IOMMU: make DMA containment of
quarantined devices optional").
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
The sysconfig variable XENSTORED_ROOTDIR is not used anymore.
It used to point to a directory with tdb files, which is now a tmpfs.
In case the database is not in tmpfs, like on sysv and BSD systems,
xenstored will truncate existing database files during start.
Fixes: 2ef6ace428 ("tools: don't remove tdb data base file before starting xenstored")
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wl@xen.org>
The change to deny all accesses to MSRs indexes not explicitly handled
prevents leaking unwanted data into guests.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
And update the release technician checklist to mention to edit it.
Signed-off-by: Ian Jackson <iwj@xenproject.org>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
Add entries for the relevant changes I've been working on during the
4.14 development time frame. Mostly performance improvements related
to pvshim scalability issues when running with high number of vCPUs.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Paul Durrant <paul@xen.org>
Andrew Cooper