libxl: fix double free on some config parser errors

If libxlu_cfg_y.y encountered a config file error, the code generated
by bison would sometimes _both_ run the %destructor _and_ call
xlu__cfg_set_store for the same XLU_ConfigSetting* semantic value.
The result would be a double free.

This appears to be because of the use of a mid-rule action.  There is
some discussion of the problems with destructors and mid-rule action
error handling in "(bison)Mid-Rule Actions".  This area is complex and
best avoided.

So fix the bug by abolishing the use of a mid-rule action, which was
in any case not necessary here.

Also while we are there rename the nonterminal rule "setting" to
"assignment", to avoid confusion with the token type "setting", which
had an identically name in a different namespace.  This was especially
confusing because the nonterminal "setting" did not have "setting" as
the type of its semantic value!  (In fact the nonterminal, now called
"assignment", does not have a value so it does not have a value type.)

Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
tmem: add matching unlock for an about-to-be-destroyed object

A 4.2 changeset forces a preempt_disable/enable with
every lock/unlock.

Tmem has dynamically allocated "objects" that contain a
lock.  The lock is held when the object is destroyed.
No reason to unlock something that's about to be destroyed!
But with the preempt_enable/disable in the generic locking code,
and the fact that do_softirq ASSERTs that preempt_count
must be zero, a crash occurs soon after any object is
destroyed.

So force lock to be released before destroying objects.

Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Committed-by: Keir Fraser <keir@xen.org>
nestedsvm: fix interrupt handling

Give the l2 guest a chance to finish the delivery of the last injected
interrupt or exception before we emulate a VMEXIT.
For example after a NPF handled by the host there can be an interrupt
for the l1 guest.

Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
Committed-by: Keir Fraser <keir@xen.org>
x86: comment opaque expression in __page_to_virt()

mm.h's __page_to_virt() has a rather opaque expression. Comment it.

Reported-By: Ian Campbell <ian.campbell@citrix.com>
Suggested-by: Ian Jackson <ian.jackson@eu.citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
x86/HVM: RTC periodic timer emulation adjustments

- don't call rtc_timer_update() on REG_A writes when the value didn't
  change (doing the call always was reported to cause wall clock time
  lagging with the JVM running on Windows)
- don't call rtc_timer_update() on REG_B writes when RTC_PIE didn't
  change

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
make domain_create() return a proper error code

While triggered by the XSA-9 fix, this really is of more general use;
that fix just pointed out very sharply that the current situation
with all domain creation failures reported to user (tools) space as
-ENOMEM is very unfortunate (actively misleading users _and_ support
personnel).

Pull over the pointer <-> error code conversion infrastructure from
Linux, and use it in domain_create() and all it callers.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
libxl/xl: implement support for guest ioport and irq permissions.

This is useful for passing legacy ISA devices (e.g. com ports,
parallel ports) to guests.

Supported syntax is as described in
http://cmrg.fifthhorseman.net/wiki/xen#grantingaccesstoserialhardwaretoadomU

I tested this using Xen's 'q' key handler which prints out the I/O
port and IRQ ranges allowed for each domain. e.g.:

(XEN) Rangesets belonging to domain 31:
(XEN)     I/O Ports  { 2e8-2ef, 2f8-2ff }
(XEN)     Interrupts { 3, 5-6 }

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Tested-by: Dieter Bloms <dieter@bloms.de>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
docs/command line: Clarify the behavior with invalid input.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.de>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
arm: correctly check for error on dom0 allocation

Drop the redundant printk

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jan Beulich <JBeulich@suse.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
libxl: fix api check Makefile

Touch the libxl.api-ok stamp file, and unconditionally put in place
the new _libxl.api-for-check.  This avoids needlessly rerunning the
preprocessor on libxl.h each time we call "make".

Ensure that _libxl.api-for-check gets the CFLAGS used for xl, so that
if it is asked for in a standalone make run it can find xentoollog.h.

Remove *.api-ok on clean.

Also fix .gitignore.

Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
xl.cfg: videoram and stdvga documentation improvements

- videoram: Document that only qemu-xen-traditional device-model currently
   supports changing the amount of video memory for stdvga graphics device.

- videoram: Better document the default amount of videoram for both stdvga
  and Cirrus.

- stdvga: Add a note that stdvga allows bigger amount of videoram and
  bigger resolutions.

Signed-off-by: Pasi K?rkk?inen <pasik@iki.fi>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>