To stay in line with other parts of the ocaml code base.
This requires committing a bunch of mli files in tree.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Xen built with ocaml 4.06 gives errors such as
Error: This expression has type bytes but an expression was
expected of type string
as Byte and safe-strings which were introduced in 4.02 are the
default in 4.06.
This patch which is mostly by Richard W.M. Jones of Red Hat
from https://bugzilla.redhat.com/show_bug.cgi?id=1526703
fixes these issues.
v2: drop tools/ocaml/libs/xc/xenctrl.ml from the patch as the
affected code was removed by commit d933f1a53c
tools/ocaml: Drop coredump infrastructure
Signed-off-by: Michael Young <m.a.young@durham.ac.uk>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
[ wei: remove trailing whitespaces ]
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
c/s 4ddf474e2 "tools/xen-mceinj: Pass in GPA when injecting through
MSR_MCI_ADDR" removed the remaining user of hypercall.
It has been listed as broken, deprecated and wont-fix since XSA-74, so take
this opportunity to remove it completely.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Running "make uninstall" does not remove all installed files, a
situation which might cause link related issues if xen is re-installed
in a different location.
In order to make uninstall correctly remove the files it is best
the process should be done recursively by mirroring each "install"
target with an "uninstall" who removes the installed files.
An exception to this rule is uninstalling the files produced by
"qemu-xen-dir-remote" and "qemu-xen-traditional-dir", which are external
to the project. These projects do not implement an "uninstall" target so
the files have to be removed manually.
Signed-off-by: Petre Pircalabu <ppircalabu@bitdefender.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
There are no current users which I can locate. One piece of xend which didn't
move forwards into xl/libxl is this:
# Configure host CPUID consistency checks, which must be satisfied for this
# VM to be allowed to run on this host's processor type:
#cpuid_check=[ '1:ecx=xxxxxxxxxxxxxxxxxxxxxxxxxx1xxxxx' ]
# - Host must have VMX feature flag set
The implementation of xc_cpuid_check() is conceptually broken. Dom0's view of
CPUID is not the approprite view to check, and will be wrong in the presence
of CPUID masking/faulting, and for HVM-based toolstack domains.
If it turns out that the functionality is required, it should be implemented
in terms of XEN_SYSCTL_get_cpuid_policy to use the proper CPUID view.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
We were trimming the history of commits only at the end of each
transaction (regardless of how it ended).
Therefore if non-transactional writes were being made but no
transactions were being ended, the history would grow
indefinitely. Now we trim the history at regular intervals.
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
GCC 7.1.1 complains that several buffers passed to snprintf() in xenpmd
and tools/ocmal/xc are too small to hold the largest possible resulting string,
which is calculated by adding up the maximum length of all the substrings.
The warnings are treated as errors by -Werror, and goes like this (abbreviated):
xenpmd.c:94:36: error: ‘%s’ directive output may be truncated writing up to
255 bytes into a region of size 13 [-Werror=format-truncation=]
#define BATTERY_INFO_FILE_PATH "/proc/acpi/battery/%s/info"
^
xenpmd.c:113:13: note: ‘snprintf’ output between 25 and 280 bytes into a
destination of size 32
xenpmd.c:95:37: error: ‘%s’ directive output may be truncated writing up to
255 bytes into a region of size 13 [-Werror=format-truncation=]
#define BATTERY_STATE_FILE_PATH "/proc/acpi/battery/%s/state"
^
xenpmd.c:116:13: note: ‘snprintf’ output between 26 and 281 bytes into a
destination of size 32
xenctrl_stubs.c:65:15: error: ‘%s’ directive output may be truncated writing
up to 1023 bytes into a region of size 252 [-Werror=format-truncation=]
"%d: %s: %s", error->code,
^~
xenctrl_stubs.c:64:4: note: ‘snprintf’ output 5 or more bytes (assuming 1028)
into a destination of size 256
Enlarge the size of these buffers as suggested by the complier
(and slightly rounded) to fix the warnings.
No functional changes.
Signed-off-by: Zhongze Liu <blackskygg@gmail.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Only attempt to restore from saved state if it exists.
Without this, oxenstored immediately exits with an exception if the
--restart option is provided but the state file is not present.
(The time-of-check to time-of-use race isn't a concern as oxenstored is
the only thing that should write the state file.)
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
Previously, Domain.dump output the number of the local port
corresponding to each domain's event-channel. However, when oxenstored
exits, it closes /dev/xen/evtchn which causes the kernel to close the
local port (evtchn_release), so this port is no longer useful.
Instead, store the remote port. This can be used to reconnect the
event-channel by binding the original remote port to a fresh local port.
Indeed, the logic for parsing the stored state already expects a remote
port as it passes the parsed port number to Domain.make (via
Domains.create), which takes a remote port.
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
Internally, paths are represented as lists of strings, where
* path "/" is represented by []
* path "/local/domain/0" is represented by ["local"; "domain"; "0"]
(see comment for Store.Path.t).
However, the traversal function generated paths like
[""; "local"; "domain"; "0"]
because the name of the root node is "". Change it to generate paths
correctly.
Furthermore, the function passed to Store.dump_fct would render the node
"foo" under the path [] as "//foo". Change this to return "/foo".
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
For information related to transaction conflicts, potentially frequent
logging at "info" priority has been changed to "debug" priority, and
once per two minutes there is an "info" priority summary.
Additional detailed logging has been added at "debug" priority.
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
In the main loop, when choosing the timeout for the select function
call, we were setting it so as to wake up to issue conflict-credit to
any domains that could accept it. When xenstore is idle, this would
mean waking up every 50ms (by default) to do no work. With this
commit, we check whether any domain is below its cap, and if not then
we set the timeout for longer (the same timeout as before the
conflict-protection feature was added).
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
The packet telling us to end the transaction has always carried an
argument telling us whether to commit.
If the transaction made no modifications to the tree, now we ignore
that argument and do not commit: it is just a waste of effort.
This makes read-only transactions immune to conflicts, and means that
we do not need to store any of their details in the history that is
used for assigning blame for conflicts.
We count a transaction as a read-only transaction only if it contains
no operations that modified the tree.
This means that (for example) a transaction that creates a new node
then deletes it would NOT count as read-only, even though it makes no
change overall. A more sophisticated algorithm could judge the
transaction based on comparison of its initial and final states, but
this would add complexity and computational cost.
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
We already avoid inter-domain conflicts but now allow intra-domain
conflicts. Although there are no known practical examples of a domain
that might perform operations that conflict with its own transactions,
this is conceivable, so here we avoid changing those semantics
unnecessarily.
When a transaction commit fails with a conflict and we look through
the history of commits to see which connection(s) to blame, ignore
historical commits that were made by the same connection as the
failing commit.
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
Blame each connection found to have made a commit that would cause this
transaction to fail. Each blamed connection is penalised by having its
conflict-credit decremented.
Note the change in semantics for the replay function: we no longer stop after
finding the first operation that can't be replayed. This allows us to identify
all operations that conflicted with this transaction, not just the one that
conflicted first.
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
v1 Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Changes since v1:
* use correct log levels for informational messages
Changes since v2:
* fix the blame algorithm and improve logging
(fix was reviewed by Jonathan Davies)
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Since the list of historic activity cannot grow without bound, it is safe to use
this to track commits.
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Thomas Sanders <thomas.sanders@citrix.com>
The history of commits is to be used for working out which historical
commit(s) (including atomic writes) caused conflicts with a
currently-failing commit of a transaction. Any commit that was made
before the current transaction started cannot be relevant. Therefore
we never need to keep history from before the start of the
longest-running transaction that is open at any given time: whenever a
transaction ends (with or without a commit) then if it was the
longest-running open transaction we can delete history up until start
of the the next-longest-running open transaction.
Some transactions might stay open for a very long time, so if any
transaction exceeds conflict_max_history_seconds then we remove it
from consideration in this context, and will not guarantee to keep
remembering about historical commits made during such a transaction.
We implement this by keeping a list of all open transactions that have
not been open too long. When a transaction ends, we remove it from the
list, along with any that have been open longer than the maximum; then
we delete any history from before the start of the longest-running
transaction remaining in the list.
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
There is no need to record "read" operations as they will never cause another
transaction to fail.
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Thomas Sanders <thomas.sanders@citrix.com>
Forward port to xen-unstable:
* Remove Xenbus.Xb.Op.Restrict
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Add ability to track xenstore tree operations -- either non-transactional
operations or committed transactions.
For now, the call to actually retain commits is commented out because history
can grow without bound.
For now, we call record_commit for all non-transactional operations. A
subsequent patch will make it retain only the ones with side-effects.
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
When processing connections, skip those from domains with no remaining
conflict-credit.
Also, issue a point of conflict-credit at regular intervals, the
period being set by the configuration option "conflict-max-history-
seconds". When issuing conflict-credit, we give a point either to
every domain at once (one each) or only to the single domain at the
front of the queue, depending on the configuration option
"conflict-rate-limit-is-aggregate".
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
This commit gives each domain a conflict-credit variable, which will
later be used for limiting how often a domain can cause other domain's
transaction-commits to fail.
This commit also provides functions and data for manipulating domains
and their conflict-credit, and checking whether they have credit.
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
XS_RESTRICT and the xenstore library function xs_restrict() have never
been usable in all configurations and there are no known users.
This functionality was thought to limit access rights of device models
to xenstore in order to avoid affecting other domains in case of a
security breech. Unfortunately XS_RESTRICT won't help as current
qemu is requiring access to dom0 only accessible xenstore paths to
work correctly. So this command is useless and should be removed.
In order to avoid problems in the future remove all support for
XS_RESTRICT from xenstore.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: David Scott <dave@recoil.org>
In a 32bit build, the ocaml code 'proposed_id >= 0x7fffffff' compiles to:
8055eac: 83 fb ff cmp $0xffffffff,%ebx
8055eaf: 7d 0f jge 8055ec0 <...+0x20>
which in C is 'proposed_id >= INT_MIN', or in other words, tautologically
true. As a result, 32bit builds of oxenstored always try to allocate the
transaction id 1, and fall into an infinite loop of trying the next id if
transaction 1 is already in use.
Restrict the range down to 1 billion, to sit in the positive half of a 31 bit
ocaml integer. The compiled code is now:
8055eac: b9 ff ff ff 7f mov $0x7fffffff,%ecx
8055eb1: 39 cb cmp %ecx,%ebx
8055eb3: 7d 0b jge 8055ec0 <...+0x20>
which (other than non-optimal code generation because of the unnecessary use
of %ecx), isn't unconditionally true.
In principle, the check could be changed to 'proposed_id == 0x7fffffff' which
would still allow for 2 billion transaction in 32bit builds. However, in
64bit builds, this reintroduces a risk that if proposed_id is initially
greater than 0x7fffffff, it will not be clipped suitably into range.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: David Scott <dave@recoil.org>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
The transaction id of 0 is reserved, meaning "not in a transaction". It is up
to the xenstored server to allocate transaction ids. While oxenstored starts
its ids at 1, but insufficient care is taken with truncation cases.
A 32bit oxenstored has an int with 31 bits of width, meaning that the
transaction id will wrap around to 0 after 2 billion transactions.
A 64bit oxenstored has an int with 63 bits of width, meaning that once 4
billion transactions are used, the allocated id will be truncated when written
into the uin32_t field in the ring. This causes the client to reply with the
truncated id, breaking any further attempt to use any transactions.
Limit all transaction ids to the range between 1 and 0x7ffffffe. This is the
best which can be done without making oxenstored depend on Stdint or Cstruct,
yet still work for 32bit builds.
Also check that the proposed new transaction id isn't currently in use. For
the first 2 billion transactions there is no chance of a collision, and after
that, the chance is at most 20 (the default open transaction quota) in 2
billion.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: David Scott <dave@recoil.org>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
On a system with systemd the xenstore sockets are created via systemd.
Remove the related configuration files in order to be able to decide
at runtime whether the sockets should be created or not. This will
enable Xen to start xenstore either via a daemon or via a stub domain.
As the xenstore domain start program will exit after it has done its
job prepare the same behaviour to be tolerated by systemd for the
xenstore daemon by specifying the appropriate flags in the service
file.
A rerun of autogen.sh is required.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: David Scott <dave@recoil.org>
Move default the pid file under XEN_RUN_DIR. Note that it changes the
location from /var/run to /var/run/xen.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: David Scott <dave@recoil.org>
Only contain changes to ocaml source code. C stub files will be handled
separately.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: David Scott <dave@recoil.org>
We generate a corresponding constant (in lower case) in paths.ml. Use
that in source code to get rid of hard-coded path.
Note that with this patch the default location for xenstored*.log is
changed from /var/log to /var/log/xen.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: David Scott <dave@recoil.org>
That file includes all paths generated by configure. It will be used to
get rid of hard-coded paths in code.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: David Scott <dave@recoil.org>
Generate oxenstored.conf with configure. This involves modifying
tools/configure.ac and rerun autogen.sh.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
By explicitly casting it to unsigned.
Reasoning on why this is needed, provided by Andrew Cooper:
"Ocaml stores integers shifted left by one, and with the bottom bit set.
Values with the bottom bit clear are pointers into the GC'd heap. Values
with the bottom bit set are integers, and need to be shifted by 1 bit to
have calculations performed."
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>