Commit Graph

15 Commits

Author SHA1 Message Date
Konrad Rzeszutek Wilk 3066616ce2 xen/xenbus: Add quirk to deal with misconfigured backends.
A rather annoying and common case is when booting a PVonHVM guest
and exposing the PV KBD and PV VFB - as broken toolstacks don't
always initialize the backends correctly.

Normally The HVM guest is using the VGA driver and the emulated
keyboard for this (though upstream version of QEMU implements
PV KBD, but still uses a VGA driver). We provide a very basic
two-stage wait mechanism - where we wait for 30 seconds for all
devices, and then for 270 for all them except the two mentioned.

That allows us to wait for the essential devices, like network
or disk for the full 6 minutes.

To trigger this, put this in your guest config:

vfb = [ 'vnc=1, vnclisten=0.0.0.0 ,vncunused=1']

instead of this:
vnc=1
vnclisten="0.0.0.0"

CC: stable@kernel.org
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
[v3: Split delay in non-essential (30 seconds) and essential
 devices per Ian and Stefano suggestion]
[v4: Added comments per Stefano suggestion]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-19 12:45:01 -04:00
Stefano Stabellini 42c46e6ba5 xen/xenbus: ignore console/0
Unfortunately xend creates a bogus console/0 frotend/backend entry pair
on xenstore that console backends cannot properly cope with.
Any guest behavior that is not completely ignoring console/0 is going
to either cause problems with xenconsoled or qemu.
Returning 0 or -ENODEV from xencons_probe is not enough because it is
going to cause the frontend state to become 4 or 6 respectively.
The best possible thing we can do here is just ignore the entry from
xenbus_probe_frontend.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-13 19:24:52 -04:00
Jan Beulich 73db144b58 Xen: consolidate and simplify struct xenbus_driver instantiation
The 'name', 'owner', and 'mod_name' members are redundant with the
identically named fields in the 'driver' sub-structure. Rather than
switching each instance to specify these fields explicitly, introduce
a macro to simplify this.

Eliminate further redundancy by allowing the drvname argument to
DEFINE_XENBUS_DRIVER() to be blank (in which case the first entry from
the ID table will be used for .driver.name).

Also eliminate the questionable xenbus_register_{back,front}end()
wrappers - their sole remaining purpose was the checking of the
'owner' field, proper setting of which shouldn't be an issue anymore
when the macro gets used.

v2: Restore DRV_NAME for the driver name in xen-pciback.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-04 17:01:17 -05:00
Paul Gortmaker 72ee5112a0 xen: Add module.h to modular drivers/xen users.
Previously these drivers just got module.h implicitly, but we
are cleaning that up and it will be no longer.  Call out the
real users of it.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:32:11 -04:00
Linus Torvalds 04a8752485 Merge branches 'stable/drivers-3.2', 'stable/drivers.bugfixes-3.2' and 'stable/pci.fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/drivers-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xenbus: don't rely on xen_initial_domain to detect local xenstore
  xenbus: Fix loopback event channel assuming domain 0
  xen/pv-on-hvm:kexec: Fix implicit declaration of function 'xen_hvm_domain'
  xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel
  xen/pv-on-hvm kexec: update xs_wire.h:xsd_sockmsg_type from xen-unstable
  xen/pv-on-hvm kexec+kdump: reset PV devices in kexec or crash kernel
  xen/pv-on-hvm kexec: rebind virqs to existing eventchannel ports
  xen/pv-on-hvm kexec: prevent crash in xenwatch_thread() when stale watch events arrive

* 'stable/drivers.bugfixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/pciback: Check if the device is found instead of blindly assuming so.
  xen/pciback: Do not dereference psdev during printk when it is NULL.
  xen: remove XEN_PLATFORM_PCI config option
  xen: XEN_PVHVM depends on PCI
  xen/pciback: double lock typo
  xen/pciback: use mutex rather than spinlock in vpci backend
  xen/pciback: Use mutexes when working with Xenbus state transitions.
  xen/pciback: miscellaneous adjustments
  xen/pciback: use mutex rather than spinlock in passthrough backend
  xen/pciback: use resource_size()

* 'stable/pci.fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/pci: support multi-segment systems
  xen-swiotlb: When doing coherent alloc/dealloc check before swizzling the MFNs.
  xen/pci: make bus notifier handler return sane values
  xen-swiotlb: fix printk and panic args
  xen-swiotlb: Fix wrong panic.
  xen-swiotlb: Retry up three times to allocate Xen-SWIOTLB
  xen-pcifront: Update warning comment to use 'e820_host' option.
2011-10-25 09:19:36 +02:00
Olaf Hering 116df6f004 xen/pv-on-hvm kexec+kdump: reset PV devices in kexec or crash kernel
After triggering a crash dump in a HVM guest, the PV backend drivers
will remain in Connected state. When the kdump kernel starts the PV
drivers will skip such devices. As a result, no root device is found and
the vmcore cant be saved.

A similar situation happens after a kexec boot, here the devices will be
in the Closed state.

With this change all frontend devices with state XenbusStateConnected or
XenbusStateClosed will be reset by changing the state file to Closing ->
Closed -> Initializing.  This will trigger a disconnect in the backend
drivers. Now the frontend drivers will find the backend drivers in state
Initwait and can connect.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
[v2:
  - add timeout when waiting for backend state change
  (based on feedback from Ian Campell)
  - extent printk message to include backend string
  - add comment to fall-through case in xenbus_reset_frontend]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-09-01 11:49:03 -04:00
Bastian Blank cc85e93342 xen: Populate xenbus device attributes
The xenbus bus type uses device_create_file to assign all used device
attributes. However it does not remove them when the device goes away.

This patch uses the dev_attrs field of the bus type to specify default
attributes for all devices.

Signed-off-by: Bastian Blank <waldi@debian.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-06-30 12:15:29 -04:00
Shriram Rajagopalan b3e96c0c75 xen: use freeze/restore/thaw PM events for suspend/resume/chkpt
Use PM_FREEZE, PM_THAW and PM_RESTORE power events for
suspend/resume/checkpoint functionality, instead of PM_SUSPEND
and PM_RESUME. Use of these pm events fixes the Xen Guest hangup
when taking checkpoints. When a suspend event is cancelled
(while taking checkpoints once/continuously), we use PM_THAW
instead of PM_RESUME. PM_RESTORE is used when suspend is not
cancelled. See Documentation/power/devices.txt and linux/pm.h
for more info about freeze, thaw and restore. The sequence of
pm events in a suspend-resume scenario is shown below.

        dpm_suspend_start(PMSG_FREEZE);

                dpm_suspend_noirq(PMSG_FREEZE);

                       sysdev_suspend(PMSG_FREEZE);
                       cancelled = suspend_hypercall()
                       sysdev_resume();

               dpm_resume_noirq(cancelled ? PMSG_THAW : PMSG_RESTORE);

       dpm_resume_end(cancelled ? PMSG_THAW : PMSG_RESTORE);

Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-16 13:42:56 -04:00
Kazuhiro SUZUKI c7853aea57 xen: xenbus PM events support
Make xenbus frontend device subscribe to PM events
to receive suspend/resume/freeze/thaw/restore
notifications.

Signed-off-by: Kenji Wakamiya <wkenji@jp.fujitsu.com>
Signed-off-by: Kazuhiro Suzuki <kaz@jp.fujitsu.com>
Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
[shriram--minor mods and improved commit message]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-16 13:06:29 -04:00
Ian Campbell 6bac7f9f9e xen/xenbus: fixup checkpatch issues in xenbus_probe*
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05 16:31:08 -05:00
Jeremy Fitzhardinge 0ff4fdf065 xen/xenbus: clean up noise in xenbus_probe_frontend.c
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to 616ff7a06a3f in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05 16:30:56 -05:00
Jeremy Fitzhardinge 1b31a14345 xen/xenbus: make frontend bus GPL
Make sure frontend xenbus has a GPL module license, so it can access
all the xenbus symbols exported GPL only.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to 525cbc8adcb5 in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05 16:30:31 -05:00
Jeremy Fitzhardinge 806f5463d2 xenbus/frontend: register bus earlier
Impact: bugfix

Make sure the frontend bus is registered early, before
any drivers want to attach.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to 1d5df318f87f in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05 16:30:18 -05:00
Ian Campbell df660251eb xen: add backend driver support
Impact: backend device support

Add the basic machinery to support backend drivers.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
[corresponds to 79727b851bac in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05 16:29:58 -05:00
Ian Campbell 2de06cc1f1 xen: separate out frontend xenbus
Impact: refactor

Make a distinct frontend xenbus, in preparation for adding a backend xenbus.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
[corresponds to 2fd433a4188f in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git
 with adjustments to reflect changes in the code which is moved]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05 16:29:17 -05:00