SPP was used by the grant table v2 code which has been removed in
commit 438b33c7 "xen/grant-table:
remove support for V2 tables".
Signed-off-by: NJulien Grall <julien.grall@citrix.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

virt_to_mfn should take a void* rather an unsigned long. While it
doesn't really matter now, it would throw a compiler warning later when
virt_to_mfn will enforce the type.

At the same time, avoid to compute new virtual address every time in the
loop and directly increment the parameter as we don't use it later.
Signed-off-by: NJulien Grall <julien.grall@citrix.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Using xen/page.h will be necessary later for using common xen page
helpers.

As xen/page.h already include asm/xen/page.h, always use the later.
Signed-off-by: NJulien Grall <julien.grall@citrix.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: netdev@vger.kernel.org
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Older compilers don't recognize that "v" can't be used uninitialized;
other code using hvm_get_parameter() zeros the value too, so follow
suit here.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

A non-percpu VIRQ (e.g., VIRQ_CONSOLE) may be freed on a different
VCPU than it is bound to.  This can result in a race between
handle_percpu_irq() and removing the action in __free_irq() because
handle_percpu_irq() does not take desc->lock.  The interrupt handler
sees a NULL action and oopses.

Only use the percpu chip/handler for per-CPU VIRQs (like VIRQ_TIMER).

  # cat /proc/interrupts | grep virq
   40:      87246          0  xen-percpu-virq      timer0
   44:          0          0  xen-percpu-virq      debug0
   47:          0      20995  xen-percpu-virq      timer1
   51:          0          0  xen-percpu-virq      debug1
   69:          0          0   xen-dyn-virq      xen-pcpu
   74:          0          0   xen-dyn-virq      mce
   75:         29          0   xen-dyn-virq      hvc_console
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Cc: <stable@vger.kernel.org>

Make sure that xen_swiotlb_init allocates buffers that are DMA capable
when at least one memblock is available below 4G. Otherwise we assume
that all devices on the SoC can cope with >4G addresses. We do this on
ARM and ARM64, where dom0 is mapped 1:1, so pfn == mfn in this case.

No functional changes on x86.

From: Chen Baozi <baozich@gmail.com>
Signed-off-by: NChen Baozi <baozich@gmail.com>
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: NChen Baozi <baozich@gmail.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

.. because bind_evtchn_to_cpu(evtchn, cpu) will map evtchn to
'info' and pass 'info' down to xen_evtchn_port_bind_to_cpu().
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: NAnnie Li <annie.li@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

After a resume the hypervisor/tools may change xenbus event
channel number. We should re-query it.
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

When a guest is resumed, the hypervisor may change event channel
assignments. If this happens and the guest uses 2-level events it
is possible for the interrupt to be claimed by wrong VCPU since
cpu_evtchn_mask bits may be stale. This can happen even though
evtchn_2l_bind_to_cpu() attempts to clear old bits: irq_info that
is passed in is not necessarily the original one (from pre-migration
times) but instead is freshly allocated during resume and so any
information about which CPU the channel was bound to is lost.

Thus we should clear the mask during resume.

We also need to make sure that bits for xenstore and console channels
are set when these two subsystems are resumed. While rebind_evtchn_irq()
(which is invoked for both of them on a resume) calls irq_set_affinity(),
the latter will in fact postpone setting affinity until handling the
interrupt. But because cpu_evtchn_mask will have bits for these two
cleared we won't be able to take the interrupt.

With that in mind, we need to bind those two channels explicitly in
rebind_evtchn_irq(). We will keep irq_set_affinity() so that we have a
pass through generic irq affinity code later, in case something needs
to be updated there as well.

(Also replace cpumask_of(0) with cpumask_of(info->cpu) in
rebind_evtchn_irq(): it should be set to zero in preceding
xen_irq_info_evtchn_setup().)
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Reported-by: NAnnie Li <annie.li@oracle.com>
Cc: <stable@vger.kernel.org> # 3.14+
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

The variable for the 'permissive' module parameter used to be static
but was recently changed to be extern.  This puts it in the kernel
global namespace if the driver is built-in, so its name should begin
with a prefix identifying the driver.
Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Fixes: af6fc858 ("xen-pciback: limit guest control of command register")
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Commit 77e32c89 ("clockevents: Manage device's state separately for
the core") decouples clockevent device's modes from states. With this
change when a Xen guest tries to resume, it won't be calling its
set_mode op which needs to be done on each VCPU in order to make the
hypervisor aware that we are in oneshot mode.

This happens because clockevents_tick_resume() (which is an intermediate
step of resuming ticks on a processor) doesn't call clockevents_set_state()
anymore and because during suspend clockevent devices on all VCPUs (except
for the one doing the suspend) are left in ONESHOT state. As result, during
resume the clockevents state machine will assume that device is already
where it should be and doesn't need to be updated.

To avoid this problem we should suspend ticks on all VCPUs during
suspend.
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

There are several place using gnttab async unmap and wait for
completion, so move the common code to a function
gnttab_unmap_refs_sync().
Signed-off-by: NBob Liu <bob.liu@oracle.com>
Acked-by: NRoger Pau Monné <roger.pau@citrix.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

If the device being added to Xen is not contained in the ACPI table,
walk the PCI device tree to find a parent that is contained in the ACPI
table before finding the PXM information from this device.

Previously, it would try to get a handle for the device, then the
device's bridge, then the physfn.  This changes the order so that it
tries to get a handle for the device, then the physfn, the walks up the
PCI device tree.
Signed-off-by: NRoss Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Originally Xen PV drivers only use single-page ring to pass along
information. This might limit the throughput between frontend and
backend.

The patch extends Xenbus driver to support multi-page ring, which in
general should improve throughput if ring is the bottleneck. Changes to
various frontend / backend to adapt to the new interface are also
included.

Affected Xen drivers:
* blkfront/back
* netfront/back
* pcifront/back
* scsifront/back
* vtpmfront

The interface is documented, as before, in xenbus_client.c.
Signed-off-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NBob Liu <bob.liu@oracle.com>
Cc: Konrad Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Currently, cleancache_register_ops returns the previous value of
cleancache_ops to allow chaining.  However, chaining, as it is
implemented now, is extremely dangerous due to possible pool id
collisions.  Suppose, a new cleancache driver is registered after the
previous one assigned an id to a super block.  If the new driver assigns
the same id to another super block, which is perfectly possible, we will
have two different filesystems using the same id.  No matter if the new
driver implements chaining or not, we are likely to get data corruption
with such a configuration eventually.

This patch therefore disables the ability to override cleancache_ops
altogether as potentially dangerous.  If there is already cleancache
driver registered, all further calls to cleancache_register_ops will
return EBUSY.  Since no user of cleancache implements chaining, we only
need to make minor changes to the code outside the cleancache core.
Signed-off-by: NVladimir Davydov <vdavydov@parallels.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Stefan Hengelein <ilendir@googlemail.com>
Cc: Florian Schmaus <fschmaus@gmail.com>
Cc: Andor Daam <andor.daam@googlemail.com>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: Bob Liu <lliubbo@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Instead of calling target_fabric_configfs_init() +
target_fabric_configfs_register() / target_fabric_configfs_deregister()
target_fabric_configfs_free() from every target driver, rewrite the API
so that we have simple register/unregister functions that operate on
a const operations vector.

This patch also fixes a memory leak in several target drivers. Several
target drivers namely called target_fabric_configfs_deregister()
without calling target_fabric_configfs_free().

A large part of this patch is based on earlier changes from
Bart Van Assche <bart.vanassche@sandisk.com>.

(v2: Add a new TF_CIT_SETUP_DRV macro so that the core configfs code
can declare attributes as either core only or for drivers)
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

When ACPI is enabled on ARM64, XEN ACPI will also compiled
into the kernel, but XEN ACPI is x86 dependent, so introduce
CONFIG_XEN_ACPI to make it depend on x86 before XEN ACPI is
functional on ARM64.

CC: Julien Grall <julien.grall@linaro.org>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: Boris Ostrovsky <boris.ostrovsky@oracle.com>
CC: David Vrabel <david.vrabel@citrix.com>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Commit 25b884a8 ("x86/xen: set
regions above the end of RAM as 1:1") introduced a regression.

To be able to add memory pages which were added via memory hotplug to
a pv domain, the pages must be "invalid" instead of "identity" in the
p2m list before they can be added.
Suggested-by: NDavid Vrabel <david.vrabel@citrix.com>
Signed-off-by: NJuergen Gross <jgross@suse.com>
Cc: <stable@vger.kernel.org> # 3.16+
Reviewed-by: NDaniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Commit 054954eb ("xen: switch to linear
virtual mapped sparse p2m list") introduced a regression regarding to
memory hotplug for a pv-domain: as the virtual space for the p2m list
is allocated for the to be expected memory size of the domain only,
hotplugged memory above that size will not be usable by the domain.

Correct this by using a configurable size for the p2m list in case of
memory hotplug enabled (default supported memory size is 512 GB for
64 bit domains and 4 GB for 32 bit domains).
Signed-off-by: NJuergen Gross <jgross@suse.com>
Cc: <stable@vger.kernel.org> # 3.19+
Reviewed-by: NDaniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

This patch changes loopback, usb-gadget, vhost-scsi and xen-scsiback
fabric code to invoke transport_register_session() instead of the
unprotected flavour, to ensure se_tpg->session_lock is taken when
adding new session list nodes to se_tpg->tpg_sess_list.

Note that since these four fabric drivers already hold their own
internal TPG mutexes when accessing se_tpg->tpg_sess_list, and
consist of a single se_session created through configfs attribute
access, no list corruption can currently occur.

So for correctness sake, go ahead and use the se_tpg->session_lock
protected version for these four fabric drivers.
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

It's not clear to me why only the enabling operation got handled so
far.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

When a xen domain is being restored the LUN state of a pvscsi device
is "Connected" and not "Initialising" as in case of attaching a new
pvscsi LUN.

This must be taken into account when adding a new pvscsi device for
a domain as otherwise the pvscsi LUN won't be connected to the
SCSI target associated with it.
Signed-off-by: NJuergen Gross <jgross@suse.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Add the {xen-pvscsi: } prefix in pr_fmt and remove DPRINTK, then
replace all DPRINTK with pr_debug.

Also fixed up some comments just as eliminate redundant whitespace
and format the code.

These will make the code easier to read.
Signed-off-by: NTao Chen <boby.chen@huawei.com>
Reviewed-by: NJuergen Gross <jgross@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Static checkers complain about the missing call to misc_deregister() if
bind_virq_for_mce() fails.

Also I reversed the tests so that we do error handling instead of
success handling.  That way we just have a series of function calls
instead of the more complicated nested if statements in the original
code.  Let's preserve the error codes as well.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Make the IOCTL_PRIVCMD_MMAPBATCH_V2 (and older V1 version) map
multiple frames at a time rather than one at a time, despite the pages
being non-consecutive GFNs.

xen_remap_foreign_mfn_array() is added which maps an array of GFNs
(instead of a consecutive range of GFNs).

Since per-frame errors are returned in an array, privcmd must set the
MMAPBATCH_V1 error bits as part of the "report errors" phase, after
all the frames are mapped.

Migrate times are significantly improved (when using a PV toolstack
domain).  For example, for an idle 12 GiB PV guest:

        Before     After
  real  0m38.179s  0m26.868s
  user  0m15.096s  0m13.652s
  sys   0m28.988s  0m18.732s
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

Auto-translated physmap guests (arm, arm64 and x86 PVHVM/PVH) map and
unmap foreign GFNs using the same method (updating the physmap).
Unify the two arm and x86 implementations into one commont one.

Note that on arm and arm64, the correct error code will be returned
(instead of always -EFAULT) and map/unmap failure warnings are no
longer printed.  These changes are required if the foreign domain is
paging (-ENOENT failures are expected and must be propagated up to the
caller).
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

We print at the warninig level messages such as:
pciback 0000:90:00.5: MSI-X preparation failed (-38)

which is due to the hypervisor not supporting this sub-hypercall
(which was added in Xen 4.3).

Instead of having scary messages all the time - only have it
when the hypercall is actually supported.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Instead of manual calls of device_create_file(), device_remove_file()
and sysfs_create_group(), assign static attribute groups to the device
to register.  This simplifies the code and avoids possible races.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Instead of manual calls of device_create_file() and
device_remove_file(), assign the static attribute groups to the device
to register.  The conditional build of sysfs is done in is_visible
callback instead.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Otherwise the guest can abuse that control to cause e.g. PCIe
Unsupported Request responses by disabling memory and/or I/O decoding
and subsequently causing (CPU side) accesses to the respective address
ranges, which (depending on system configuration) may be fatal to the
host.

Note that to alter any of the bits collected together as
PCI_COMMAND_GUEST permissive mode is now required to be enabled
globally or on the specific device.

This is CVE-2015-2150 / XSA-120.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Using the pvops kernel a NULL pointer dereference was detected on a
large machine (144 processors) when booting as dom0 in
evtchn_fifo_unmask() during assignment of a pirq.

The event channel in question was the first to need a new entry in
event_array[] in events_fifo.c. Unfortunately xen_irq_info_pirq_setup()
is called with evtchn being 0 for a new pirq and the real event channel
number is assigned to the pirq only during __startup_pirq().

It is mandatory to call xen_evtchn_port_setup() after assigning the
event channel number to the pirq to make sure all memory needed for the
event channel is allocated.
Signed-off-by: NJuergen Gross <jgross@suse.com>
Cc: <stable@vger.kernel.org> # 3.14+
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

A request in the ring buffer mustn't be read after it has been marked
as consumed. Otherwise it might already have been reused by the
frontend without violating the ring protocol.

To avoid inconsistencies in the backend only work on a private copy
of the request. This will ensure a malicious guest not being able to
bypass consistency checks of the backend by modifying an active
request.
Signed-off-by: NJuergen Gross <jgross@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Hypercalls submitted by user space tools via the privcmd driver can
take a long time (potentially many 10s of seconds) if the hypercall
has many sub-operations.

A fully preemptible kernel may deschedule such as task in any upcall
called from a hypercall continuation.

However, in a kernel with voluntary or no preemption, hypercall
continuations in Xen allow event handlers to be run but the task
issuing the hypercall will not be descheduled until the hypercall is
complete and the ioctl returns to user space.  These long running
tasks may also trigger the kernel's soft lockup detection.

Add xen_preemptible_hcall_begin() and xen_preemptible_hcall_end() to
bracket hypercalls that may be preempted.  Use these in the privcmd
driver.

When returning from an upcall, call xen_maybe_preempt_hcall() which
adds a schedule point if if the current task was within a preemptible
hypercall.

Since _cond_resched() can move the task to a different CPU, clear and
set xen_in_preemptible_hcall around the call.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>

Commit 61a734d3 ("xen/manage: Always freeze/thaw processes when
suspend/resuming") ensured that userspace processes were always frozen
before suspending to reduce interaction issues when resuming devices.
However, freeze_processes() does not freeze kernel threads.  Freeze
kernel threads as well to prevent deadlocks with the khubd thread when
resuming devices.

This is what native suspend and resume does.

Example deadlock:
[ 7279.648010]  [<ffffffff81446bde>] ? xen_poll_irq_timeout+0x3e/0x50
[ 7279.648010]  [<ffffffff81448d60>] xen_poll_irq+0x10/0x20
[ 7279.648010]  [<ffffffff81011723>] xen_lock_spinning+0xb3/0x120
[ 7279.648010]  [<ffffffff810115d1>] __raw_callee_save_xen_lock_spinning+0x11/0x20
[ 7279.648010]  [<ffffffff815620b6>] ? usb_control_msg+0xe6/0x120
[ 7279.648010]  [<ffffffff81747e50>] ? _raw_spin_lock_irq+0x50/0x60
[ 7279.648010]  [<ffffffff8174522c>] wait_for_completion+0xac/0x160
[ 7279.648010]  [<ffffffff8109c520>] ? try_to_wake_up+0x2c0/0x2c0
[ 7279.648010]  [<ffffffff814b60f2>] dpm_wait+0x32/0x40
[ 7279.648010]  [<ffffffff814b6eb0>] device_resume+0x90/0x210
[ 7279.648010]  [<ffffffff814b7d71>] dpm_resume+0x121/0x250
[ 7279.648010]  [<ffffffff8144c570>] ? xenbus_dev_request_and_reply+0xc0/0xc0
[ 7279.648010]  [<ffffffff814b80d5>] dpm_resume_end+0x15/0x30
[ 7279.648010]  [<ffffffff81449fba>] do_suspend+0x10a/0x200
[ 7279.648010]  [<ffffffff8144a2f0>] ? xen_pre_suspend+0x20/0x20
[ 7279.648010]  [<ffffffff8144a1d0>] shutdown_handler+0x120/0x150
[ 7279.648010]  [<ffffffff8144c60f>] xenwatch_thread+0x9f/0x160
[ 7279.648010]  [<ffffffff810ac510>] ? finish_wait+0x80/0x80
[ 7279.648010]  [<ffffffff8108d189>] kthread+0xc9/0xe0
[ 7279.648010]  [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80
[ 7279.648010]  [<ffffffff8175087c>] ret_from_fork+0x7c/0xb0
[ 7279.648010]  [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80

[ 7441.216287] INFO: task khubd:89 blocked for more than 120 seconds.
[ 7441.219457]       Tainted: G            X 3.13.11-ckt12.kz #1
[ 7441.222176] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 7441.225827] khubd           D ffff88003f433440     0    89      2 0x00000000
[ 7441.229258]  ffff88003ceb9b98 0000000000000046 ffff88003ce83000 0000000000013440
[ 7441.232959]  ffff88003ceb9fd8 0000000000013440 ffff88003cd13000 ffff88003ce83000
[ 7441.236658]  0000000000000286 ffff88003d3e0000 ffff88003ceb9bd0 00000001001aa01e
[ 7441.240415] Call Trace:
[ 7441.241614]  [<ffffffff817442f9>] schedule+0x29/0x70
[ 7441.243930]  [<ffffffff81743406>] schedule_timeout+0x166/0x2c0
[ 7441.246681]  [<ffffffff81075b80>] ? call_timer_fn+0x110/0x110
[ 7441.249339]  [<ffffffff8174357e>] schedule_timeout_uninterruptible+0x1e/0x20
[ 7441.252644]  [<ffffffff81077710>] msleep+0x20/0x30
[ 7441.254812]  [<ffffffff81555f00>] hub_port_reset+0xf0/0x580
[ 7441.257400]  [<ffffffff81558465>] hub_port_init+0x75/0xb40
[ 7441.259981]  [<ffffffff814bb3c9>] ? update_autosuspend+0x39/0x60
[ 7441.262817]  [<ffffffff814bb4f0>] ? pm_runtime_set_autosuspend_delay+0x50/0xa0
[ 7441.266212]  [<ffffffff8155a64a>] hub_thread+0x71a/0x1750
[ 7441.268728]  [<ffffffff810ac510>] ? finish_wait+0x80/0x80
[ 7441.271272]  [<ffffffff81559f30>] ? usb_port_resume+0x670/0x670
[ 7441.274067]  [<ffffffff8108d189>] kthread+0xc9/0xe0
[ 7441.276305]  [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80
[ 7441.279131]  [<ffffffff8175087c>] ret_from_fork+0x7c/0xb0
[ 7441.281659]  [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80
Signed-off-by: NRoss Lagerwall <ross.lagerwall@citrix.com>
Cc: stable@vger.kernel.org
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

If Xenstore sends back a XS_ERROR for TRANSACTION_END, the driver BUGs
because it cannot find the matching transaction in the list.  For
TRANSACTION_START, it leaks memory.

Check the message as returned from xenbus_dev_request_and_reply(), and
clean up for TRANSACTION_START or discard the error for
TRANSACTION_END.
Signed-off-by: NJennifer Herbert <Jennifer.Herbert@citrix.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

For a PV guest, use the find_special_page op to find the right page.
To handle VMAs being split, remember the start of the original VMA so
the correct index in the pages array can be calculated.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

In an x86 PV guest, get_user_pages_fast() on a userspace address range
containing foreign mappings does not work correctly because the M2P
lookup of the MFN from a userspace PTE may return the wrong page.

Force get_user_pages_fast() to fail on such addresses by marking the PTEs
as special.

If Xen has XENFEAT_gnttab_map_avail_bits (available since at least
4.0), we can do so efficiently in the grant map hypercall.  Otherwise,
it needs to be done afterwards.  This is both inefficient and racy
(the mapping is visible to the task before we fixup the PTEs), but
will be fine for well-behaved applications that do not use the mapping
until after the mmap() system call returns.

Guests with XENFEAT_auto_translated_physmap (ARM and x86 HVM or PVH)
do not need this since get_user_pages() has always worked correctly
for them.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

Use gnttab_unmap_refs_async() to wait until the mapped pages are no
longer in use before unmapping them.

This allows userspace programs to safely use Direct I/O and AIO to a
network filesystem which may retain refs to pages in queued skbs after
the filesystem I/O has completed.
Signed-off-by: NJennifer Herbert <jennifer.herbert@citrix.com>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Unmapping may require sleeping and we unmap while holding priv->lock, so
convert it to a mutex.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>