than discard characters in the console daemon buffers.
New option: -o, --overflow-data=discard|keep
This option changes the behaviour when dealing with data that overflow
the max capacity of the buffer. If overflow-data is set to discard
(the default), the current behaviour is used: we discard some data in
the middle of the buffer.
If overflow-data is set to keep, we stop listening to the ring until
we free some space in the buffer. This can cause the ring to fill up
and the guest kernel internal buffer to fill up as well. When this
happens the guest kernel stops reading characters from the console
device so the application generating data hangs. When xenconsoled
resumes reading from the ring, the guest kernel will be able to resume
reading from the console device as well. At that point the guest
application will be allowed to continue.
The risk of making this behaviour the default is that existing kernel
drivers may assume they can rely on timely ring updates by the console
daemon and thus themselves block on the ring being emptied.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Previously a newline was forced after every call to
write_with_timestamp. This could result in some ugly logs when a
single console line stretched over multiple calls. This change carries
some extra state to determine if we ended the last call to
write_with_timestamp on a newline, and prints the timestamp as
appropriate.
This also fixes a bug where logging hv messages was dependent on the
guest timestamp flag.
Signed-off-by: Cole Robinson <crobinso@redhat.com>
mb/rmb/wmb. Instead add a xen_ prefix. Modify Xen's public headers to
expect the prefixed names instead of bare mb/rmb/wmb, but gate this
expectation on a bump of __XEN_INTERFACE_VERSION__.
Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
Fix a number of problems with the pty handling:
- make openpty() implementation work on Solaris
- set raw on the slave fd, not the master, as the master doesn't
have a line discipline pushed on Solaris
- make sure we don't leak the slave fd returned from openpty()
- don't use the 'name' argument of openpty() as it's a security risk
- note behaviour of a zero read of the master on Solaris
- remove pointless tcget/setattr
Signed-off-by: John Levon <john.levon@sun.com>
Signed-off-by: Samuel Thibault <samuel.thibault@citrix.com>
shutdown_domain() MUST NOT call cleanup_domain(), just flagging them
as dead is enough. cleanup_domains() for dead domains is called by
the main loop in handle_io() in a safe way already.
shutdown_domain() calling cleanup_domain() too leads struct domain
being accessed after freeing and to a double-free.
Fixed by simply dropping the cleanup_domain() call and by making the
functions called by the main loop in handle_io() ignore dead domains.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This patch writes a field /local/vm/DOMID/console/type taking the
value 'ioemu' or 'xenconsoled'. If xenconsoled sees a type that is
not its own, then it skips handling of that guest. The qemu-dm
process doesn't need to read this field since it will only attach
to the console if given the -serial pty arg which XenD already
ensures matches this xenstore field.
The overall behaviour is that if a paravirt guest has a qemu-dm
process running then that handles the console, otherwise the
xenconsoled handles it. The former is more functional, with the
exception of not currently supporting persistent logging to a
file at the same time as exposing a PTY.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
- Use openpty(), which does the same as the sequence
of open(), grantpt(), unlockpt(), ptsname(), tcgetattr()
simplifies code
- Check return code from tcsetattr()
- sprintf() -> snprintf()
- OpenBSD lacks POSIX grantpt() and unlockpt()
requires use of openpty()
- Solaris lacks POSIX openpty() via feedback from SUN (John Levon)
implement openpty() for Solaris, tested and ok'd by SUN (John
Levon)
Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
- include headers needed to build on NetBSD
- Remove unused pty.h
- Initialize spty terminal before actually using it
Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
Check the 'log_reload' on every iteration of the select() loop, not just when
select() returns EINTR. This is because the log reload signal may have
iterrupted a syscall other than select & thus without this change we
might miss the reload signal. The second change makes us process the
hypervisor logs on every iteration of the loop, not just upon timeouts.
This is because if a guest VM were consistently sending some log message
and < 1 second period, the select() would never hit the 1 second timeout
and thus never process the HV logs.
Thanks to Markus Armbruster for pointing out both these edge cases
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Note that some of the existing error checking for asprintf was wrong
for Linux. asprintf in glibc returns -1 on error, but leaves the
pointer uninitialized. Only the BSDs zero out the pointer on error.
Also, while fixing these warnings I saw several error paths that were
incorrect. This patch minimally fixes the warn_unused_result; more
complete error path cleanup will be a later patch.
Signed-off-by: Charles Coffing <ccoffing@novell.com>
FC5's gcc 4.1.0 can't make some files in tools/ due to its stronger
type checking.
From: Dexuan Cui <dexuan.cui@intel.com>
Signed-off-by: Keir Fraser <keir@xensource.com>
* The --log command line argument takes one of 4 values
- none - no logging (the default)
- hv - log all hypervisor messages
- guest - log all guest messages
- both - log all guest & hypervisor messages
* The --log-dir command line argument takes a path to specify where
to store logfiles. If omitted it defaults to /var/log/xen/console
* The hypervisor logfile is $LOGDIR/hypervisor.log
* The guest logfile is $LOGDIR/guest-[NAME].log
* If receiving a SIGHUP it will close & re-open all log files to
enable logrotate to do its magic
* Fixes the permissions of /var/run/xenconsoled.pid
* Adds a --pid-file command line argument to override the default
location of pid file (this is not really related to logging, but
since I was in that code...)
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Support information in console/ in a backwards compatible fashion.
This puts the serial port information for pv domains at the same
location where it is for hvm domains.
Signed-off-by: Christian Limpach <Christian.Limpach@xensource.com>
There is a race condition between domain_create_ring() and the removal
of the domU entry from xenstore. If the removal of the domU entry from xenstore
comes later than the first xs_gather() call in domain_create_ring(), it will go
on and bind the evtchn port to the dying domU, which will cause below error
message: (XEN) (file=event_channel.c, line=144) EVTCHNOP failure: domain 0, error -22, line 144
Signed-off-by: Max Zhen <max.zhen@sun.com>
because it uses FD_ISSET(-1,xxx). Since the code is written that any
ring/tty handler can set d->tty_fd to -1 it has to be checked
_every_time_.
Signed-off-by: Jimi Xenidis <jimix@watson.ibm.com>
No longer open the device as non-blocking: all reads immediately follow
a select() on the device indicating it's ready to read.
Signed-off-by: John Levon <john.levon@sun.com>
through the buffer when the data are read by console clients. This avoids a
costly memmove with every read from the console.
Signed-off-by: Ewan Mellor <ewan@xensource.com>
if the console client disconnected before all the data had been written to the
pty, even though the select call had indicated that the fd was previously
writable. Reads have been observed exhibiting similar behaviour too.
Closes bug #380.
Signed-off-by: Ewan Mellor <ewan@xensource.com>
the domain has gone away, then no-one can attach to the pty because Xend will
have cleaned up the entries in the store, so the pty will never become ready to
write. The buffer will never get emptied, so cleanup will never occur. This
leaks ptys, file descriptors, and memory. Simply throw those data away instead.
Signed-off-by: Ewan Mellor <ewan@xensource.com>
buffer that has grown beyond max_capacity. This fixes a Xenconsoled segfault
that was caused by stomping around above the buffer's allocated region. It
became possible to set the max_capacity with changeset 7431, and ever
since then we have been exposed to this bug. It would most easily be triggered
by running a domain without a client attached to the console, so that the
max_capacity was reached more easily.
Closes bug #380.
Signed-off-by: Ewan Mellor <ewan@xensource.com>
domain has recently been removed from our list, but with a watch still in
flight. This should fix the intermittent crash in xenconsoled that is plaguing
us at the moment.
Signed-off-by: Ewan Mellor <ewan@xensource.com>
means that any reads attempted on that tty will not cause handle_tty_read to
segfault looking for an interface that does not exist.
Move the writing of the tty node so that it happens after console/limit has
been read, as it is cleaner if the writing is the last thing that happens.
Signed-off-by: Ewan Mellor <ewan@xensource.com>
whether a domain has been introduced to the store. Added a separate message
XS_IS_DOMAIN_INTRODUCED and API for that (xs_is_domain_introduced) to determine
whether the domain has really been introduced. This change means that the
tools can determine the correct domain path earlier in the domain creation
process, which is particularly a factor with live migration, as it allows us
to create the devices earlier in the process, and unpause the new domain before
performing the introduce. Until recently we already had these features, but
the simplification of the interface between xend and xenstored caused breakage.
No longer clear out the domain path when a domain is introduced -- this was a
hack to work around the recent problematic semantics of GetDomainPath.
Do not write the contents of the info block to the store. All the configuration
info is written to the /vm path, and anything else in the info block is either
dealt with explicitly or is ephemeral and has no place in the store.
Signed-off-by: Ewan Mellor <ewan@xensource.com>
handle on appropriate operations. Next step is to plug this
through to the store daemon and get rid of the nasty serialisation
mutex for transactions.
Signed-off-by: Keir Fraser <keir@xensource.com>
tools. /dev/xen/evtchn is now used by daemons to connect to
remote domains: the advantage is that the local ports are garbage
collected automatically if the daemon dies. xen no longer
constructs end-to-end event-channel port pairs -- it allocates an
unbound port in new domU and writes that port to xenstore. It is
then picked up by teh appropriate daemon which does interdomain bind
via /dev/xen/evtchn.
Signed-off-by: Keir Fraser <keir@xensource.com>
