Commit Graph

109 Commits

Author SHA1 Message Date
Steven Noonan 45e27161c6 xenbus: fix compile failure on ARM with Xen enabled
Adding an include of linux/mm.h resolves this:
	drivers/xen/xenbus/xenbus_client.c: In function ‘xenbus_map_ring_valloc_hvm’:
	drivers/xen/xenbus/xenbus_client.c:532:66: error: implicit declaration of function ‘page_to_section’ [-Werror=implicit-function-declaration]

CC: stable@vger.kernel.org
Signed-off-by: Steven Noonan <steven@uplinklabs.net>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-01 10:55:00 -05:00
Stefano Stabellini 3216dceb31 xen: introduce xen_remap, use it instead of ioremap
ioremap can't be used to map ring pages on ARM because it uses device
memory caching attributes (MT_DEVICE*).

Introduce a Xen specific abstraction to map ring pages, called
xen_remap, that is defined as ioremap on x86 (no behavioral changes).
On ARM it explicitly calls __arm_ioremap with the right caching
attributes: MT_MEMORY.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-02-19 22:02:34 -05:00
Linus Torvalds 896ea17d3d Features:
- Add necessary infrastructure to make balloon driver work under ARM.
  - Add /dev/xen/privcmd interfaces to work with ARM and PVH.
  - Improve Xen PCIBack wild-card parsing.
  - Add Xen ACPI PAD (Processor Aggregator) support - so can offline/online
    sockets depending on the power consumption.
  - PVHVM + kexec = use an E820_RESV region for the shared region so we don't
    overwrite said region during kexec reboot.
  - Cleanups, compile fixes.
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Merge tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen updates from Konrad Rzeszutek Wilk:
 - Add necessary infrastructure to make balloon driver work under ARM.
 - Add /dev/xen/privcmd interfaces to work with ARM and PVH.
 - Improve Xen PCIBack wild-card parsing.
 - Add Xen ACPI PAD (Processor Aggregator) support - so can offline/
   online sockets depending on the power consumption.
 - PVHVM + kexec = use an E820_RESV region for the shared region so we
   don't overwrite said region during kexec reboot.
 - Cleanups, compile fixes.

Fix up some trivial conflicts due to the balloon driver now working on
ARM, and there were changes next to the previous work-arounds that are
now gone.

* tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/PVonHVM: fix compile warning in init_hvm_pv_info
  xen: arm: implement remap interfaces needed for privcmd mappings.
  xen: correctly use xen_pfn_t in remap_domain_mfn_range.
  xen: arm: enable balloon driver
  xen: balloon: allow PVMMU interfaces to be compiled out
  xen: privcmd: support autotranslated physmap guests.
  xen: add pages parameter to xen_remap_domain_mfn_range
  xen/acpi: Move the xen_running_on_version_or_later function.
  xen/xenbus: Remove duplicate inclusion of asm/xen/hypervisor.h
  xen/acpi: Fix compile error by missing decleration for xen_domain.
  xen/acpi: revert pad config check in xen_check_mwait
  xen/acpi: ACPI PAD driver
  xen-pciback: reject out of range inputs
  xen-pciback: simplify and tighten parsing of device IDs
  xen PVonHVM: use E820_Reserved area for shared_info
2012-12-13 14:29:16 -08:00
Sachin Kamat 5af19e475f xen/xenbus: Remove duplicate inclusion of asm/xen/hypervisor.h
asm/xen/hypervisor.h was included twice.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-28 14:39:23 -05:00
Jan Beulich 1bcaba51eb xen/xenbus: fix overflow check in xenbus_file_write()
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
[v1: Rebased on upstream]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30 09:57:49 -04:00
Ian Campbell 7644bdac7f xen: xenbus: quirk uses x86 specific cpuid
This breaks on ARM. This quirk is not necessary on ARM because no
hypervisors of that vintage exist for that architecture (port is too
new).

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[v1: Moved the ifdef inside the function per Jan Beulich suggestion]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-19 15:17:48 -04:00
Konrad Rzeszutek Wilk e9d1aa05da xen/xenbus: Fix compile warning.
We were missing the 'void' on the parameter arguments.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-19 15:17:45 -04:00
Konrad Rzeszutek Wilk cb6b6df111 xen/pv-on-hvm kexec: add quirk for Xen 3.4 and shutdown watches.
The commit 254d1a3f02, titled
"xen/pv-on-hvm kexec: shutdown watches from old kernel" assumes that the
XenBus backend can deal with reading of values from:
 "control/platform-feature-xs_reset_watches":

    ... 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."

Sadly this is not true when using a Xen 3.4 hypervisor and booting a PVHVM
guest. We end up hanging at:

  err = xenbus_scanf(XBT_NIL, "control",
                        "platform-feature-xs_reset_watches", "%d", &supported);

This can easily be seen with guests hanging at xenbus_init:

NX (Execute Disable) protection: active
SMBIOS 2.4 present.
DMI: Xen HVM domU, BIOS 3.4.0 05/13/2011
Hypervisor detected: Xen HVM
Xen version 3.4.
Xen Platform PCI: I/O protocol version 1
... snip ..
calling  xenbus_init+0x0/0x27e @ 1

Reverting the commit or using the attached patch fixes the issue. This fix
checks whether the hypervisor is older than 4.0 and if so does not try to
perform the read.

Fixes-Oracle-Bug: 14708233
CC: stable@vger.kernel.org
Acked-by: Olaf Hering <olaf@aepfle.de>
[v2: Added a comment in the source code]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-12 08:49:21 -04:00
Andres Lagar-Cavilla c571898ffc xen/gndev: Xen backend support for paged out grant targets V4.
Since Xen-4.2, hvm domains may have portions of their memory paged out. When a
foreign domain (such as dom0) attempts to map these frames, the map will
initially fail. The hypervisor returns a suitable errno, and kicks an
asynchronous page-in operation carried out by a helper. The foreign domain is
expected to retry the mapping operation until it eventually succeeds. The
foreign domain is not put to sleep because itself could be the one running the
pager assist (typical scenario for dom0).

This patch adds support for this mechanism for backend drivers using grant
mapping and copying operations. Specifically, this covers the blkback and
gntdev drivers (which map foreign grants), and the netback driver (which copies
foreign grants).

* Add a retry method for grants that fail with GNTST_eagain (i.e. because the
  target foreign frame is paged out).
* Insert hooks with appropriate wrappers in the aforementioned drivers.

The retry loop is only invoked if the grant operation status is GNTST_eagain.
It guarantees to leave a new status code different from GNTST_eagain. Any other
status code results in identical code execution as before.

The retry loop performs 256 attempts with increasing time intervals through a
32 second period. It uses msleep to yield while waiting for the next retry.

V2 after feedback from David Vrabel:
* Explicit MAX_DELAY instead of wrap-around delay into zero
* Abstract GNTST_eagain check into core grant table code for netback module.

V3 after feedback from Ian Campbell:
* Add placeholder in array of grant table error descriptions for unrelated
  error code we jump over.
* Eliminate single map and retry macro in favor of a generic batch flavor.
* Some renaming.
* Bury most implementation in grant_table.c, cleaner interface.

V4 rebased on top of sync of Xen grant table interface headers.

Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
[v5: Fixed whitespace issues]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-21 09:23:51 -04:00
Stefano Stabellini ecc635f90a xen/arm: compile and run xenbus
bind_evtchn_to_irqhandler can legitimately return 0 (irq 0): it is not
an error.

If Linux is running as an HVM domain and is running as Dom0, use
xenstored_local_init to initialize the xenstore page and event channel.

Changes in v4:
- do not xs_reset_watches on dom0.

Changes in v2:
- refactor xenbus_init.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
[v5: Fixed case switch indentations]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-17 10:04:04 -04:00
Konrad Rzeszutek Wilk 25a765b7f0 Merge branch 'x86/platform' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into stable/for-linus-3.7
* 'x86/platform' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (9690 commits)
  x86: Document x86_init.paging.pagetable_init()
  x86: xen: Cleanup and remove x86_init.paging.pagetable_setup_done()
  x86: Move paging_init() call to x86_init.paging.pagetable_init()
  x86: Rename pagetable_setup_start() to pagetable_init()
  x86: Remove base argument from x86_init.paging.pagetable_setup_start
  Linux 3.6-rc5
  HID: tpkbd: work even if the new Lenovo Keyboard driver is not configured
  Remove user-triggerable BUG from mpol_to_str
  xen/pciback: Fix proper FLR steps.
  uml: fix compile error in deliver_alarm()
  dj: memory scribble in logi_dj
  Fix order of arguments to compat_put_time[spec|val]
  xen: Use correct masking in xen_swiotlb_alloc_coherent.
  xen: fix logical error in tlb flushing
  xen/p2m: Fix one-off error in checking the P2M tree directory.
  powerpc: Don't use __put_user() in patch_instruction
  powerpc: Make sure IPI handlers see data written by IPI senders
  powerpc: Restore correct DSCR in context switch
  powerpc: Fix DSCR inheritance in copy_thread()
  powerpc: Keep thread.dscr and thread.dscr_inherit in sync
  ...
2012-09-12 11:14:33 -04:00
Konrad Rzeszutek Wilk b8b0f559c7 xen/apic/xenbus/swiotlb/pcifront/grant/tmem: Make functions or variables static.
There is no need for those functions/variables to be visible. Make them
static and also fix the compile warnings of this sort:

drivers/xen/<some file>.c: warning: symbol '<blah>' was not declared. Should it be static?

Some of them just require including the header file that
declares the functions.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-21 14:50:03 -04:00
Stefano Stabellini 4d9310e397 xen: missing includes
Changes in v2:
- remove pvclock hack;
- remove include linux/types.h from xen/interface/xen.h.
v3:
- Compile under IA64
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-21 14:49:21 -04:00
Olaf Hering 254d1a3f02 xen/pv-on-hvm kexec: shutdown watches from old kernel
Add 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.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-19 15:52:02 -04:00
Linus Torvalds b5f4035adf Features:
* Extend the APIC ops implementation and add IRQ_WORKER vector support so that 'perf' can work properly.
  * Fix self-ballooning code, and balloon logic when booting as initial domain.
  * Move array printing code to generic debugfs
  * Support XenBus domains.
  * Lazily free grants when a domain is dead/non-existent.
  * In M2P code use batching calls
 Bug-fixes:
  * Fix NULL dereference in allocation failure path (hvc_xen)
  * Fix unbinding of IRQ_WORKER vector during vCPU hot-unplug
  * Fix HVM guest resume - we would leak an PIRQ value instead of reusing the existing one.
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Merge tag 'stable/for-linus-3.5-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen updates from Konrad Rzeszutek Wilk:
 "Features:
   * Extend the APIC ops implementation and add IRQ_WORKER vector
     support so that 'perf' can work properly.
   * Fix self-ballooning code, and balloon logic when booting as initial
     domain.
   * Move array printing code to generic debugfs
   * Support XenBus domains.
   * Lazily free grants when a domain is dead/non-existent.
   * In M2P code use batching calls
  Bug-fixes:
   * Fix NULL dereference in allocation failure path (hvc_xen)
   * Fix unbinding of IRQ_WORKER vector during vCPU hot-unplug
   * Fix HVM guest resume - we would leak an PIRQ value instead of
     reusing the existing one."

Fix up add-add onflicts in arch/x86/xen/enlighten.c due to addition of
apic ipi interface next to the new apic_id functions.

* tag 'stable/for-linus-3.5-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: do not map the same GSI twice in PVHVM guests.
  hvc_xen: NULL dereference on allocation failure
  xen: Add selfballoning memory reservation tunable.
  xenbus: Add support for xenbus backend in stub domain
  xen/smp: unbind irqworkX when unplugging vCPUs.
  xen: enter/exit lazy_mmu_mode around m2p_override calls
  xen/acpi/sleep: Enable ACPI sleep via the __acpi_os_prepare_sleep
  xen: implement IRQ_WORK_VECTOR handler
  xen: implement apic ipi interface
  xen/setup: update VA mapping when releasing memory during setup
  xen/setup: Combine the two hypercall functions - since they are quite similar.
  xen/setup: Populate freed MFNs from non-RAM E820 entries and gaps to E820 RAM
  xen/setup: Only print "Freeing XXX-YYY pfn range: Z pages freed" if Z > 0
  xen/gnttab: add deferred freeing logic
  debugfs: Add support to print u32 array in debugfs
  xen/p2m: An early bootup variant of set_phys_to_machine
  xen/p2m: Collapse early_alloc_p2m_middle redundant checks.
  xen/p2m: Allow alloc_p2m_middle to call reserve_brk depending on argument
  xen/p2m: Move code around to allow for better re-usage.
2012-05-24 16:02:08 -07:00
Daniel De Graaf d2fb4c51c7 xenbus: Add support for xenbus backend in stub domain
Add an ioctl to the /dev/xen/xenbus_backend device allowing the xenbus
backend to be started after the kernel has booted. This allows xenstore
to run in a different domain from the dom0.

Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-21 09:53:18 -04:00
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
Linus Torvalds d4c6fa73fe Features:
- PV multiconsole support, so that there can be hvc1, hvc2, etc;
  - 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.
  - 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
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Merge tag 'stable/for-linus-3.4-tag' of 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.
2012-03-22 20:16:14 -07:00
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 bd0d5aa417 xenbus: don't free other end details too early
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>
2012-03-13 14:15:29 -04:00
Jan Beulich 5ac0800143 xenbus: address compiler warnings
- 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>
2012-02-26 11:04:07 -05:00
Jan Beulich a43a5ccdfa xenbus_dev: add missing error check to watch handling
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>
2012-02-03 16:07:05 -05:00
Linus Torvalds 90160371b3 Merge branch 'stable/for-linus-3.3' of 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
  ...
2012-01-10 10:09:59 -08:00
Ian Campbell a800651e88 xen/xenbus: don't reimplement kvasprintf via a fixed size buffer
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>
2012-01-04 17:02:05 -05:00
Ian Campbell 50bf73796e xenbus: maximum buffer size is XENSTORE_PAYLOAD_MAX
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>
2012-01-04 17:02:04 -05:00
Ian Campbell 9e7860cee1 xen/xenbus: Reject replies with payload > XENSTORE_PAYLOAD_MAX.
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>
2012-01-04 17:02:03 -05:00
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
Konrad Rzeszutek Wilk 01464a60a4 xen/xenbus: Fix compile error - missing header for xen_initial_domain()
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>
2011-12-21 14:32:50 -05:00
Daniel De Graaf 2946a52ac7 xenbus: Use grant-table wrapper functions
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>
2011-12-20 17:05:25 -05:00
Daniel De Graaf 2c5d37d30f xenbus: Support HVM backends
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>
2011-12-20 17:02:35 -05:00
Konrad Rzeszutek Wilk cb85f123cd Merge commit 'v3.2-rc3' into stable/for-linus-3.3
* 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()
  ...
2011-12-20 17:01:18 -05:00
Konrad Rzeszutek Wilk b79d2ff98c xen/xenbus-frontend: Fix compile error with randconfig
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>
2011-12-20 10:47:44 -05:00
Konrad Rzeszutek Wilk 12275dd4b7 Revert "xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel"
This reverts commit ddacf5ef68.
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>
2011-12-19 09:30:35 -05:00
Bastian Blank fe7acdbec1 xen/xenbus-frontend: Make error message more clear
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>
2011-12-16 13:29:44 -05:00
Bastian Blank e9f0fec3f5 xen: Add xenbus_backend device
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>
2011-12-16 13:29:41 -05:00
Bastian Blank 2fb3683e7b xen: Add xenbus device driver
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>
2011-12-16 13:29:39 -05:00
David Vrabel cd12909cb5 xen: map foreign pages for shared rings by updating the PTEs directly
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>
2011-11-16 12:13:08 -05:00
Linus Torvalds daedd8708f Merge branch 'stable/cleanups-3.2' of 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}
2011-11-06 20:13:34 -08:00
Linus Torvalds 32aaeffbd4 Merge branch 'modsplit-Oct31_2011' of 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
2011-11-06 19:44:47 -08:00
Linus Torvalds 06d381484f Merge branch 'stable/vmalloc-3.2' of 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()
2011-11-06 18:31:36 -08:00
Paul Gortmaker 63c9744b9a xen: Add export.h for THIS_MODULE/EXPORT_SYMBOL to various xen users.
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>
2011-10-31 19:32:11 -04:00
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
Konrad Rzeszutek Wilk d98b15db37 xen/xenbus: Remove the unnecessary check.
.. 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>
2011-10-19 17:03:29 -04:00
Daniel De Graaf e4184aaf3b xenbus: don't rely on xen_initial_domain to detect local xenstore
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>
2011-10-14 09:25:18 -04:00
Daniel De Graaf 77447991b6 xenbus: Fix loopback event channel assuming domain 0
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>
2011-10-14 09:25:17 -04:00
David Vrabel 4dcaebbf65 xen: use generic functions instead of xen_{alloc, free}_vm_area()
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>
2011-09-29 15:02:18 -04:00
Konrad Rzeszutek Wilk 5b25d89e19 xen/pv-on-hvm:kexec: Fix implicit declaration of function 'xen_hvm_domain'
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>
2011-09-26 13:17:55 -04:00
Olaf Hering ddacf5ef68 xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel
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>
2011-09-22 16:32:24 -04:00
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