xenstore-paths.markdown talked about ~/device/serial/, but that's not
used.
(It is very wrong for this value, which contains a driver domain
filesystem path, to be in the guest's area of xenstore. However, it
is only ever created by libxl and ready by xenconsoled. When it is
created, it inherits the read-only permissions of /local/domain/DOMID.
So there is no security bug.)
This is a followup to XSA-175.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
We want to stop libxl trustingly reading information from the backend
directory (since this is, of course, writeable by the backend, which
might be a semi-trusted driver domain).
In principle it is wrong in current libxl for anything to try to
divine virtual device configuration from xenstore: the JSON domain
config ought to supply that, and xenstore should only tell us which
devices actually exist.
However:
Firstly, there are several existing places where configuration
information is retrieved from xenstore rather than JSON. We do not
want to reen gineer this in a security patch.
Secondly, we want to make a security patch which can be backported to
versions of libxl without the JSON configuration machinery.
So we take the expedient approach of keeping a copy of the
configuration somewhere we trust, namely /libxl. This is obviously
fairly low-risk, although it does write significantly more keys in
xenstore.
In this patch we make this change in libxl__device_generic_add. This
is responsible for actually writing the vast majority of device
information to xenstore. There are a few loose ends which will be
dealt with in a moment.
Likewise, changes to readers to use the new location will appear in
further patches.
This is part of XSA-178.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
This gives us a record of all the backends we have set up for a
domain, which is separate from the frontends in
/local/domain/$DOMID/device.
In particular:
1. A guest has write permission for the frontend path:
/local/domain/$DOMID/device/$KIND/$DEVID
which means that the guest can completely delete the frontend.
(They can't recreate it because they don't have write permission
on the containing directory.)
2. A guest has write permission for the backend path recorded in the
frontend, ie, it can write to
/local/domain/$DOMID/device/$KIND/$DEVID/backend
which means that the guest can break the association between
frontend and backend.
So we can't rely on iterating over the frontends to find all the
backends, or examining a frontend to discover how a device is
configured.
So, have libxl__device_generic_add record the frontend and backend
paths in /libxl/$DOMID/device, and have libxl__device_destroy remove
them again.
Create the containing directory /libxl/GUEST/device in
libxl__domain_make. The already existing xs_rm in devices_destroy_cb
will take care of removing it.
This is part of XSA-175.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
We've been told by Intel that inconsistent cachability between
multiple mappings of the same page can affect system stability only
when the affected page is an MMIO one. Since the stale data issue is
of no relevance to the hypervisor (since all guest memory accesses go
through proper accessors and validation), handling of RAM pages
remains unchanged here. Any MMIO mapped by domains however needs to be
done consistently (all cachable mappings or all uncachable ones), in
order to avoid Machine Check exceptions. Since converting existing
cachable mappings to uncachable (at the time an uncachable mapping
gets established) would in the PV case require tracking all mappings,
allow MMIO to only get mapped uncachable (UC, UC-, or WC).
This also implies that in the PV case we mustn't use the L1 PTE update
fast path when cachability flags get altered.
Since in the HVM case at least for now we want to continue honoring
pinned cachability attributes for pages not mapped by the hypervisor,
special case handling of r/o MMIO pages (forcing UC) gets added there.
Arguably the counterpart change to p2m-pt.c may not be necessary, since
UC- (which already gets enforced there) is probably strict enough.
Note that the shadow code changes include fixing the write protection
of r/o MMIO ranges: shadow_l1e_remove_flags() and its siblings, other
than l1e_remove_flags() and alike, return the new PTE (and hence
ignoring their return values makes them no-ops).
This is CVE-2016-2270 / XSA-154.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: c61a6f74f8
master date: 2016-02-17 16:16:53 +0100
gnttab_max_frames incorrectly referred to numbers of grant tab
operations and gnttab_max_maptrack_frames was confusingly worded.
Add the default for gnttab_max_frames while here (it's currently the
same on all arches since no arch uses the available arch override) and
adjust the default for gnttab_max_maptrack_frames to match the normal
form.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: ef17887d84
master date: 2016-01-19 16:24:44 +0000
Introduce and enforce separate limits for ordinary DomU, DomU with
pass-through device(s), control domain, and hardware domain.
The DomU defaults were determined based on what so far was allowed by
multipage_allocation_permitted().
The x86 hwdom default was chosen based on linux-2.6.18-xen.hg c/s
1102:82782f1361a9 indicating 2Mb is not enough, plus some slack.
The ARM hwdom default was chosen to allow 2Mb (order-9) mappings, plus
a little bit of slack.
This is CVE-2015-8338 / XSA-158.
Reported-by: Julien Grall <julien.grall@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
master commit: 4a578b316e
master date: 2015-12-08 14:00:33 +0100
Since XSA-131 qemu-xen has defaulted to non-permissive mode and the
option was extended to cover that case in 015a373351 "tools: libxl:
allow permissive qemu-upstream pci passthrough".
Since I was rewrapping to adjust the text anyway I've split the safety
warning into a separate paragraph to make it more obvious.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Eric <epretorious@yahoo.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit 7f25baba1c)
Since commit 191b3f3344 ("p2m/ept: enable PML in p2m-ept for
log-dirty"), the A and D bits of EPT paging entries are set
unconditionally, regardless of whether PML is enabled or not. This
causes a regression in Xen 4.6 on some processors due to Intel Errata
AVR41 -- HVM guests get severe memory corruption when the A bit is set
due to incorrect TLB flushing on mov to cr3. The erratum affects the
Atom C2000 family (Avoton).
To fix, do not set the A bit on this processor family.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Move feature suppression to feature detection code. Add command line
override.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
master commit: 33b55dc103
master date: 2015-10-02 13:39:12 +0200
Section 'IGNORED FOR COMPATIBILITY WITH XM' separates 'CACHE MONITORING
TECHNOLOGY' and 'CACHE ALLOCATION TECHNOLOGY' but they really should be
put together.
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Reviewed-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit 61598449ae)
Drop the chapter number as it can be confusing when it gets changed in
the referred document.
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Reviewed-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
[ ijc -- dropped hunk changing URL to specific revision, this is not
needed now that the references do not include a specific
chapter number ]
(cherry picked from commit 7f732ffa2b)
This is because the migration stream does not preserve node information.
Note this is not a regression for migration v2 vs legacy migration
because neither of them preserves node information.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
[ ijc -- some grammar fixes to the doc and fixed a comment ]
(cherry picked from commit fa6b5490be)
c/s a430436 "docs: Support for generating man(8) pages" accidentally
failed to update to the install and clean rules for man8 pages, meaning
that c/s 7b21214 "docs: Move xentrace.8 to docs/man/xentrace.pod.8"
caused a packaging regression when it came to xentop.8
To avoid similar bugs in the future, move the generation of the build,
install and clean rules into the manpage metarule.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
And transform to POD to match our other manpages.
The content is identical, although the formatting was altered slightly
to conform to more usual manpage layout.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
The manpage rules are very repetative, because of the section number being
present in the filenames.
Instead of adding another set of 3 rules, switch to using a metarule to
automate the repetative action. New rules for different manpage sections can
be added simply by extending the $(foreach)
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
And transform to POD to match our other manpages.
The content is identical (other than one correction), although the
layout differs slightly with certain indentation.
As a correction, remove the reference to xentrace_cpusplit(1) which was
removed in c/s 9b9ca98b6a, more than 10 years ago!
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
And transform to POD to match our other manpages.
The content is identical, although the layout differs slightly with
certain indentation.
In addition, adjust the MAN{1,5}SRC-y `find` runes to be more general.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
When using Linux >= 3.19 (commit 47591df) as dom0 on some Intel Ironlake
devices, It is possible to encounter graphics issues that make screen
unreadable or crash the system. It was reported in freedesktop bugzilla:
https://bugs.freedesktop.org/show_bug.cgi?id=90037
As we still cannot find a proper fix for this problem, this patch adds
iommu=igfx option to control whether Intel graphics IOMMU is enabled.
Running Xen with iommu=no-igfx is similar to running Linux with
intel_iommu=igfx_off, which disables IOMMU for Intel GPU. This can be
used by users to manually workaround the problem before a fix is
available for i915 driver.
Signed-off-by: Ting-Wei Lan <lantw44@gmail.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
The legacy "toolstack" record as implemented in libxl turns out not to
be 32/64bit safe. As migration v2 has not shipped yet, take this
opportunity to adjust the specification and fix the incompatibility.
Libxl shall loose all knowledge of the old "toolstack" blob and use this
EMULATOR_XENSTORE_DATA record instead. Compatibility shall be handled
by the legacy conversion script.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Add further instructions to the libxc "Future Extensions" section, and
provide such a section for libxl.
In addition, drop the "In experimental __func__" IPRINTF()s from the
libxc implementations.
Finally, a correction to libxl's "Not Yet Included" section which
should have been amended in c/s 7eaec00 when libxl Remus support was
introduced into the protocol.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Update the libxc spec to indicate more sternly that TOOLSTACK records
should no longer be used.
Also, trim further toolstack infrastructure which should have gone in
c/s 39bf4e9 "tools/libxl: Drop all knowledge of toolstack callbacks"
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
As implemented here, only supported on platforms with VMX HAP.
By default this functionality is force-disabled, it can be enabled
by specifying altp2m=1 on the Xen command line.
Signed-off-by: Ed White <edmund.h.white@intel.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
In setup_mm(), the value passed as xenheap_megabytes gets
converted to pages and passed to setup_xenheap_mappings(),
which in turn passes it to create_32mb_mappings(), which
contains an ASSERT that the value passed is a multiple of
32MB. So specifying any value that is not an integer multiple
of 32 will cause Xen to hit this assert and fail to boot.
Signed-off-by: Chris Brand <chris.brand@broadcom.com>
Reviewed-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
This patch introduces user configurable parameters to specify RDM
resource and according policies,
Global RDM parameter:
rdm = "strategy=host,policy=strict/relaxed"
Per-device RDM parameter:
pci = [ 'sbdf, rdm_policy=strict/relaxed' ]
Global RDM parameter, "strategy", allows user to specify reserved regions
explicitly, Currently, using 'host' to include all reserved regions reported
on this platform which is good to handle hotplug scenario. In the future
this parameter may be further extended to allow specifying random regions,
e.g. even those belonging to another platform as a preparation for live
migration with passthrough devices. By default this isn't set so we don't
check all rdms. Instead, we just check rdm specific to a given device if
you're assigning this kind of device. Note this option is not recommended
unless you can make sure any conflict does exist.
'strict/relaxed' policy decides how to handle conflict when reserving RDM
regions in pfn space. If conflict exists, 'strict' means an immediate error
so VM can't keep running, while 'relaxed' allows moving forward with a
warning message thrown out.
Default per-device RDM policy is same as default global RDM policy as being
'relaxed'. And the per-device policy would override the global policy like
others.
CC: Ian Jackson <ian.jackson@eu.citrix.com>
CC: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
CC: Ian Campbell <ian.campbell@citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Checked-by: Ian Jackson <ian.jackson@eu.citrix.com>
In a remus scenario, libxc will write a CHECKPOINT record, then hand
ownership of the fd to libxl. Libxl then writes any records required
and finishes with a CHECKPOINT_END record, then hands ownership of the
fd back to libxc.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
A platform may have a GIC compatible with previous version of the
device.
This is allow to virtualize an unmodified OS on new hardware if the GIC
is compatible with older version.
When a guest is created, the vGIC will emulate same version as the
hardware. Although, the user can specify in the configuration file the
preferred version (currently only GICv2 and GICv3 are supported).
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Usage:
hdtype=ide|ahci (default=ide)
If hdtype=ahci adds ich9 disk controller in ahci mode and uses it with
upstream qemu to emulate disks instead of ide.
It doesn't support cdroms which still using ide (cdroms will use
"-device ide-cd" as new qemu parameter)
Ahci requires new qemu parameter but for now other emulated disks cases
remains with old ones (I did it in other patch, not needed by this one)
I did it as libxl parameter disabled by default to avoid possible
problems:
- with save/restore/migration (restoring with ahci a domU that was with
ide instead)
- windows < 8 without pv drivers (a registry key change is needed for
AHCI<->IDE change FWIK to avoid possible blue screen)
- windows XP or older that many not support ahci by default.
Setting AHCI with libxl parameter and default to disabled seems the best
solution.
AHCI increase hvm domUs boot performance. On linux hvm domU I saw up to
only 20% of the previous total boot time, whereas boot time decrease a
lot on W7 domUs for most of boots I have done. Small difference in boot
time compared to ide mode on W8 and newer (probably other xen
improvements or fixes are needed not ahci related)
Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
[ ijc -- adjust name of LIBXL_HAVE #define as discussed on list,
fixup pod syntax in xl.cfg.pod.5 ]
Add document to introduce basic concepts and terms in PSR family
technologies and the xl interfaces.
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
This is the xc/xl changes to support Intel Cache Allocation
Technology(CAT).
'xl psr-hwinfo' is updated to show CAT info and two new commands
for CAT are introduced:
- xl psr-cat-cbm-set [-s socket] <domain> <cbm>
Set cache capacity bitmasks(CBM) for a domain.
- xl psr-cat-show <domain>
Show CAT domain information.
Examples:
[root@vmm-psr vmm]# xl psr-hwinfo --cat
Cache Allocation Technology (CAT):
Socket ID : 0
L3 Cache : 12288KB
Maximum COS : 15
CBM length : 12
Default CBM : 0xfff
[root@vmm-psr vmm]# xl psr-cat-cbm-set 0 0xff
[root@vmm-psr vmm]# xl psr-cat-show
Socket ID : 0
L3 Cache : 12288KB
Default CBM : 0xfff
ID NAME CBM
0 Domain-0 0xff
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Reviewed-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Detect Intel Cache Allocation Technology(CAT) feature and store the
cpuid information for later use. Currently only L3 cache allocation is
supported. The L3 CAT features may vary among sockets so per-socket
feature information is stored. The initialization can happen either at
boot time or when CPU(s) is hot plugged after booting.
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Use -1 as notifier priority. Fix typos.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
A find option was forgotten in commit 6592bf60be
"docs: Look for documentation in sub-directories" resulting to get some
docs duplicated and other missing.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
The ARM documentation is living in a specific folder under misc. Until
now, it was skipped during building.
In order to avoid missing future directory, use find to look for a
specific file pattern through all the directory.
Note the we already use find in other Makefile.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
In combination with the per-active entry locks, the grant table lock
can be made a read-write lock since the majority of cases only the
read lock is required. The grant table read lock protects against
changes to the table version or size (which are done with the write
lock held).
The write lock is also required when two active entries must be
acquired.
The double lock is still required when updating IOMMU page tables.
With the lock contention being only on the maptrack lock (unless IOMMU
updates are required), performance and scalability is improved.
Based on a patch originally by Matt Wilson <msw@amazon.com>.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Split grant table lock into two separate locks. One to protect
maptrack free list (maptrack_lock) and one for everything else (lock).
Based on a patch originally by Matt Wilson <msw@amazon.com>.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Introduce a per-active entry spin lock to protect active entry state
The grant table lock must be locked before acquiring (locking) an
active entry.
This is a step in reducing contention on the grant table lock, but
will only do so once the grant table lock is turned into a read-write
lock.
Based on a patch originally by Matt Wilson <msw@amazon.com>.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
For example on Dell machines we see:
(XEN) 00000fed18000-00000fed19fff type=11 attr=8000000000000000
(XEN) Unknown cachability for MFNs 0xfed18-0xfed19
Let's allow them to be mapped as UC.
We also alter the 'efi-rs' to be 'efi=rs' or 'efi=no-rs'.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Olaf reports:
[ 146s] man/xl.pod.1 around line 1529: '=item' outside of any '=over'
[ 146s] man/xl.pod.1 around line 1531: You forgot a '=back' before '=head1'
[ 146s] POD document had syntax errors at /usr/bin/pod2text line 84.
[ 146s] Makefile:167: recipe for target 'txt/man/xl.1.txt' failed
[ 146s] make[1]: *** [txt/man/xl.1.txt] Error 255
Reported-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
The current base directory /var/xen/dump for domU dumps will be patched
to /var/lib/xen/dump by most distros to follow FHS.
This change does three things:
- change the default from /var/xen/dump to /var/lib/xen/dump
- provide a configure option to avoid patching the source.
- update docs to refer to the new default location
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
[ ijc -- s,/var,LOCALSTATEDIR, in help test, ran autogen.sh ]
Ian Jackson
Jan Beulich
Ian Campbell
Ross Lagerwall
Chao Peng
Andrew Cooper
Wei Liu
Ting-Wei Lan
Ed White
Chris (Christopher) Brand
Tiejun Chen
Julien Grall
Fabio Fantoni
Dario Faggioli
David Vrabel
Konrad Rzeszutek Wilk
Olaf Hering