XenStored will kill any connection that it thinks has misbehaved,
this is currently happening in two places:
* In `handle_input()` if the sanity check on the ring and the message
fails.
* In `handle_output()` when failing to write the response in the ring.
As the domain structure is a child of the connection, XenStored will
destroy its view of the domain when killing the connection. This will
result in sending @releaseDomain event to all the watchers.
As the watch event doesn't carry which domain has been released,
the watcher (such as XenStored) will generally go through the list of
domains registers and check if one of them is shutting down/dying.
In the case of a client misbehaving, the domain will likely to be
running, so no action will be performed.
When the domain is effectively destroyed, XenStored will not be aware of
the domain anymore. So the watch event is not going to be sent.
By consequence, the watchers of the event will not release mappings
they may have on the domain. This will result in a zombie domain.
In order to send @releaseDomain event at the correct time, we want
to keep the domain structure until the domain is effectively
shutting-down/dying.
We also want to keep the connection around so we could possibly revive
the connection in the future.
A new flag 'is_ignored' is added to mark whether a connection should be
ignored when checking if there are work to do. Additionally any
transactions, watches, buffers associated to the connection will be
freed as you can't do much with them (restarting the connection will
likely need a reset).
As a side note, when the device model were running in a stubdomain, a
guest would have been able to introduce a use-after-free because there
is two parents for a guest connection.
This is XSA-325.
Reported-by: Pawel Wieczorkiewicz <wipawel@amazon.de>
Signed-off-by: Harsha Shamsundara Havanur <havanur@amazon.com>
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
By setting a watch with a very large tag it is possible to trick
xenstored to send watch event messages exceeding the maximum allowed
payload size. This might in turn lead to a crash of xenstored as the
resulting error can cause dereferencing a NULL pointer in case there
is no active request being handled by the guest the watch event is
being sent to.
Fix that by just dropping such watch events. Additionally modify the
error handling to test the pointer to be not NULL before dereferencing
it.
This is XSA-324.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Currently, oxenstored checks the length of paths against 1024, then
prepends "/local/domain/$DOMID/" to relative paths. This allows a domU
to create paths which can't subsequently be read by anyone, even dom0.
This also interferes with listing directories, etc.
Define a new oxenstored.conf entry: quota-path-max, defaulting to 1024
as before. For paths that begin with "/local/domain/$DOMID/" check the
relative path length against this quota. For all other paths check the
entire path length.
This ensures that if the domid changes (and thus the length of a prefix
changes) a path that used to be valid stays valid (e.g. after a
live-migration). It also ensures that regardless how the client tries
to access a path (domid-relative or absolute) it will get consistent
results, since the limit is always applied on the final canonicalized
path.
Delete the unused Domain.get_path to avoid it being confused with
Connection.get_path (which differs by a trailing slash only).
Rewrite Util.path_validate to apply the appropriate length restriction
based on whether the path is relative or not. Remove the check for
connection_path being absolute, because it is not guest controlled data.
This is part of XSA-323.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
domain ids are prone to wrapping (15-bits), and with sufficient number
of VMs in a reboot loop it is possible to trigger it. Xenstore entries
may linger after a domain dies, until a toolstack cleans it up. During
this time there is a window where a wrapped domid could access these
xenstore keys (that belonged to another VM).
To prevent this do a cleanup when a domain dies:
* walk the entire xenstore tree and update permissions for all nodes
* if the dead domain had an ACL entry: remove it
* if the dead domain was the owner: change the owner to Dom0
This is done without quota checks or a transaction. Quota checks would
be a no-op (either the domain is dead, or it is Dom0 where they are not
enforced). Transactions are not needed, because this is all done
atomically by oxenstored's single thread.
The xenstore entries owned by the dead domain are not deleted, because
that could confuse a toolstack / backends that are still bound to it
(or generate unexpected watch events). It is the responsibility of a
toolstack to remove the xenstore entries themselves.
This is part of XSA-322.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Access rights of Xenstore nodes are per domid. Unfortunately existing
granted access rights are not removed when a domain is being destroyed.
This means that a new domain created with the same domid will inherit
the access rights to Xenstore nodes from the previous domain(s) with
the same domid.
This can be avoided by adding a generation counter to each domain.
The generation counter of the domain is set to the global generation
counter when a domain structure is being allocated. When reading or
writing a node all permissions of domains which are younger than the
node itself are dropped. This is done by flagging the related entry
as invalid in order to avoid modifying permissions in a way the user
could detect.
A special case has to be considered: for a new domain the first
Xenstore entries are already written before the domain is officially
introduced in Xenstore. In order not to drop the permissions for the
new domain a domain struct is allocated even before introduction if
the hypervisor is aware of the domain. This requires adding another
bool "introduced" to struct domain in xenstored. In order to avoid
additional padding holes convert the shutdown flag to bool, too.
As verifying permissions has its price regarding runtime add a new
quota for limiting the number of permissions an unprivileged domain
can set for a node. The default for that new quota is 5.
This is part of XSA-322.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Julien Grall <julien@amazon.com>
There are flags to turn off quotas and the permission system, so add one
that turns off the newly introduced watch permission checks as well.
This is part of XSA-115.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Today watch events are sent regardless of the access rights of the
node the event is sent for. This enables any guest to e.g. setup a
watch for "/" in order to have a detailed record of all Xenstore
modifications.
Modify that by sending only watch events for nodes that the watcher
has a chance to see otherwise (either via direct reads or by querying
the children of a node). This includes cases where the visibility of
a node for a watcher is changing (permissions being removed).
Permissions for nodes are looked up either in the old (pre
transaction/command) or current trees (post transaction). If
permissions are changed multiple times in a transaction only the final
version is checked, because considering a transaction atomic the
individual permission changes would not be noticable to an outside
observer.
Two trees are only needed for set_perms: here we can either notice the
node disappearing (if we loose permission), appearing
(if we gain permission), or changing (if we preserve permission).
RM needs to only look at the old tree: in the new tree the node would be
gone, or could have different permissions if it was recreated (the
recreation would get its own watch fired).
Inside a tree we lookup the watch path's parent, and then the watch path
child itself. This gets us 4 sets of permissions in worst case, and if
either of these allows a watch, then we permit it to fire. The
permission lookups are done without logging the failures, otherwise we'd
get confusing errors about permission denied for some paths, but a watch
still firing. The actual result is logged in xenstored-access log:
'w event ...' as usual if watch was fired
'w notfired...' if the watch was not fired, together with path and
permission set to help in troubleshooting
Adding a watch bypasses permission checks and always fires the watch
once immediately. This is consistent with the specification, and no
information is gained (the watch is fired both if the path exists or
doesn't, and both if you have or don't have access, i.e. it reflects the
path a domain gave it back to that domain).
There are some semantic changes here:
* Write+rm in a single transaction of the same path is unobservable
now via watches: both before and after a transaction the path
doesn't exist, thus both tree lookups come up with the empty
permission set, and noone, not even Dom0 can see this. This is
consistent with transaction atomicity though.
* Similar to above if we temporarily grant and then revoke permission
on a path any watches fired inbetween are ignored as well
* There is a new log event (w notfired) which shows the permission set
of the path, and the path.
* Watches on paths that a domain doesn't have access to are now not
seen, which is the purpose of the security fix.
This is part of XSA-115.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
The special watches "@introduceDomain" and "@releaseDomain" should be
allowed for privileged callers only, as they allow to gain information
about presence of other guests on the host. So send watch events for
those watches via privileged connections only.
Start to address this by treating the special watches as regular nodes
in the tree, which gives them normal semantics for permissions. A later
change will restrict the handling, so that they can't be listed, etc.
This is part of XSA-115.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
This will make it easier insert additional checks in a follow-up patch.
All watches are now fired from a single function.
This is part of XSA-115.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
The Xenstore command XS_IS_DOMAIN_INTRODUCED should be possible for privileged
domains only (the only user in the tree is the xenpaging daemon).
This is part of XSA-115.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Instead of ignoring the transaction id for XS_WATCH and XS_UNWATCH
commands as it is documented in docs/misc/xenstore.txt, it is tested
for validity today.
Really ignore the transaction id for XS_WATCH and XS_UNWATCH.
This is part of XSA-115.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Today watch events are sent regardless of the access rights of the
node the event is sent for. This enables any guest to e.g. setup a
watch for "/" in order to have a detailed record of all Xenstore
modifications.
Modify that by sending only watch events for nodes that the watcher
has a chance to see otherwise (either via direct reads or by querying
the children of a node). This includes cases where the visibility of
a node for a watcher is changing (permissions being removed).
This is part of XSA-115.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Paul Durrant <paul@xen.org>
The special watches "@introduceDomain" and "@releaseDomain" should be
allowed for privileged callers only, as they allow to gain information
about presence of other guests on the host. So send watch events for
those watches via privileged connections only.
In order to allow for disaggregated setups where e.g. driver domains
need to make use of those special watches add support for calling
"set permissions" for those special nodes, too.
This is part of XSA-115.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Paul Durrant <paul@xen.org>
There are several places in xenstored using a permission array and the
size of that array. Introduce a new struct node_perms containing both.
This is part of XSA-115.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Instead of firing all watches for removing a subtree in one go, do so
only when the related node is being removed.
The watches for the top-most node being removed include all watches
including that node, while watches for nodes below that are only fired
if they are matching exactly. This avoids firing any watch more than
once when removing a subtree.
This is part of XSA-115.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Today a Xenstore node is being removed by deleting it from the parent
first and then deleting itself and all its children. This results in
stale entries remaining in the data base in case e.g. a memory
allocation is failing during processing. This would result in the
rather strange behavior to be able to read a node (as its still in the
data base) while not being visible in the tree view of Xenstore.
Fix that by deleting the nodes from the leaf side instead of starting
at the root.
As fire_watches() is now called from _rm() the ctx parameter needs a
const attribute.
This is part of XSA-115.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Paul Durrant <paul@xen.org>
The Xenstore command XS_IS_DOMAIN_INTRODUCED should be possible for
privileged domains only (the only user in the tree is the xenpaging
daemon).
Instead of having the privilege test for each command introduce a
per-command flag for that purpose.
This is part of XSA-115.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Paul Durrant <paul@xen.org>
There is no path which allows to call check_event_node() without a
event name. So don't let the result depend on the name being NULL and
add an assert() covering that case.
Rename the function to check_special_event() to better match the
semantics.
This is part of XSA-115.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Paul Durrant <paul@xen.org>
When a node creation fails the number of nodes of the domain should be
the same as before the failed node creation. In case of failure when
trying to create a node requiring to create one or more intermediate
nodes as well (e.g. when /a/b/c/d is to be created, but /a/b isn't
existing yet) it might happen that the number of nodes of the creating
domain is not reset to the value it had before.
So move the quota accounting out of construct_node() and into the node
write loop in create_node() in order to be able to undo the accounting
in case of an error in the intermediate node destructor.
This is part of XSA-115.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Julien Grall <jgrall@amazon.com>
Instead of ignoring the transaction id for XS_WATCH and XS_UNWATCH
commands as it is documented in docs/misc/xenstore.txt, it is tested
for validity today.
Really ignore the transaction id for XS_WATCH and XS_UNWATCH.
This is part of XSA-115.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Paul Durrant <paul@xen.org>
An unprivileged user of Xenstore is not allowed to write nodes with a
size exceeding a global quota, while privileged users like dom0 are
allowed to write such nodes. The size of a node is the needed space
to store all node specific data, this includes the names of all
children of the node.
When deleting a node its parent has to be modified by removing the
name of the to be deleted child from it.
This results in the strange situation that an unprivileged owner of a
node might not succeed in deleting that node in case its parent is
exceeding the quota of that unprivileged user (it might have been
written by dom0), as the user is not allowed to write the updated
parent node.
Fix that by not checking the quota when writing a node for the
purpose of removing a child's name only.
The same applies to transaction handling: a node being read during a
transaction is written to the transaction specific area and it should
not be tested for exceeding the quota, as it might not be owned by
the reader and presumably the original write would have failed if the
node is owned by the reader.
This is part of XSA-115.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Paul Durrant <paul@xen.org>
This was lacking in a disappointing number of places.
The xenstore root node is treated differently from all other nodes, because it
doesn't have a parent, and mutation requires changing the parent.
Unfortunately this lead to open-coding the special case for root into every
single xenstore operation, and out of all the xenstore operations only read
did a permission check when handling the root node.
This means that an unprivileged guest can:
* xenstore-chmod / to its liking and subsequently write new arbitrary nodes
there (subject to quota)
* xenstore-rm -r / deletes almost the entire xenstore tree (xenopsd quickly
refills some, but you are left with a broken system)
* DIRECTORY on / lists all children when called through python
bindings (xenstore-ls stops at /local because it tries to list recursively)
* get-perms on / works too, but that is just a minor information leak
Add the missing permission checks, but this should really be refactored to do
the root handling and permission checks on the node only once from a single
function, instead of getting it wrong nearly everywhere.
This is XSA-353.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
This case can occur when combining empty lists
obj-y :=
...
obj-y += $(empty)
or
obj-y := $(empty) $(empty)
where (only) blanks would accumulate. This was only a latent issue until
now, but would become an active issue for Arm once lib/ gets populated
with all respective objects going into the to be introduced lib.a.
Also address a related issue at this occasion: When an empty built_in.o
gets created, .built_in.o.d will have its dependencies recorded. If, on
a subsequent incremental build, an actual constituent of built_in.o
appeared, the $(filter-out ) would leave these recorded dependencies in
place. But of course the linker won't know what to do with C header
files. (The apparent alternative of avoiding to pass $(c_flags) or
$(a_flags) would not be reliable afaict, as among these flags there may
be some affecting information conveyed via the object file to the
linker. The linker, finding inconsistent flags across object files, may
then error out.) Using just $(obj-y) won't work either: It breaks when
the same object file is listed more than once.
Reported-by: Julien Grall <julien@xen.org>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
There's no need to serialize all sending of vIRQ-s; all that's needed
is serialization against the closing of the respective event channels
(so far by means of a barrier). To facilitate the conversion, switch to
an ordinary write locked region in evtchn_close().
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Olaf reported observing
xenstat_qmp.c:26:10: fatal error: _paths.h: No such file or directory
.../tools/libs/stat/../../../tools/Rules.mk:153: xenstat_qmp.opic] Error 1
Obviously _paths.h, when included by any of the sources, needs to be
created in advance of compiling any of them, not just when compiling
into non-PIC objects.
Reported-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Wei Liu <wl@xen.org>
evtchn_fifo_set_pending() can be simplified a little bit. Especially
testing for the fifo control block to exist can be moved out of the
main if clause of the function enabling to avoid testing the LINKED bit
twice.
Suggested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
It mentions just stale and obsolete distributions.
They are not suitable to build current Xen, since a couple of years.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Wei Liu <wl@xen.org>
Fix the command line document to account for the default scheduler in
Kconfig being credit2 now, and the fact that it's selectable at build
time and thus different builds could end up with different default
schedulers.
Fixes: dafd936ddd ('Make credit2 the default scheduler')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wl@xen.org>
Instead of a pointer to an error variable as parameter just use
ERR_PTR() to return the cause of an error in cpupool_create().
This propagates to scheduler_alloc(), too.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Dario Faggioli <dfaggioli@suse.com>
Instead of open coding something like a linked list just use the
available functionality from list.h.
The allocation of a new cpupool id is not aware of a possible wrap.
Fix that. We don't, however, consider the case of extremely many pools
(beyond 4 billion) as something which needs explicitly handling right
now. First and foremost there would need to be systems with 4 billion
CPUs to make this many pools a sensible thing to have.
While adding the required new include to private.h sort the includes.
Signed-off-by: From: Juergen Gross <jgross@suse.com>
Reviewed-by: Dario Faggioli <dfaggioli@suse.com>
The cpupool id is an unsigned value in the public interface header, so
there is no reason why it is a signed value in struct cpupool.
Switch it to unsigned int.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Dario Faggioli <dfaggioli@suse.com>
There is simply no guarantee that vmap won't return superpages to the
caller. It can happen if the list of MFNs are contiguous, or we simply
have a large granularity. Although rare, if such things do happen, we
will simply hit BUG_ON() and crash.
Introduce xen_map_to_mfn() to translate any mapped Xen address to mfn
regardless of page size, and wrap vmap_to_mfn() around it.
Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
... instead of effectively open-coding it in a type-unsafe way. Drop the
regs_sz variable altogether, replacing other uses suitably.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
... instead of effectively open-coding it in a type-unsafe way. Drop
hvm_vioapic_size() altogether, folding the other use in a memset()
invocation into the subsequent loop.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
... and increase default "irq-max-guests" to 32.
It's not necessary to have an array of a size more than 1 for non-shareable
IRQs and it might impact scalability in case of high "irq-max-guests"
values being used - every IRQ in the system including MSIs would be
supplied with an array of that size.
Since it's now less impactful to use higher "irq-max-guests" value - bump
the default to 32. That should give more headroom for future systems.
Requested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
... and increase the default to 16.
Current limit of 7 is too restrictive for modern systems where one GSI
could be shared by potentially many PCI INTx sources where each of them
corresponds to a device passed through to its own guest. Some systems do not
apply due dilligence in swizzling INTx links in case e.g. INTA is declared as
interrupt pin for the majority of PCI devices behind a single router,
resulting in overuse of a GSI.
Introduce a new command line option to configure that limit and dynamically
allocate an array of the necessary size. Set the default size now to 16 which
is higher than 7 but could later be increased even more if necessary.
Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
A guest with memory < maxmem often can't be dumped via xl dump-core
without an error message today:
xc: info: exceeded nr_pages (262144) losing pages
In case the last page of the guest isn't allocated the loop in
xc_domain_dumpcore_via_callback() will always spit out this message,
as the number of already dumped pages is tested before the next page
is checked to be valid.
The guest's p2m_size might be lower than expected, so this should be
tested in order to avoid reading past the end of it.
The guest might use high bits in p2m entries to flag special cases like
foreign mappings. Entries with an MFN larger than the highest MFN of
the host should be skipped.
Signed-off-by: Juergen Gross <jgross@suse.com>
Introduce a helper function covering both the IRQ_GUEST check and the
cast involved in obtaining the (correctly typed) pointer. Where possible
add const and/or reduce variable scope.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
I didn't bother figuring which commit(s) should have deleted them while
removing their last uses.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
Adding the new value into the enumeration makes it immediately available
to xl, so this patch adjusts the xl.cfg(5) documentation accordingly.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
... and advertise ExProcessorMasks support if it is set.
Support is advertised by setting bit 11 in CPUID:40000004:EAX.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
To make is simpler to observe which viridian hypercalls are issued by a
particular Windows guest, this patch adds a per-domain mask to track them.
Each type of hypercall causes a different bit to be set in the mask and
when the bit transitions from clear to set, a log line is emitted showing
the name of the hypercall and the domain that issued it.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
A previous patch introduced variants of the flush hypercalls that take a
'Virtual Processor Set' as an argument rather than a simple 64-bit mask.
This patch introduces a similar variant of the HVCALL_SEND_IPI hypercall
(HVCALL_SEND_IPI_EX).
NOTE: As with HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE/LIST_EX, a guest should
not yet issue the HVCALL_SEND_IPI_EX hypercall as support for
'ExProcessorMasks' is not yet advertised via CPUID.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
The Microsoft Hypervisor TLFS specifies variants of the already implemented
HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE/LIST hypercalls that take a 'Virtual
Processor Set' as an argument rather than a simple 64-bit mask.
This patch adds a new hvcall_flush_ex() function to implement these
(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE/LIST_EX) hypercalls. This makes use of
new helper functions, hv_vpset_nr_banks() and hv_vpset_to_vpmask(), to
determine the size of the Virtual Processor Set (so it can be copied from
guest memory) and parse it into hypercall_vpmask (respectively).
NOTE: A guest should not yet issue these hypercalls as 'ExProcessorMasks'
support needs to be advertised via CPUID. This will be done in a
subsequent patch.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
vlapic_ipi() uses a softirq batching mechanism to improve the efficiency of
sending a IPIs to large number of processors. This patch modifies send_ipi()
(the worker function called by hvcall_ipi()) to also make use of the
mechanism when there multiple bits set the hypercall_vpmask.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wl@xen.org>
A subsequent patch will need to IPI a mask of virtual processors potentially
wider than 64 bits. A previous patch introduced per-cpu hypercall_vpmask
to allow hvcall_flush() to deal with such wide masks. This patch modifies
the implementation of hvcall_ipi() to make use of the same mask structures,
introducing a for_each_vp() macro to facilitate traversing a mask.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
... and make use of them in hvcall_flush()/need_flush().
Subsequent patches will need to deal with virtual processor masks potentially
wider than 64 bits. Thus, to avoid using too much stack, this patch
introduces global per-cpu virtual processor masks and converts the
implementation of hvcall_flush() to use them.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
This patch moves the implementation of HVCALL_SEND_IPI that is currently
inline in viridian_hypercall() into a new hvcall_ipi() function.
The new function returns Xen errno values similarly to hvcall_flush(). Hence
the errno translation code in viridial_hypercall() is generalized, removing
the need for the local 'status' variable.
NOTE: The formatting of the switch statement at the top of
viridial_hypercall() is also adjusted as per CODING_STYLE.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
This patch moves the implementation of HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE/LIST
that is currently inline in viridian_hypercall() into a new hvcall_flush()
function.
The new function returns Xen erro values which are then dealt with
appropriately. A return value of -ERESTART translates to viridian_hypercall()
returning HVM_HCALL_preempted. Other return values translate to status codes
and viridian_hypercall() returning HVM_HCALL_completed. Currently the only
values, other than -ERESTART, returned by hvcall_flush() are 0 (indicating
success) or -EINVAL.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
If hvm_guest_x86_mode() returns something other than 8 or 4 then
viridian_hypercall() will return immediately but, on the way out, will write
back status as if 'mode' was 4. This patch simply makes it leave the registers
alone.
NOTE: The formatting of the 'out' label and the switch statement are also
adjusted as per CODING_STYLE.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
Harsha Shamsundara Havanur
Juergen Gross
Edwin Török
Jan Beulich
Olaf Hering
Roger Pau Monne
Hongyan Xia
Igor Druzhinin
Paul Durrant