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Simply use lookup_withval right away rather than doing a
standard lookup, checking for the wrong mapping, then
repeating with lookup_withval to get the right mapping.
If the data len is passed into the hash table
and saved there, then the hash table internals
do not need to assume that the data value is
a string at any point.
New hash table functions are added that allow for
multiple entries with the same key. Use of the
vgname_to_vgid hash table is converted to these
new functions since there are multiple entries
in vgname_to_vgid that have the same key (vgname).
When multiple VGs with the same name exist, commands
that reference only a VG name will fail saying the
VG could not be found (that error message could be
improved.) Any command that works with the select
option can access one of the VGs with -S vg_uuid=X.
vgrename is a special case that allows the first VG
name arg to be replaced by a uuid, which also works.
(The existing hash table implementation is not well
suited for handling this case, but it works ok with
the new extensions. Changing lvmetad to use its own
custom hash tables may be preferable at some point.)
Recent change 2c8d6f5c90
actually droped restart when the reason of failing open is missing
device completely - check for ENOENT now as another reason
to start new dmeventd server (when there is no systemd to maintain it).
While through all codepaths we never 'read' lock_id unless LCKF_CONVERT,
coverity cannot decrypt this.
As since it's usually better to pass in 'well-defined' data structures
preset lock_id to 0.
Use fputs() when printing plain string,
easier then fprintf which needs to parse it.
Also check fd before close is >= 0 -
it is - but coverity fail to see it, so eliminate
this false-positive warning.
Check for arg_vgid_lookup and arg_name_lookup not being NULL.
Drop checking arg_vgid and arg_name for NULL since they
are already dereference earlier - thus mostly must be NOT NULL.
(If that would be possible larger rework of this function would be
required).
Put calls related to fifo opening into a single function.
Fix Time-Of-Check-Time-Of-Use and use fstat()
and fchmod() on already opened fd instead of
checking first path and then risking to open something
different.
update_metadata and pv_found update the cached metadata;
these are both reworked to improve the code, organize it
by each possible state and transition, make it much more
clear what's changing, add more error checking and
handling, and add comments.
The state and content of the cache (hash tables) does not
change (apart from some things that didn't work before),
and the communication to/from commands does not change.
The implementation and organization of the code making
the state changes does change significantly.
One detail related to the content of the cache does change:
different hash tables do not reference the same memory any more;
the target values in each hash table are allocated and freed
individually.
If plugin's lvm command execution fails too often (>10 times),
there is no point to torture system more then necessary, just log
and drop monitoring in this case.
Improve event string parser to avoid unneeded alloc+free.
Daemon talk function uses '-' to mark NULL/missing field.
So restore the NULL pointer back on parser.
This should have made old tools like 'dmevent_tool' work again.
As now 'uuid' or 'dso' could become NULL and then be
properly used in _want_registered_device() function.
Since lvm2 always fill these parameters, this change should
have no effect on lvm2.
Older pthread library was missing 'trick'
in pthread_cleanup_pop() which lead to
compilation error:
error: label at end of compound statement
Use explicit ';' to fix it.
Implementing exit when 'dmeventd' is idle.
Default idle timeout set to 1 hour - after this time period
dmeventd will cleanly exit.
On systems with 'systemd' - service is automatically started with
next contact on dmeventd communication socket/fifo.
On other systems - new dmeventd starts again when lvm2 command detects
its missing and monitoring is needed.
Add support to unmonitor device when monitor recognizes there is
nothing to monitor anymore.
TODO: possibly API change with return value could be also used.
Redesign threading code:
- plugin registration runs within its new created thread for
improved parallel usage.
- wait task is created just once and used during whole plugin lifetime.
- event thread is based over 'events' filter being set - when
filter is 0, such thread is 'unused'.
- event loop is simplified.
- timeout thread is never signaling 'processing' thread.
- pending of events filter cnange is properly reported and
running event thread is signalled when possible.
- helgrind is not reporting problems.
Need here to keep control device opened while there is 'any' dso
plugin loaded - otherwise there would a race closing controlfd
inside lvm2 plugin while some other monitoring thread would
tried to execute another WAITEVENT task.
Move all DSO related function in front, so they could be easily
referenced from rest of code.
Add proper error paths with logging and error reporting.
Drop mutex locking when releasing DSO - since DSO is always
allocated and released in main 'event' processing thread.
If a host failed while holding a sanlock lease,
sanlock_acquire will by default block and wait
for the lease to expire before returning. We
want it to return with an error so we can retry
instead of blocking, which allows us to process
other lock operations.
(Enclose this in an ifdef until the new flag
appears in a sanlock release.)
Respect lvm2_log_fn prototype. The idea of 'reusing' print_log with
plain cast is causing very strange crashes with some older 'gcc' compilers.
So just do it cleanly...
Rework thread creation code to better use resources.
New code will not leak 'timeout' registered thread on error path.
Also if the thread already exist - avoid creation of thread
object and it's later destruction.
If the race is noticed during adding new monitoring thread,
such thread is put on cleanup list and -EEXIST is reported.
As we now use 'unified' logging macro system - we no longer need
to protect from change of logging function pointer - it's set
once at the start of dmeventd and not change anymore
(as lvm2 library no longer interferers here).
If lvmlockd acquires an lv lock for a command, but the
command exits before the reply, then the command has
not activated the lv and lvmlockd should unlock it.
This only applies when the lv was not already locked.
(There will always be a chance that the lv lock is held
while the lv is not active, i.e. if the command fails in
the small window between getting the lv lock and before
doing the activation. In that case, rerunning the
activation command corrects the inconsistency.)
This commit helps by automatically clearing the
inconsistency (lv locked by not activated) in the most
common case when the lv lock operation is slow to
complete and the command is canceled by the user.
This commit also adds and cleans up references to the
client id in a bunch of log messages, which is useful
to follow processing on each independent lock request.
This applies the same rule/logic to dlm VGs that has always
existed for sanlock VGs. Allowing a dlm VG to be removed
while its lockspace was still running on other hosts largely
worked, but there were difficult problems if another VG with
the same name was recreated. Forcing the VG lockspace to
be stopped, gives both sanlock and dlm VGs the same behavior.
This shortcut was added for an odd case that I do not
believe is relevant any more. Having an alternate
path for lockspace thread cleanup is a complication
that could lead to problems.
The dlm will often lose the lvb content, so we need to
check quite a few possibilities for lvb values that
were not being checked before.
Refactoring was required to pass the entire lvb value
back to the core code instead of the single value.
The only functional change should be detecting new
lvb states where metadata is now invalidated where
it wasn't before.
When an action is created by lvmlockd for itself,
there is no client to send the result to. Add
the NO_CLIENT flag to the action to skip sending
the result to a client.
Undo the part of the recent EREMOVED change which
automatically stopped the lockspace for a remotely
removed VG. It didn't always work (would not work
when lvb content was rebuilt in the dlm). This will
be handled better when the lvb content is controlled
more strictly.
Remove the optimization/shortcut for starting the dlm global
lockspace when it was already running.
Reenable automatically starting the dlm global lockspace
when a command attempts to use it and it's not yet started.
This had become disabled at some point.
Previously all stderr messages issued by spawned lvpoll command were reported
as INFO only. This made all such messages invisible in syslog or lvmpolld log
while running default configuration.
All lvpoll stderr messages are loged with WARN priority now and lvpoll
command exiting with retcode != 0 is logged with ERROR priority in
syslog and lvmpolld log
Include both the VG uuid and name in the lvmetad
set_vg_info message. This works around an obscure
problem where the VG uuid in lvmlockd is wrong
when one host removes a dlm VG, then creates a new
VG with the same name. If the dlm lockspace for
the initial VG was never stopped on another host,
that other host will be using the old uuid in its
lvmetad set_vg_info message. (That can be
corrected with a larger change, but this is an
effective workaround.)
set_vg_info previously accepted only vg uuid,
now accept both vg uuid and vg name. If the
uuid is provided, it's used just as before,
but if the uuid is not provided, or if it's
not found, then fall back to using the vg
name if that is provided.
lvmlockd would fail to recognize that the global lockspace
failed to start if the dlm wasn't running, so future attempts
to start the dlm global lockspace would do nothing, thinking
it was already running.
This was only used to return two flags indicating specific
reasons for a lock failure so that a more specific error
message could be printed by the command (lockspace had been
stopped, or lockspace had an error starting.)
Remove the list, given its limited usefulness, the fact it
would easily become inaccurate, and the fact it was causing
misleading error messages. The error conditions it was meant
to help could be reported differently.
This makes lvmlockd removal steps for dlm VGs closely match
sanlock VGs. Because dlm lockspaces are not required to be
stopped on all hosts before vgremove, there is an extra bit
for dlm lockspaces, where a flag is set in the VG lock lvb
indicating that the VG was removed. If other hosts happen
to use the VG lock they will see this flag and stop their
lockspace.
Single messages sent over unix sockets are limited in
size to /proc/sys/net/core/wmem_max, so send the 1MB
debug buffer in smaller chunks to avoid EMSGSIZE.
Also look for EAGAIN and retry sending for a limited
time when the reader is slower than the writer.
Also shift the location of that code so it's the same
as other requests.
With clusters larger than 3 nodes, the 32-byte debug buffer in
cpg_join_callback() is too small to contain all the node IDs, because
32-bit identifiers are generally rendered in 10 decimal digits. No fixed
size is good in all cases, but this is conditionally logged debug info,
so we can simply truncate it. Double the size, nevertheless.
The check for other sanlock lockspaces was not checking
that the lockspace type was sanlock, so if dlm lockspaces
were visible, they were wrongly included.
This adds the infrastructure, code paths, error reporting,
etc. to handle storage errors, or storage loss, under the
sanlock leases in a VG that is being used. The loss of
storage means sanlock cannot renew its leases, which means
that the host needs to stop using the shared VG before its
leases expire.
This still requires manually shutting down a VG that has
lost lease storage, e.g. unmounting file systems,
deactivating LVs in the VG. The next step is to
automatically use a command like blkdeactivate to do that.
/lib/log/log.c:88: warning[invalidScanfArgType_int]: %llu in format string (no. 2) requires 'unsigned long long *' but the argument type is 'long long *'.
daemons/lvmlockd/lvmlockd-core.c:791: error[uninitstring]: Dangerous usage of 'version' (strncpy doesn't always null-terminate it).
The dlm global lockspace is automatically added when the
first dlm VG lockspace is added. Reverse this by removing
the dlm global lockspace after the last dlm VG lockspace
is removed. (Remove old non-working code that did this
based on an old command that could explicitly add/remove
the dlm global lockspace.)
Make it possible to decide whether we want to initialize connections and
filters together with toolcontext creation.
Add "filters" and "connections" fields to struct
cmd_context_initialized_parts and set these in cmd_context.initialized
instance accordingly.
(For now, all create_toolcontext calls do initialize connections and
filters, we'll change that in subsequent patch appropriately.)
Add struct cmd_context_initialized_parts to wrap up information
about which cmd context pieces are initialized and add variable
of this struct type into struct cmd_context.
Also, move existing "config_initialized" variable that was directly
part of cmd_context into the new cmd_context.initialized wrapper.
We'll be adding more items into the struct cmd_context_initialized_parts
with subsequent patches...
This tries harder to avoid creating duplicate global locks in
sanlock VGs by refusing to create a new sanlock VG with a
global lock if other sanlock VGs exist that may have a gl.
Simply running concurrent copies of 'pvscan | true' is enough to make
clvmd freeze: pvscan exits on the EPIPE without first releasing the
global lock.
clvmd notices the client disappear but because the cleanup code that
releases the locks is triggered from within some processing after the
next select() returns, and that processing can 'break' after doing just
one action, it sometimes never releases the locks to other clients.
Move the cleanup code before the select.
Check all fds after select().
Improve some debug messages and warn in the unlikely event that
select() capacity could soon be exceeded.
When there are duplicate global locks, check if the gl
is still enabled each time a gl or vg lock is acquired
in the lockspace. Once one of the duplicates is disabled,
then other hosts will recognize that the issue is resolved
without needing to restart the lockspaces.
When lvmlockd is compiled without support for one of the
lock managers (sanlock or dlm), and a command tries to use
one of them, explain that in the error message.
lib/format1/import-export.c:167: var_deref_op: Dereferencing null pointer "vg->lvm1_system_id"
lib/cache/lvmetad.c:1023: var_deref_op: Dereferencing null pointer "this"
daemons/lvmlockd/lvmlockd-core.c:2659: check_after_deref: Null-checking "act" suggests that it may be null, but it has already been dereferenced on all paths leading to the check
/daemons/lvmetad/lvmetad-core.c:1024: check_after_deref: Null-checking "pvmeta" suggests that it may be null, but it has already been dereferenced on all paths leading to the check
... Using uninitialized value "lockd_state" when calling "lockd_vg"
(even though lockd_vg assigns 0 to the lockd_state, but it looks at
previous state of lockd_state just before that so we need to have
that properly initialized!)
libdm/libdm-report.c:2934: uninit_use_in_call: Using uninitialized value "tm". Field "tm.tm_gmtoff" is uninitialized when calling "_get_final_time".
daemons/lvmlockd/lvmlockctl.c:273: uninit_use_in_call: Using uninitialized element of array "r_name" when calling "format_info_r_action". (just added FIXME as this looks unfinished?)
lib/log/log.c:115: leaked_storage: Variable "st" going out of scope leaks the storage it points to
daemons/lvmpolld/lvmpolld-core.c:573: leaked_storage: Variable "cmdargv" going out of scope leaks the storage it points to
daemons/lvmlockd/lvmlockd-core.c:5341: leaked_handle: Handle variable "fd" going out of scope leaks the handle
daemons/lvmlockd/lvmlockctl.c:575: overwrite_var: Overwriting "able_vg_name" in "able_vg_name = strdup(optarg)" leaks the storage that "able_vg_name" points to
daemons/lvmlockd/lvmlockctl.c:571: overwrite_var: Overwriting "able_vg_name" in "able_vg_name = strdup(optarg)" leaks the storage that "able_vg_name" points to
daemons/lvmlockd/lvmlockctl.c:385: leaked_handle: Handle variable "s" going out of scope leaks the handle
if lvm2 is built with debug memory options dm_free() is not
mapped directly to std library's free(). This may cause memory corruption
as a line buffer may get reallocated in getline with realloc.
This is a temporary hotfix. Other debug memory failure needs to
be investigated and explained.
Add the ability to invalidate global or individual VG metadata.
The invalid state is returned to lvm commands along with the metadata.
This allows lvm commands to detect stale metadata from the cache and
reread the latest metadata from disk (in a subsequent patch.)
These changes do not change the protocol or compatibility between
lvm commands and lvmetad.
Global information
------------------
Global information refers to metadata that is not isolated
to a single VG , e.g. the list of vg names, or the list of pvs.
When an external system, e.g. a locking system, detects that global
information has been changed from another host (e.g. a new vg has been
created) it sends lvmetad the message: set_global_info: global_invalid=1.
lvmetad sets the global invalid flag to indicate that its cached data is
stale.
When lvm commands request information from lvmetad, lvmetad returns the
cached information, along with an additional top-level config node called
"global_invalid". This new info tells the lvm command that the cached
information is stale.
When an lvm command sees global_invalid from lvmated, it knows it should
rescan devices and update lvmetad with the latest information. When this
is complete, it sends lvmetad the message: set_global_info:
global_invalid=0, and lvmetad clears the global invalid flag. Further lvm
commands will use the lvmetad cache until it is invalidated again.
The most common commands that cause global invalidation are vgcreate and
vgextend. These are uncommon compared to commands that report global
information, e.g. vgs. So, the percentage of lvmetad replies containing
global_invalid should be very small.
VG information
--------------
VG information refers to metadata that is isolated to a single VG,
e.g. an LV or the size of an LV.
When an external system determines that VG information has been changed
from another host (e.g. an lvcreate or lvresize), it sends lvmetad the
message: set_vg_info: uuid=X version=N. X is the VG uuid, and N is the
latest VG seqno that was written. lvmetad checks the seqno of its cached
VG, and if the version from the message is newer, it sets an invalid flag
for the cached VG. The invalid flag, along with the newer seqno are saved
in a new vg_info struct.
When lvm commands request VG metadata from lvmetad, lvmetad includes the
invalid flag along with the VG metadata. The lvm command checks for this
flag, and rereads the VG from disk if set. The VG read from disk is sent
to lvmetad. lvmetad sees that the seqno in the new version matches the
seqno from the last set_vg_info message, and clears the vg invalid flag.
Further lvm commands will use the VG metadata from lvmetad until it is
next invalidated.
There are reports of unexplained ioctl failures when using dmeventd.
An explanation might be that the wrong value of errno is being used.
Change libdevmapper to store an errno set by from dm ioctl() directly
and provide it to the caller through a new dm_task_get_errno() function.
[Replaced f9510548667754d9209b232348ccd2d806c0f1d8]
as of now lvmpolld works as client utility for
querying running instance of lvmpolld server
on metadata, state, etc.
Currently the only request implemented is the '--dump'.
It prints out full lvmpolld state (mimics lvmdump -p command).
There are two reasons for this: first, this allows the client side to notice
that some PV has multiple devices associated with it and print appropriate
warnings. Second, if a duplicate device pops up and disappears, after this
change the original connection between the PV and device is not lost.
There is no benefit in waking-up all the waiters
when there is no actual change in lock state.
This avoid some unnecessarily ping-pong effects like:
Resource V_LVMTEST15724vg retrying lock in mode:WRITE...
Resource V_LVMTEST15724vg already locked lockid=40, mode:WRITE
Resource V_LVMTEST15724vg retrying lock in mode:WRITE...
Resource V_LVMTEST15724vg already locked lockid=40, mode:WRITE
Free (and clear) h.protocol string on daemon_open() error paths
so it's OK for caller to skip calling daemon_close() if returned
h.socket_fd is -1.
Close h.socket_fd in daemon_close() to avoid possible leak.
https://bugzilla.redhat.com/1164234
- closer to the recommendation of man-pages (7) if possible
- Add crossrefs
- Sort options and crossrefs
- Fix default timeout (60 secs) of -t
- Documents -I[auto]
Signed-off-by: Stéphane Aulery <saulery@free.fr>
LVM2.2.02.112/daemons/clvmd/clvmd.c:1131: warning[arrayIndexOutOfBoundsCond]: Array 'row[8]' accessed at index 8, which is out of bounds. Otherwise condition 'j==8' is redundant.
This code:
int i,j = 0;
...
for (i = 0; i < len; ++i) {
...
if ((j == 8) || (i + 1 == len)) {
for (;j < 8; ++j) {
...
}
...
j = 0;
}
}
Indeed - j is 0 at the beginning, then iterating till j < 8,
then always zeroed at the end of the outer loop - so "j" never
reaching value of 8 - the j == 8 condition is redundant.
When responding to DM_EVENT_CMD_GET_REGISTERED_DEVICE no longer
ignore threads that have already been unregistered but which
are still present.
This means the caller can unregister a device and poll dmeventd
to ensure the monitoring thread has gone away before removing
the device. If a device was registered and unregistered in quick
succession and then removed, WAITEVENT could run in parallel with
the REMOVE.
Threads are moved to the _thread_registry_unused list when they
are unregistered.
The warnings arg was used to enable logging of warnings
when reading a PV. This arg is turned into a set of flags
with the WARN_PV_READ flag matching the existing behavior.
A new flag WARN_INCONSISTENT is added that will cause
vg_read_internal() to log the "VG is not consistent"
warning so the various callers do not need to log
this warning themselves.
A new vg_read flag READ_WARN_INCONSISTENT is used from
reporting to enable the WARN_INCONSISTENT flag in
vg_read_internal.
[Committed by agk with cosmetic changes and tweaks.]
Cmirrord has endian bugs, which cause failure to lvcreate a mirrored lv
on s390.
- data_size is uint32, should not use xlate64 to convert, which will
cause data_size 0 after xlate.
- request_type and data_size still used by local(v5_data_switch),
should convert later. If request_type xlate too early, it will
cause request_type judge error; if data_size xlate too early, it
will cause coredump in case DM_ULOG_CLEAR_REGION.
- when receiving package in clog_request_from_network. vp[0] will always
be little endian. We could use xlate64(vp[0]) == vp[0] to decide if
the local node is little endian or not.
Signed-off-by: Lidong Zhong<lzhong@suse.com> & Liuhua Wang <lwang@suse.com>
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
The list of strings is used quite frequently and we'd like to reuse
this simple structure for report selection support too. Make it part
of libdevmapper for general reuse throughout the code.
This also simplifies the LVM code a bit since we don't need to
include and manage lvm-types.h anymore (the string list was the
only structure defined there).
Switch to allocate buffer from heap, since it might be potentially
bigger when extremaly large set of volumes would be monitored.
In case of allocation failure send ENOMEM message.
Also implicitelly ignore msg->size when msg->data is NULL.
Prior adding new reply to the list, check
if the reply thread is not already finished.
In that case discard adding message
(which would otherwise be leaked).
Use mutex to access localsock values, so check
num_replies when the thread is not yet finished.
Check for threadid prior the mutex taking
(though this check is probably not really needed)
Added complexity with extra reply mutex is not worth the troubles.
The only place which may slightly benefit from this mutex is timeout
and since this is rather error case - let's convert it to
localsock.mutex and keep it simple.
Move the pthread mutex and condition creation and destroy
to correct place right after client memory is allocatedd
or is going to be released.
In the original place it's been in race with lvm thread
which could have still unlock mutex while it's been already
destroyed.
When TEST_MODE flag is passed around the cluster,
it's been use in thread unprotected way, so it may have
influenced behaviour of other running parallel lvm commands
(activation/deactivation/suspend/resume).
Fix it by set/query function only under lvm mutex.
For hold_un/lock function calls check lock_flags bits directly.
If clvmd does not hold any lock, it should also not keep any opened
device.
The reason for this patch is, that refresh_toolcontext calls
dev_cache_exit() which destroys whole device cache (even those with
opened file) - previous patch added recovery path to avoid memory
corruption, but opened files are still bugs that need to be fixed.
So this patch certainly kills many internal mirror & raid tests,
since they leak opened file descriptors (when tests are executed
with 'abort_on_error').
Operate with lvm_thread_exit while holding lvm_thread_mutex.
Don't leave unfinished work in the lvm thread queue
and always finish all queued tasks before exit,
so no cmd struct is left in the list.
(in-release fix)
We have to close cluster in some predicatable way,
otherwise we may access released memory from different
threads.
So move closedown till the point we know all thread
are closed. New messages from cluster are discarded.
When multiple threads act on the same 'quit' variable
the order of exit becomes unpredictable.
So let the main_loop() finish first and then clean up
all queued lvm jobs.
Do not add any new work, when lvm_thread_exit is set.
Properly clean 'client' structure only for LOCAL_SOCK type.
(Fixes bug from commit 460c19df62)
(in release fix)
Also cleanup-up associated pthreads by using cleanup_zombie() function.
Since this function may change the list, restart scanning always from
the list header.
Note: couple following patches are necessary to make this working properly.
There are two types of CPG communications in a corosync cluster:
messages and state transitions. Cmirrord processes the state
transitions first.
When a cluster mirror issues a POSTSUSPEND, it signals the end of
cluster communication with the rest of the nodes in the cluster.
The POSTSUSPEND marks the last communication of the 'message'
type that will go around the cluster. The node then calls
cpg_leave which causes a final 'state transition' communication to
all of the nodes. Once the out-going node receives its own state
transition notice from the cluster, it finalizes the leave. At this
point, the state of the log is 'INVALID'; but it is possible that
there remains some cluster trafic that was queued up behind the
state transition that still wants to be processed. It is harmless
to attempt to dispatch any remaining messages - they won't be
delivered because the node is no longer in the cluster. However,
there was a warning message that was being printed in this case
that is now removed by this patch. The failure of the dispatch
created a false positive condition that triggered the message.
"%d" in buffer_append_vf is 64 bit wide. Using just `int` for the
variable will fetch more from va_list than intended and shifting
remaining arguments resulting in errors like:
Internal error: Bad format string at '#orphan'
When the last entry in the timeout queue is unregistered,
wakeup sleeping condition, so the thread is deleted earlier.
So the thread resource is release earlier.
Also when monitored with tools like valgrind this eliminites reported
leak.
Individual events are handled through separate threads,
so once we have more then a single thread in this eventwait
sleeping, we got race on the dm_log setting, since
if one event is timeout out on alarm, while another is still waiting,
then dm log has been restored to NULL and the next sigalarm
has been reported as error.
Fix it by introducing counter which is protected via mutex,
and only when the last event is released, logging is restored.
TODO: libdm seems to have some static vars which may audit
for this type of use.
This patch will releases allocated private resources from
startup. Needs previous dm_zalloc patch to ensure unset
private pointer is NULL.
TODO: check on real cluster.
cmirrord polls for messages on the kernel and cluster interfaces.
Sometimes it is possible for messages to be received on the cluster
interface and be waiting for processing while the node is in the
process of leaving the cluster group. When this happens, the
messages received on the cluster interface are attempted to be
dispatched, but an error is returned because the connection is no
longer valid. It is a harmless situation. So, if we get the
specific error (CS_ERR_BAD_HANDLE) and we know that we have left
the group, then simply don't print the message.
In cases where PV appears on a new device without disappearing from an old one
first, the device->pvid pointers could become ambiguous. This could cause the
ambiguous PV to be lost from the cache when a different PV comes up on one of
the ambiguous devices.
