When a domain performs a kexec (soft reset), libxl__build_pre() is
called with the existing domid. Calling libxl__cpuid_legacy() on the
existing domain fails since the cpuid policy has already been set, and
the guest isn't rebuilt and doesn't kexec.
xc: error: Failed to set d1's policy (err leaf 0xffffffff, subleaf 0xffffffff, msr 0xffffffff) (17 = File exists): Internal error
libxl: error: libxl_cpuid.c:494:libxl__cpuid_legacy: Domain 1:Failed to apply CPUID policy: File exists
libxl: error: libxl_create.c:1641:domcreate_rebuild_done: Domain 1:cannot (re-)build domain: -3
libxl: error: libxl_xshelp.c:201:libxl__xs_read_mandatory: xenstore read failed: `/libxl/1/type': No such file or directory
libxl: warning: libxl_dom.c:49:libxl__domain_type: unable to get domain type for domid=1, assuming HVM
During a soft_reset, skip calling libxl__cpuid_legacy() to avoid the
issue. Before commit 34990446ca, the libxl__cpuid_legacy() failure
would have been ignored, so kexec would continue.
Fixes: 34990446ca ("libxl: don't ignore the return value from xc_cpuid_apply_policy")
Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
I'm observing guest kexec trigger xenstored to abort on a double free.
gdb output:
Program received signal SIGABRT, Aborted.
__pthread_kill_implementation (no_tid=0, signo=6, threadid=140645614258112) at ./nptl/pthread_kill.c:44
44 ./nptl/pthread_kill.c: No such file or directory.
(gdb) bt
at ./nptl/pthread_kill.c:44
at ./nptl/pthread_kill.c:78
at ./nptl/pthread_kill.c:89
at ../sysdeps/posix/raise.c:26
at talloc.c:119
ptr=ptr@entry=0x559fae724290) at talloc.c:232
at xenstored_core.c:2945
(gdb) frame 5
at talloc.c:119
119 TALLOC_ABORT("Bad talloc magic value - double free");
(gdb) frame 7
at xenstored_core.c:2945
2945 talloc_increase_ref_count(conn);
(gdb) p conn
$1 = (struct connection *) 0x559fae724290
Looking at a xenstore trace, we have:
IN 0x559fae71f250 20230120 17:40:53 READ (/local/domain/3/image/device-model-dom
id )
wrl: dom 0 1 msec 10000 credit 1000000 reserve 100 disc
ard
wrl: dom 3 1 msec 10000 credit 1000000 reserve 100 disc
ard
wrl: dom 0 0 msec 10000 credit 1000000 reserve 0 disc
ard
wrl: dom 3 0 msec 10000 credit 1000000 reserve 0 disc
ard
OUT 0x559fae71f250 20230120 17:40:53 ERROR (ENOENT )
wrl: dom 0 1 msec 10000 credit 1000000 reserve 100 disc
ard
wrl: dom 3 1 msec 10000 credit 1000000 reserve 100 disc
ard
IN 0x559fae71f250 20230120 17:40:53 RELEASE (3 )
DESTROY watch 0x559fae73f630
DESTROY watch 0x559fae75ddf0
DESTROY watch 0x559fae75ec30
DESTROY watch 0x559fae75ea60
DESTROY watch 0x559fae732c00
DESTROY watch 0x559fae72cea0
DESTROY watch 0x559fae728fc0
DESTROY watch 0x559fae729570
DESTROY connection 0x559fae724290
orphaned node /local/domain/3/device/suspend/event-channel deleted
orphaned node /local/domain/3/device/vbd/51712 deleted
orphaned node /local/domain/3/device/vkbd/0 deleted
orphaned node /local/domain/3/device/vif/0 deleted
orphaned node /local/domain/3/control/shutdown deleted
orphaned node /local/domain/3/control/feature-poweroff deleted
orphaned node /local/domain/3/control/feature-reboot deleted
orphaned node /local/domain/3/control/feature-suspend deleted
orphaned node /local/domain/3/control/feature-s3 deleted
orphaned node /local/domain/3/control/feature-s4 deleted
orphaned node /local/domain/3/control/sysrq deleted
orphaned node /local/domain/3/data deleted
orphaned node /local/domain/3/drivers deleted
orphaned node /local/domain/3/feature deleted
orphaned node /local/domain/3/attr deleted
orphaned node /local/domain/3/error deleted
orphaned node /local/domain/3/console/backend-id deleted
and no further output.
The trace shows that DESTROY was called for connection 0x559fae724290,
but that is the same pointer (conn) main() was looping through from
connections. So it wasn't actually removed from the connections list?
Reverting commit e8e6e42279 "tools/xenstore: simplify loop handling
connection I/O" fixes the abort/double free. I think the use of
list_for_each_entry_safe is incorrect. list_for_each_entry_safe makes
traversal safe for deleting the current iterator, but RELEASE/do_release
will delete some other entry in the connections list. I think the
observed abort is because list_for_each_entry has next pointing to the
deleted connection, and it is used in the subsequent iteration.
Add a comment explaining the unsuitability of list_for_each_entry_safe.
Also notice that the old code takes a reference on next which would
prevents a use-after-free.
This reverts commit e8e6e42279.
This is XSA-425/CVE-2022-42330.
Fixes: e8e6e42279 ("tools/xenstore: simplify loop handling connection I/O")
Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
WRMSR Non-Serialising is an optimisation intended for cases where an MSR needs
updating, but architectural serialising properties are not needed.
In is anticipated that this will apply to most if not all MSRs modified on
context switch paths.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Protection Key Supervisor works in a very similar way to Protection Key User,
except that instead of a PKRU register used by the {RD,WR}PKRU instructions,
the supervisor protection settings live in MSR_PKRS and is accessed using
normal {RD,WR}MSR instructions.
PKS has the same problematic interactions with PV guests as PKU (more infact,
given the guest kernel's CPL), so we'll only support this for HVM guests for
now.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Using a tab for separating the command from the options in the output
of "xenstore-control help" results in a rather ugly list.
Use a fixed size for the command instead.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Today check_store() is only testing the correctness of the node tree.
Add verification of the accounting data (number of nodes) and correct
the data if it is wrong.
Do the initial check_store() call only after Xenstore entries of a
live update have been read. This is wanted to make sure the accounting
data is correct after a live update.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Make the xenstored internal trace configurable by adding classes
which can be switched on and off independently from each other.
Define the following classes:
- obj: Creation and deletion of interesting "objects" (watch,
transaction, connection)
- io: incoming requests and outgoing responses
- wrl: write limiting
Per default "obj" and "io" are switched on.
Entries written via trace() will always be printed (if tracing is on
at all).
Add the capability to control the trace settings via the "log"
command and via a new "--log-control" command line option.
Add a missing trace_create() call for creating a transaction.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Instead of using malloc() and friends, let the hashtable implementation
use the talloc framework.
This is more consistent with the rest of xenstored and it allows to
track memory usage via "xenstore-control memreport".
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Letting hashtable_remove() return the value of the removed element is
not used anywhere in Xenstore, and it conflicts with a hashtable
created specifying the HASHTABLE_FREE_VALUE flag.
So just drop returning the value.
This of course requires to free the value if the HASHTABLE_FREE_VALUE
was specified, as otherwise it would be a memory leak.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Instead of returning 0 or 1 let chk_domain_generation() return a
boolean value.
Simplify the only caller by removing the ret variable.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
clang 14 is complaining about a NULL dereference for constructs like:
domain_is_unprivileged(conn) ? conn->in : NULL
as it can't know that domain_is_unprivileged(conn) will return false
if conn is NULL.
Fix that by making domain_is_unprivileged() an inline function (and
related to that domid_is_unprivileged(), too).
In order not having to make struct domain public, use conn->id instead
of conn->domain->domid for the test.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
There are some places left where dom0 is associated with domid 0.
Use dom0_domid instead.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Rework the interface and the internals of the per-domain node
accounting:
- rename the functions to domain_nbentry_*() in order to better match
the related counter name
- switch from node pointer to domid as interface, as all nodes have the
owner filled in
- use a common internal function for adding a value to the counter
For the transaction case add a helper function to get the list head
of the per-transaction changed domains, enabling to eliminate the
transaction_entry_*() functions.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Move all code related to struct changed_domain from
xenstored_transaction.c to xenstored_domain.c.
This will be needed later in order to simplify the accounting data
updates in cases of errors during a request.
Split the code to have a more generic base framework.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Instead of storing a pointer to the path which is prepended to
relative paths in struct watch, just use the length of the prepended
path.
It should be noted that the now removed special case of the
relative path being "" in get_watch_path() can't happen at all.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Instead of special casing the permission handling and watch event
firing for the special watch paths "@introduceDomain" and
"@releaseDomain", use static dummy nodes added to the data base when
starting Xenstore.
The node accounting needs to reflect that change by adding the special
nodes in the domain_entry_fix() call in setup_structure().
Note that this requires to rework the calls of fire_watches() for the
special events in order to avoid leaking memory.
Move the check for a valid node name from get_node() to
get_node_canonicalized(), as it allows to use get_node() for the
special nodes, too.
In order to avoid read and write accesses to the special nodes use a
special variant for obtaining the current node data for the permission
handling.
This allows to simplify quite some code. In future sub-nodes of the
special nodes will be possible due to this change, allowing more fine
grained permission control of special events for specific domains.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Move the definition of the log() macro to xenstored_core.h in order
to make it usable from other source files, too.
While at it preserve errno from being modified.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Today finding a struct domain by its domain id requires to scan the
list of domains until finding the correct domid.
Add a hashlist for being able to speed this up. This allows to remove
the linking of struct domain in a list. Note that the list of changed
domains per transaction is kept as a list, as there are no known use
cases with more than 4 domains being touched in a single transaction
(this would be a device handled by a driver domain and being assigned
to a HVM domain with device model in a stubdom, plus the control
domain).
Some simple performance tests comparing the scanning and hashlist have
shown that the hashlist will win as soon as more than 6 entries need
to be scanned.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
When a domain has been released by Xen tools, remove all its
registered watches. This avoids sending watch events to the dead domain
when all the nodes related to it are being removed by the Xen tools.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Today talloc_free() is not guaranteed to preserve errno, especially in
case a custom destructor is being used.
So preserve errno in talloc_free().
This allows to remove some errno saving outside of talloc.c.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
The configure option "--enable-trace-backend" isn't accepted anymore
and we should use "--enable-trace-backends" instead which was
introduce in 2014 and allow multiple backends.
"--enable-trace-backends" was introduced by:
5b808275f3bb ("trace: Multi-backend tracing")
The backward compatible option "--enable-trace-backend" is removed by
10229ec3b0ff ("configure: remove backwards-compatibility and obsolete options")
As we already use ./configure options that wouldn't be accepted by
older version of QEMU's configure, we will simply use the new spelling
for the option and avoid trying to detect which spelling to use.
We already make use if "--firmwarepath=" which was introduced by
3d5eecab4a5a ("Add --firmwarepath to configure")
which already include the new spelling for "--enable-trace-backends".
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Now that we have them available in a header which is okay to use from
hvmloader sources, do away with respective literal numbers and silent
assumptions.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper@citrix.com>
This function is unusued (only Xs_ring.write_substring is used), and the
bytes/string conversion here is backwards: the C stub implements the bytes
version and then we use a Bytes.unsafe_of_string to convert a string into
bytes.
However the operation here really is read-only: we read from the string and
write it to the ring, so the C stub should implement the read-only string
version, and if needed we could use Bytes.unsafe_to_string to be able to send
'bytes'. However that is not necessary as the 'bytes' version is dropped above.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
The manually established link order is fragile to code changes. Use ocamldep
to calculate the appropriate link order.
No functional change.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
This is not strictly necessary since it is essentially a no-op currently: a
cast to void * and value *, even in OCaml 5.0.
However it does make it clearer that what we have here is not a regular OCaml
value, but one allocated with Abstract_tag or Custom_tag, and follows the
example from the manual more closely:
https://v2.ocaml.org/manual/intfc.html#ss:c-outside-head
It also makes it clearer that these modules have been reviewed for
compat with OCaml 5.0.
We cannot use OCaml finalizers here, because we want exact control over when
to unmap these pages from remote domains.
No functional change.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
The field 'base' in 'struct libxl_device_virtio' is defined as uint64,
while we are printing it with '%lu', which is 32bit only 32-bit
platforms. And so generates a error like:
libxl_internal.h:4388:51: error: format '%lu' expects argument of type 'long
unsigned int', but argument 3 has type 'uint64_t' {aka 'long long unsigned
int'} [-Werror=format=]
Fix it by switching to a 64bit PRI instead.
While fixing this, switch from decimal to hex which is the more natural base
to use for a field like this.
Fixes: 43ba5202e2 ("libxl: add support for generic virtio device")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
This patch adds basic support for parsing generic Virtio backend.
An example of domain configuration for mmio based Virtio I2C device is:
virtio = ["type=virtio,device22,transport=mmio"]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
This patch adds basic support for configuring and assisting generic
Virtio backends, which could run in any domain.
An example of domain configuration for mmio based Virtio I2C device is:
virtio = ["type=virtio,device22,transport=mmio"]
To make this work on Arm, allocate Virtio MMIO params (IRQ and memory
region) and pass them to the backend and update guest device-tree to
create a DT node for the Virtio devices.
Add special support for I2C and GPIO devices, which require the
"compatible" DT property to be set, among other device specific
properties. Support for generic virtio devices is also added, which just
need a MMIO node but not any special DT properties, for such devices the
user needs to pass "virtio,device" in the "type" string.
The parsing of generic virtio device configurations will be done in a
separate commit.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Today it is possible to set a flag when calling hashtable_destroy() in
order to specify whether the data associated with the hashtable entries
should be freed or not. The keys of the entries will always be freed.
Change that by replacing the flag of hashtable_destroy() by two flags
for create_hashtable() which will specify whether the data and/or the
key of each entry should be freed or not.
This will enable users to have the key e.g. as part of the data.
Add a new function hashtable_iterate() to call a user specified
function for each entry in the hashtable.
Add new primes to the primetable in order to support smaller sizes of
the hashtable. The primes are selected according to:
https://planetmath.org/goodhashtableprimes
Update the URL in the source as the old one wasn't correct any longer.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Let corrupt() preserve errno in order to be able to simplify error
handling in future.
This is rather easy as the errno value when entering corrupt() is
saved already.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
tdb_logger() is called by TDB for logging errors. As errno is checked
often after doing the logging, tdb_logger() should preserve errno.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Use abort() instead of just _exit() in libxl__alloc_failed(). This
is more friendly for debugging, as it will trap into debugger,
systemd-coredump will collect coredump/backtrace etc. It's much more
useful than just "libxl: FATAL ERROR: memory allocation failure (...)"
message without context where it actually failed.
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
The iommu node will be required for other virtio device types too, not
just disk device.
Move the call to make_xen_iommu_node(), out of the disk device specific
block and rename "iommu_created" variable to "iommu_needed", and set it
to true for virtio disk device.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
make_virtio_mmio_node() creates the DT node for simple MMIO devices
currently, i.e. the ones that don't require any additional properties.
In order to allow using it for other complex device types, split the
functionality into two, one where the fdt node isn't closed and the
other one to create a simple DT node.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
In order to prepare for adding support for more device types, create a
separate routine to allocate base and irq for a device as the same code
will be required for other device types too.
Also move updates to virtio_irq and virtio_enabled out of the disk
device specific block, as they will depend on other device types too.
Suggested-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Not to be confused which hvm_get_param, which also exists and has a
different, more error-prone interface.
This one always returns a 64-bit value, and that is retained in the
OCaml binding as well, returning 'int64' (and not int, or nativeint
which might have different sizes).
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
There is no API or ioctl to query event channel status, it is only
present in xenctrl.h
The C union is mapped to an OCaml variant exposing just the value from
the correct union tag. This causes the xc bindings to now depend on
evtchn to get a useful API for EVTCHNSTAT_virq.
The information provided here is similar to 'lsevtchn', but rather than
parsing its output it queries the underlying API directly.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
fallback_exception_handler feeds a string with embedded newlines directly into
syslog(). While this is an improvement on getting nothing, syslogd escapes
all control characters it gets, and emits one (long) log line.
Fix the problem generally in the syslog stub. As we already have a local copy
of the string, split it in place and emit one syslog() call per line.
Also tweak Logging.msg_of to avoid putting an extra newline on a string which
already ends with one.
Fixes: ee7815f49f ("tools/oxenstored: Set uncaught exception handler")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
The binding for xc_interface_close() free the underlying handle while leaving
the Ocaml object still in scope and usable. This would make it easy to suffer
a use-after-free, if it weren't for the fact that the typical usage is as a
singleton that lives for the lifetime of the program.
Ocaml 5 no longer permits storing a naked C pointer in an Ocaml value.
Therefore, use a Custom block. This allows us to use the finaliser callback
to call xc_interface_close(), if the Ocaml object goes out of scope.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
strdup() may return NULL. Check for this before passing to syslog().
Drop const from c_msg. It is bogus, as demonstrated by the need to cast to
void * in order to free the memory.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Unhandled exceptions go to stderr by default, but this doesn't typically work
for oxenstored because:
* daemonize reopens stderr as /dev/null
* systemd redirects stderr to /dev/null too
Debugging an unhandled exception requires reproducing the issue locally when
using --no-fork, and is not conducive to figuring out what went wrong on a
remote system.
Install a custom handler which also tries to render the backtrace to the
configured syslog facility, and DAEMON|ERR otherwise.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
During live update, oxenstored tries a best effort approach to recover as many
domains and information as possible even if it encounters errors restoring
some domains.
However, logging about misunderstood input is more severe than simply info.
Log it at warning instead.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Closing the evtchn handle will unbind and free all local ports. The new
xenstored would need to rebind all evtchns, which is work that we don't want
or need to be doing during the critical handover period.
However, it turns out that the Windows PV drivers also rebind their local port
too across suspend/resume, leaving (o)xenstored with a stale idea of the
remote port to use. In this case, reusing the established connection is the
only robust option.
Therefore:
* Have oxenstored open /dev/xen/evtchn without CLOEXEC at start of day.
* Extend the handover information with the evtchn fd, domexc virq local port,
and the local port number for each domain connection.
* Have (the new) oxenstored recover the open handle using Xeneventchn.fdopen,
and use the provided local ports rather than trying to rebind them.
When this new information isn't present (i.e. live updating from an oxenstored
prior to this change), the best-effort status quo will have to do.
Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Inter-domain event channels are always a pair of local and remote ports.
Right now the handling is asymmetric, caused by the fact that the evtchn is
bound after the associated Domain object is constructed.
First, move binding of the event channel into the Domain.make() constructor.
This means the local port no longer needs to be an option. It also removes
the final callers of Domain.bind_interdomain.
Next, introduce a new port_pair type to encapsulate the fact that these two
should be updated together, and replace the previous port and remote_port
fields. This refactoring also changes the Domain.get_port interface (removing
an option) so take the opportunity to name it get_local_port instead.
Also, this fixes a use-after-free risk with Domain.close. Once the evtchn has
been unbound, the same local port number can be reused for a different
purpose, so explicitly invalidate the ports to prevent their accidental misuse
in the future.
This also cleans up some of the debugging, to always print a port pair.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Generally speaking, the event channel local/remote port is fixed for the
lifetime of the associated domain object. The exception to this is a
secondary XS_INTRODUCE (defined to re-bind to a new event channel) which pokes
around at the domain object's internal state.
We need to refactor the evtchn handling to support live update, so start by
moving the relevant manipulation into Domain.
No practical change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
This will make the logic clearer when we plumb local_port through these
functions.
While doing this, rearrange the construct in Domains.create0 to separate the
remote port handling from the interface handling. (The interface logic is
dubious in several ways, but not altered by this cleanup.)
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Xenstored always needs to bind the DOM_EXC VIRQ.
Instead of doing it shortly after the call to Event.init(), do it in the
constructor directly. This removes the need for the field to be a mutable
option.
It will also simplify a future change to support live update. Rename the
field from virq_port (which could be any VIRQ) to it's proper name.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
This file has some style problems so severe that they interfere with the
readability of the subsequent bugfix patches.
Fix these issues ahead of time, to make the subsequent changes more readable.
No functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Jason Andryuk