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2012-04-19xen/xenbus: Add quirk to deal with misconfigured backends.Konrad Rzeszutek Wilk
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>
2012-03-22Merge tag 'stable/for-linus-3.4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull xen updates from Konrad Rzeszutek Wilk: "which has three neat features: - PV multiconsole support, so that there can be hvc1, hvc2, etc; This can be used in HVM and in PV mode. - P-state and C-state power management driver that uploads said power management data to the hypervisor. It also inhibits cpufreq scaling drivers to load so that only the hypervisor can make power management decisions - fixing a weird perf bug. There is one thing in the Kconfig that you won't like: "default y if (X86_ACPI_CPUFREQ = y || X86_POWERNOW_K8 = y)" (note, that it all depends on CONFIG_XEN which depends on CONFIG_PARAVIRT which by default is off). I've a fix to convert that boolean expression into "default m" which I am going to post after the cpufreq git pull - as the two patches to make this work depend on a fix in Dave Jones's tree. - Function Level Reset (FLR) support in the Xen PCI backend. Fixes: - Kconfig dependencies for Xen PV keyboard and video - Compile warnings and constify fixes - Change over to use percpu_xxx instead of this_cpu_xxx" Fix up trivial conflicts in drivers/tty/hvc/hvc_xen.c due to changes to a removed commit. * tag 'stable/for-linus-3.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen kconfig: relax INPUT_XEN_KBDDEV_FRONTEND deps xen/acpi-processor: C and P-state driver that uploads said data to hypervisor. xen: constify all instances of "struct attribute_group" xen/xenbus: ignore console/0 hvc_xen: introduce HVC_XEN_FRONTEND hvc_xen: implement multiconsole support hvc_xen: support PV on HVM consoles xenbus: don't free other end details too early xen/enlighten: Expose MWAIT and MWAIT_LEAF if hypervisor OKs it. xen/setup/pm/acpi: Remove the call to boot_option_idle_override. xenbus: address compiler warnings xen: use this_cpu_xxx replace percpu_xxx funcs xen/pciback: Support pci_reset_function, aka FLR or D3 support. pci: Introduce __pci_reset_function_locked to be used when holding device_lock. xen: Utilize the restore_msi_irqs hook.
2012-03-13xen/xenbus: ignore console/0Stefano Stabellini
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>
2012-03-13xenbus: don't free other end details too earlyJan Beulich
The individual drivers' remove functions could legitimately attempt to access this information (for logging messages if nothing else). Note that I did not in fact observe a problem anywhere, but I came across this while looking into the reasons for what turned out to need the fix at https://lkml.org/lkml/2012/3/5/336 to vsprintf(). Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-02-26xenbus: address compiler warningsJan Beulich
- casting pointers to integer types of different size is being warned on - an uninitialized variable warning occurred on certain gcc versions Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-02-03xenbus_dev: add missing error check to watch handlingJan Beulich
So far only the watch path was checked to be zero terminated, while the watch token was merely assumed to be. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-10Merge branch 'stable/for-linus-3.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/for-linus-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (37 commits) xen/pciback: Expand the warning message to include domain id. xen/pciback: Fix "device has been assigned to X domain!" warning xen/pciback: Move the PCI_DEV_FLAGS_ASSIGNED ops to the "[un|]bind" xen/xenbus: don't reimplement kvasprintf via a fixed size buffer xenbus: maximum buffer size is XENSTORE_PAYLOAD_MAX xen/xenbus: Reject replies with payload > XENSTORE_PAYLOAD_MAX. Xen: consolidate and simplify struct xenbus_driver instantiation xen-gntalloc: introduce missing kfree xen/xenbus: Fix compile error - missing header for xen_initial_domain() xen/netback: Enable netback on HVM guests xen/grant-table: Support mappings required by blkback xenbus: Use grant-table wrapper functions xenbus: Support HVM backends xen/xenbus-frontend: Fix compile error with randconfig xen/xenbus-frontend: Make error message more clear xen/privcmd: Remove unused support for arch specific privcmp mmap xen: Add xenbus_backend device xen: Add xenbus device driver xen: Add privcmd device driver xen/gntalloc: fix reference counts on multi-page mappings ...
2012-01-04xen/xenbus: don't reimplement kvasprintf via a fixed size bufferIan Campbell
Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Cc: Haogang Chen <haogangchen@gmail.com> Acked-by: Jan Beulich <JBeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-04xenbus: maximum buffer size is XENSTORE_PAYLOAD_MAXIan Campbell
Use this now that it is defined even though it happens to be == PAGE_SIZE. The code which takes requests from userspace already validates against the size of this buffer so no further checks are required to ensure that userspace requests comply with the protocol in this respect. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Cc: Haogang Chen <haogangchen@gmail.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-04xen/xenbus: Reject replies with payload > XENSTORE_PAYLOAD_MAX.Ian Campbell
Haogang Chen found out that: There is a potential integer overflow in process_msg() that could result in cross-domain attack. body = kmalloc(msg->hdr.len + 1, GFP_NOIO | __GFP_HIGH); When a malicious guest passes 0xffffffff in msg->hdr.len, the subsequent call to xb_read() would write to a zero-length buffer. The other end of this connection is always the xenstore backend daemon so there is no guest (malicious or otherwise) which can do this. The xenstore daemon is a trusted component in the system. However this seem like a reasonable robustness improvement so we should have it. And Ian when read the API docs found that: The payload length (len field of the header) is limited to 4096 (XENSTORE_PAYLOAD_MAX) in both directions. If a client exceeds the limit, its xenstored connection will be immediately killed by xenstored, which is usually catastrophic from the client's point of view. Clients (particularly domains, which cannot just reconnect) should avoid this. so this patch checks against that instead. This also avoids a potential integer overflow pointed out by Haogang Chen. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Cc: Haogang Chen <haogangchen@gmail.com> CC: stable@kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-04Xen: consolidate and simplify struct xenbus_driver instantiationJan Beulich
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>
2011-12-21xen/xenbus: Fix compile error - missing header for xen_initial_domain()Konrad Rzeszutek Wilk
drivers/xen/xenbus/xenbus_dev_backend.c:74:2: error: implicit declaration of function 'xen_initial_domain' Reported-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-12-20xenbus: Use grant-table wrapper functionsDaniel De Graaf
For xenbus_{map,unmap}_ring to work on HVM, the grant table operations must be set up using the gnttab_set_{map,unmap}_op functions instead of directly populating the fields of gnttab_map_grant_ref. These functions simply populate the structure on paravirtualized Xen; however, on HVM they must call __pa() on vaddr when populating op->host_addr because the hypervisor cannot directly interpret guest-virtual addresses. Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov> [v1: Fixed cleanpatch error] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-12-20xenbus: Support HVM backendsDaniel De Graaf
Add HVM implementations of xenbus_(map,unmap)_ring_v(alloc,free) so that ring mappings can be done without using GNTMAP_contains_pte which is not supported on HVM. This also removes the need to use vmlist_lock on PV by tracking the allocated xenbus rings. Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov> [v1: Fix compile error when XENBUS_FRONTEND is defined as module] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-12-20Merge commit 'v3.2-rc3' into stable/for-linus-3.3Konrad Rzeszutek Wilk
* commit 'v3.2-rc3': (412 commits) Linux 3.2-rc3 virtio-pci: make reset operation safer virtio-mmio: Correct the name of the guest features selector virtio: add HAS_IOMEM dependency to MMIO platform bus driver eCryptfs: Extend array bounds for all filename chars eCryptfs: Flush file in vma close eCryptfs: Prevent file create race condition regulator: TPS65910: Fix VDD1/2 voltage selector count i2c: Make i2cdev_notifier_call static i2c: Delete ANY_I2C_BUS i2c: Fix device name for 10-bit slave address i2c-algo-bit: Generate correct i2c address sequence for 10-bit target drm: integer overflow in drm_mode_dirtyfb_ioctl() Revert "of/irq: of_irq_find_parent: check for parent equal to child" drivers/gpu/vga/vgaarb.c: add missing kfree drm/radeon/kms/atom: unify i2c gpio table handling drm/radeon/kms: fix up gpio i2c mask bits for r4xx for real ttm: Don't return the bo reserved on error path mount_subtree() pointless use-after-free iio: fix a leak due to improper use of anon_inode_getfd() ...
2011-12-20xen/xenbus-frontend: Fix compile error with randconfigKonrad Rzeszutek Wilk
drivers/xen/xenbus/xenbus_dev_frontend.c: In function 'xenbus_init': drivers/xen/xenbus/xenbus_dev_frontend.c:609:2: error: implicit declaration of function 'xen_domain' Reported-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-12-19Revert "xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from ↵Konrad Rzeszutek Wilk
old kernel" This reverts commit ddacf5ef684a655abe2bb50c4b2a5b72ae0d5e05. As when booting the kernel under Amazon EC2 as an HVM guest it ends up hanging during startup. Reverting this we loose the fix for kexec booting to the crash kernels. Fixes Canonical BZ #901305 (http://bugs.launchpad.net/bugs/901305) Tested-by: Alessandro Salvatori <sandr8@gmail.com> Reported-by: Stefan Bader <stefan.bader@canonical.com> Acked-by: Ian Campbell <Ian.Campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-12-16xen/xenbus-frontend: Make error message more clearBastian Blank
Add the work frontend to the error message because we now also have a backend device. 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>
2011-12-16xen: Add xenbus_backend deviceBastian Blank
Access for xenstored to the event channel and pre-allocated ring is managed via xenfs. This adds its own character device featuring mmap for the ring and an ioctl for the event channel. 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>
2011-12-16xen: Add xenbus device driverBastian Blank
Access to xenbus is currently handled via xenfs. This adds a device driver for xenbus and makes xenfs use this code. 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>
2011-11-16xen: map foreign pages for shared rings by updating the PTEs directlyDavid Vrabel
When mapping a foreign page with xenbus_map_ring_valloc() with the GNTTABOP_map_grant_ref hypercall, set the GNTMAP_contains_pte flag and pass a pointer to the PTE (in init_mm). After the page is mapped, the usual fault mechanism can be used to update additional MMs. This allows the vmalloc_sync_all() to be removed from alloc_vm_area(). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> [v1: Squashed fix by Michal for no-mmu case] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Michal Simek <monstr@monstr.eu>
2011-11-06Merge branch 'stable/cleanups-3.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/cleanups-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: use static initializers in xen-balloon.c Xen: fix braces and tabs coding style issue in xenbus_probe.c Xen: fix braces coding style issue in xenbus_probe.h Xen: fix whitespaces,tabs coding style issue in drivers/xen/pci.c Xen: fix braces coding style issue in gntdev.c and grant-table.c Xen: fix whitespaces,tabs coding style issue in drivers/xen/events.c Xen: fix whitespaces,tabs coding style issue in drivers/xen/balloon.c Fix up trivial whitespace-conflicts in drivers/xen/{balloon.c,pci.c,xenbus/xenbus_probe.c}
2011-11-06Merge branch 'modsplit-Oct31_2011' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux * 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits) Revert "tracing: Include module.h in define_trace.h" irq: don't put module.h into irq.h for tracking irqgen modules. bluetooth: macroize two small inlines to avoid module.h ip_vs.h: fix implicit use of module_get/module_put from module.h nf_conntrack.h: fix up fallout from implicit moduleparam.h presence include: replace linux/module.h with "struct module" wherever possible include: convert various register fcns to macros to avoid include chaining crypto.h: remove unused crypto_tfm_alg_modname() inline uwb.h: fix implicit use of asm/page.h for PAGE_SIZE pm_runtime.h: explicitly requires notifier.h linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h miscdevice.h: fix up implicit use of lists and types stop_machine.h: fix implicit use of smp.h for smp_processor_id of: fix implicit use of errno.h in include/linux/of.h of_platform.h: delete needless include <linux/module.h> acpi: remove module.h include from platform/aclinux.h miscdevice.h: delete unnecessary inclusion of module.h device_cgroup.h: delete needless include <linux/module.h> net: sch_generic remove redundant use of <linux/module.h> net: inet_timewait_sock doesnt need <linux/module.h> ... Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in - drivers/media/dvb/frontends/dibx000_common.c - drivers/media/video/{mt9m111.c,ov6650.c} - drivers/mfd/ab3550-core.c - include/linux/dmaengine.h
2011-11-06Merge branch 'stable/vmalloc-3.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: net: xen-netback: use API provided by xenbus module to map rings block: xen-blkback: use API provided by xenbus module to map rings xen: use generic functions instead of xen_{alloc, free}_vm_area()
2011-10-31xen: Add export.h for THIS_MODULE/EXPORT_SYMBOL to various xen users.Paul Gortmaker
Things like THIS_MODULE and EXPORT_SYMBOL were simply everywhere because module.h was also everywhere. But we are fixing the latter. So we need to call out the real users in advance. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31xen: Add module.h to modular drivers/xen users.Paul Gortmaker
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>
2011-10-25Merge branches 'stable/drivers-3.2', 'stable/drivers.bugfixes-3.2' and ↵Linus Torvalds
'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.
2011-10-19xen/xenbus: Remove the unnecessary check.Konrad Rzeszutek Wilk
.. we check whether 'xdev' is NULL - but there is no need for it as the 'dev' check is done before. The 'dev' is embedded in the 'xdev' so having xdev != NULL with dev being being checked is not going to happen. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-14xenbus: don't rely on xen_initial_domain to detect local xenstoreDaniel De Graaf
The xenstore daemon does not have to run in the xen initial domain; however, Linux currently uses xen_initial_domain to test if a loopback event channel should be used instead of the event channel provided in Xen's start_info structure. Instead, if the event channel passed in the start_info structure is not valid, assume that this domain will run xenstored locally and set up the event channel. Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov> Reviewed-by: Ian Campbell <Ian.Campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-14xenbus: Fix loopback event channel assuming domain 0Daniel De Graaf
The xenbus event channel established in xenbus_init is intended to be a loopback channel, but the remote domain was hardcoded to 0; this will cause the channel to be unusable when xenstore is not being run in domain 0. Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov> Reviewed-by: Ian Campbell <Ian.Campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-09-29xen: use generic functions instead of xen_{alloc, free}_vm_area()David Vrabel
Replace calls to the Xen-specific xen_alloc_vm_area() and xen_free_vm_area() functions with the generic equivalent (alloc_vm_area() and free_vm_area()). On x86, these were identical already. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-09-26xen/pv-on-hvm:kexec: Fix implicit declaration of function 'xen_hvm_domain'Konrad Rzeszutek Wilk
Randy found a compile error when using make randconfig to trigger drivers/xen/xenbus/xenbus_xs.c:909:2: error: implicit declaration of function 'xen_hvm_domain' it is unclear which of the CONFIG options triggered this. This patch fixes the error. Reported-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-09-22xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernelOlaf Hering
Add new xs_reset_watches function to shutdown watches from old kernel after kexec boot. The old kernel does not unregister all watches in the shutdown path. They are still active, the double registration can not be detected by the new kernel. When the watches fire, unexpected events will arrive and the xenwatch thread will crash (jumps to NULL). An orderly reboot of a hvm guest will destroy the entire guest with all its resources (including the watches) before it is rebuilt from scratch, so the missing unregister is not an issue in that case. With this change the xenstored is instructed to wipe all active watches for the guest. However, a patch for xenstored is required so that it accepts the XS_RESET_WATCHES request from a client (see changeset 23839:42a45baf037d in xen-unstable.hg). Without the patch for xenstored the registration of watches will fail and some features of a PVonHVM guest are not available. The guest is still able to boot, but repeated kexec boots will fail. [v5: use xs_single instead of passing a dummy string to xs_talkv] [v4: ignore -EEXIST in xs_reset_watches] [v3: use XS_RESET_WATCHES instead of XS_INTRODUCE] [v2: move all code which deals with XS_INTRODUCE into xs_introduce() (based on feedback from Ian Campbell); remove casts from kvec assignment] Signed-off-by: Olaf Hering <olaf@aepfle.de> [v1: Redid the git description a bit] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-09-01xen/pv-on-hvm kexec+kdump: reset PV devices in kexec or crash kernelOlaf Hering
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>
2011-09-01xen/pv-on-hvm kexec: prevent crash in xenwatch_thread() when stale watch ↵Olaf Hering
events arrive During repeated kexec boots xenwatch_thread() can crash because xenbus_watch->callback is cleared by xenbus_watch_path() if a node/token combo for a new watch happens to match an already registered watch from an old kernel. In this case xs_watch returns -EEXISTS, then register_xenbus_watch() does not remove the to-be-registered watch from the list of active watches but returns the -EEXISTS to the caller anyway. Because the watch is still active in xenstored it will cause an event which will arrive in the new kernel. process_msg() will find the encapsulated struct xenbus_watch in its list of registered watches and puts the "empty" watch handle in the queue for xenwatch_thread(). xenwatch_thread() then calls ->callback which was cleared earlier by xenbus_watch_path(). To prevent that crash in a guest running on an old xen toolstack remove the special -EEXIST handling. v2: - remove the EEXIST handing in register_xenbus_watch() instead of checking for ->callback in process_msg() Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Olaf Hering <olaf@aepfle.de>
2011-07-26Xen: fix braces and tabs coding style issue in xenbus_probe.cRuslan Pisarev
This is a patch to the xenbus_probe.c file that fixed up braces and tabs errors found by the checkpatch.pl tools. Signed-off-by: Ruslan Pisarev <ruslan@rpisarev.org.ua> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-26Xen: fix braces coding style issue in xenbus_probe.hRuslan Pisarev
This is a patch to the xenbus_probe.h file that fixed up braces errors found by the checkpatch.pl tools. Signed-off-by: Ruslan Pisarev <ruslan@rpisarev.org.ua> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-06-30xen: Add module alias to autoload backend driversBastian Blank
All the Xen backend drivers are assigned to a special bus type xen-backend. This patch exports xen-backend:* names through modalias and uevent to autoload them. 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>
2011-06-30xen: Populate xenbus device attributesBastian Blank
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>
2011-03-16xen: use freeze/restore/thaw PM events for suspend/resume/chkptShriram Rajagopalan
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>
2011-03-16xen: xenbus PM events supportKazuhiro SUZUKI
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>
2011-01-05xen/xenbus: fixup checkpatch issues in xenbus_probe*Ian Campbell
Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xen/xenbus: clean up noise in xenbus_probe_frontend.cJeremy Fitzhardinge
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>
2011-01-05xen/xenbus: clean up noise in xenbus_probe_backend.cJeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ian Campbell <ian.campbell@citrix.com> [corresponds to 98b833aaf81e in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xen/xenbus: clean up noise in xenbus_probe.cJeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ian Campbell <ian.campbell@citrix.com> [corresponds to 01aded30aaef in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xen/xenbus: cleanup debug noise in xenbus_comms.cJeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ian Campbell <ian.campbell@citrix.com> [corresponds to 6796c12281dc in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xen/xenbus: clean up error handlingJeremy Fitzhardinge
Don't report errors when booting on non-Xen, because its just confusing. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ian Campbell <ian.campbell@citrix.com> [corresponds to 8aa08376d6aa in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xen/xenbus: make frontend bus GPLJeremy Fitzhardinge
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>
2011-01-05xen/xenbus: make sure backend bus is registered earlierJeremy Fitzhardinge
Impact: bugfix Need to register it 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 a7a9c3a942c6 in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xenbus/frontend: register bus earlierJeremy Fitzhardinge
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>