linux-stable.git/drivers/xen, branch linux-3.14.y

xen/pciback: Fix conf_space read/write overlap check.

2016-08-10T08:21:02+00:00

commit 02ef871ecac290919ea0c783d05da7eedeffc10e upstream.

Current overlap check is evaluating to false a case where a filter
field is fully contained (proper subset) of a r/w request.  This
change applies classical overlap check instead to include all the
scenarios.

More specifically, for (Hilscher GmbH CIFX 50E-DP(M/S)) device driver
the logic is such that the entire confspace is read and written in 4
byte chunks. In this case as an example, CACHE_LINE_SIZE,
LATENCY_TIMER and PCI_BIST are arriving together in one call to
xen_pcibk_config_write() with offset == 0xc and size == 4.  With the
exsisting overlap check the LATENCY_TIMER field (offset == 0xd, length
== 1) is fully contained in the write request and hence is excluded
from write, which is incorrect.

Signed-off-by: Andrey Grodzovsky 
Reviewed-by: Boris Ostrovsky 
Reviewed-by: Jan Beulich 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

xen/acpi: allow xen-acpi-processor driver to load on Xen 4.7

2016-07-27T16:55:51+00:00

commit 6f2d9d99213514360034c6d52d2c3919290b3504 upstream.

As of Xen 4.7 PV CPUID doesn't expose either of CPUID[1].ECX[7] and
CPUID[0x80000007].EDX[7] anymore, causing the driver to fail to load on
both Intel and AMD systems. Doing any kind of hardware capability
checks in the driver as a prerequisite was wrong anyway: With the
hypervisor being in charge, all such checking should be done by it. If
ACPI data gets uploaded despite some missing capability, the hypervisor
is free to ignore part or all of that data.

Ditch the entire check_prereq() function, and do the only valid check
(xen_initial_domain()) in the caller in its place.

Signed-off-by: Jan Beulich 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

xen/events: Don't move disabled irqs

2016-06-08T00:21:58+00:00

commit f0f393877c71ad227d36705d61d1e4062bc29cf5 upstream.

Commit ff1e22e7a638 ("xen/events: Mask a moving irq") open-coded
irq_move_irq() but left out checking if the IRQ is disabled. This broke
resuming from suspend since it tries to move a (disabled) irq without
holding the IRQ's desc->lock. Fix it by adding in a check for disabled
IRQs.

The resulting stacktrace was:
kernel BUG at /build/linux-UbQGH5/linux-4.4.0/kernel/irq/migration.c:31!
invalid opcode: 0000 [#1] SMP
Modules linked in: xenfs xen_privcmd ...
CPU: 0 PID: 9 Comm: migration/0 Not tainted 4.4.0-22-generic #39-Ubuntu
Hardware name: Xen HVM domU, BIOS 4.6.1-xs125180 05/04/2016
task: ffff88003d75ee00 ti: ffff88003d7bc000 task.ti: ffff88003d7bc000
RIP: 0010:[]  [] irq_move_masked_irq+0xd2/0xe0
RSP: 0018:ffff88003d7bfc50  EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff88003d40ba00 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000100 RDI: ffff88003d40bad8
RBP: ffff88003d7bfc68 R08: 0000000000000000 R09: ffff88003d000000
R10: 0000000000000000 R11: 000000000000023c R12: ffff88003d40bad0
R13: ffffffff81f3a4a0 R14: 0000000000000010 R15: 00000000ffffffff
FS:  0000000000000000(0000) GS:ffff88003da00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd4264de624 CR3: 0000000037922000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff88003d40ba38 0000000000000024 0000000000000000 ffff88003d7bfca0
 ffffffff814c8d92 00000010813ef89d 00000000805ea732 0000000000000009
 0000000000000024 ffff88003cc39b80 ffff88003d7bfce0 ffffffff814c8f66
Call Trace:
 [] eoi_pirq+0xb2/0xf0
 [] __startup_pirq+0xe6/0x150
 [] xen_irq_resume+0x319/0x360
 [] xen_suspend+0xb5/0x180
 [] multi_cpu_stop+0xb5/0xe0
 [] ? cpu_stop_queue_work+0x80/0x80
 [] cpu_stopper_thread+0xb0/0x140
 [] ? finish_task_switch+0x76/0x220
 [] ? __raw_callee_save___pv_queued_spin_unlock+0x11/0x20
 [] smpboot_thread_fn+0x105/0x160
 [] ? sort_range+0x30/0x30
 [] kthread+0xd8/0xf0
 [] ? kthread_create_on_node+0x1e0/0x1e0
 [] ret_from_fork+0x3f/0x70
 [] ? kthread_create_on_node+0x1e0/0x1e0

Signed-off-by: Ross Lagerwall 
Reviewed-by: Boris Ostrovsky 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

xen/events: Mask a moving irq

2016-04-20T06:40:40+00:00

commit ff1e22e7a638a0782f54f81a6c9cb139aca2da35 upstream.

Moving an unmasked irq may result in irq handler being invoked on both
source and target CPUs.

With 2-level this can happen as follows:

On source CPU:
        evtchn_2l_handle_events() ->
            generic_handle_irq() ->
                handle_edge_irq() ->
                   eoi_pirq():
                       irq_move_irq(data);

                       /***** WE ARE HERE *****/

                       if (VALID_EVTCHN(evtchn))
                           clear_evtchn(evtchn);

If at this moment target processor is handling an unrelated event in
evtchn_2l_handle_events()'s loop it may pick up our event since target's
cpu_evtchn_mask claims that this event belongs to it *and* the event is
unmasked and still pending. At the same time, source CPU will continue
executing its own handle_edge_irq().

With FIFO interrupt the scenario is similar: irq_move_irq() may result
in a EVTCHNOP_unmask hypercall which, in turn, may make the event
pending on the target CPU.

We can avoid this situation by moving and clearing the event while
keeping event masked.

Signed-off-by: Boris Ostrovsky 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

xen/gntdev: Grant maps should not be subject to NUMA balancing

2016-01-29T05:57:04+00:00

commit 9c17d96500f78d7ecdb71ca6942830158bc75a2b upstream.

Doing so will cause the grant to be unmapped and then, during
fault handling, the fault to be mistakenly treated as NUMA hint
fault.

In addition, even if those maps could partcipate in NUMA
balancing, it wouldn't provide any benefit since we are unable
to determine physical page's node (even if/when VNUMA is
implemented).

Marking grant maps' VMAs as VM_IO will exclude them from being
part of NUMA balancing.

Signed-off-by: Boris Ostrovsky 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

xen/gntdev: convert priv->lock to a mutex

2015-10-01T09:36:15+00:00

commit 1401c00e59ea021c575f74612fe2dbba36d6a4ee upstream.

Unmapping may require sleeping and we unmap while holding priv->lock, so
convert it to a mutex.

Signed-off-by: David Vrabel 
Reviewed-by: Stefano Stabellini 
Cc: Ian Campbell 
Signed-off-by: Greg Kroah-Hartman

xen/gntdevt: Fix race condition in gntdev_release()

2015-08-17T03:51:49+00:00

commit 30b03d05e07467b8c6ec683ea96b5bffcbcd3931 upstream.

While gntdev_release() is called the MMU notifier is still registered
and can traverse priv->maps list even if no pages are mapped (which is
the case -- gntdev_release() is called after all). But
gntdev_release() will clear that list, so make sure that only one of
those things happens at the same time.

Signed-off-by: Marek Marczykowski-Górecki 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

xen/events: don't bind non-percpu VIRQs with percpu chip

2015-06-06T15:19:32+00:00

commit 77bb3dfdc0d554befad58fdefbc41be5bc3ed38a upstream.

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: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

xen/events: Set irq_info->evtchn before binding the channel to CPU in __startup_pirq()

2015-05-17T16:53:49+00:00

commit 16e6bd5970c88a2ac018b84a5f1dd5c2ff1fdf2c upstream.

.. 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: Boris Ostrovsky 
Tested-by: Annie Li 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

xen/events: Clear cpu_evtchn_mask before resuming

2015-05-17T16:53:49+00:00

commit 5cec98834989a014a9560b1841649eaca95cf00e upstream.

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: Boris Ostrovsky 
Reported-by: Annie Li 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman