linux-stable.git/drivers/hv, branch linux-3.19.y

Drivers: hv: vmbus: Fix a bug in the error path in vmbus_open()

2015-05-06T20:01:59+00:00

commit 40384e4bbeb9f2651fe9bffc0062d9f31ef625bf upstream.

Correctly rollback state if the failure occurs after we have handed over
the ownership of the buffer to the host.

Signed-off-by: K. Y. Srinivasan 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'char-misc-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2014-12-15T00:43:47+00:00

Pull char/misc driver updates from Greg KH:
 "Here's the big char/misc driver update for 3.19-rc1

  Lots of little things all over the place in different drivers, and a
  new subsystem, "coresight" has been added.  Full details are in the
  shortlog"

* tag 'char-misc-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (73 commits)
  parport: parport_pc, do not remove parent devices early
  spmi: Remove shutdown/suspend/resume kernel-doc
  carma-fpga-program: drop videobuf dependency
  carma-fpga: drop videobuf dependency
  carma-fpga-program.c: fix compile errors
  i8k: Fix temperature bug handling in i8k_get_temp()
  cxl: Name interrupts in /proc/interrupt
  CXL: Return error to PSL if IRQ demultiplexing fails & print clearer warning
  coresight-replicator: remove .owner field for driver
  coresight: fixed comments in coresight.h
  coresight: fix typo in comment in coresight-priv.h
  coresight: bindings for coresight drivers
  coresight: Adding ABI documentation
  w1: support auto-load of w1_bq27000 module.
  w1: avoid potential u16 overflow
  cn: verify msg->len before making callback
  mei: export fw status registers through sysfs
  mei: read and print all six FW status registers
  mei: txe: add cherrytrail device id
  mei: kill cached host and me csr values
  ...

hyperv: Add support for vNIC hot removal

2014-12-09T01:24:11+00:00

This patch adds proper handling of the vNIC hot removal event, which includes
a rescind-channel-offer message from the host side that triggers vNIC close and
removal. In this case, the notices to the host during close and removal is not
necessary because the channel is rescinded. This patch blocks these unnecessary
messages, and lets vNIC removal process complete normally.

Signed-off-by: Haiyang Zhang 
Reviewed-by: K. Y. Srinivasan 
Signed-off-by: David S. Miller

hv: hv_balloon: avoid memory leak on alloc_error of 2MB memory block

2014-11-27T03:03:04+00:00

If num_ballooned is not 0, we shouldn't neglect the
already-partially-allocated 2MB memory block(s).

Signed-off-by: Dexuan Cui 
Signed-off-by: K. Y. Srinivasan 
Acked-by: Jason Wang 
Signed-off-by: Greg Kroah-Hartman

Drivers: hv: kvp,vss: Fast propagation of userspace communication failure

2014-11-27T03:00:32+00:00

If we fail to send a message to userspace daemon with cn_netlink_send()
there is no need to wait for userspace to reply as it is not going to
happen. This happens when kvp or vss daemon is stopped after a successful
handshake. Report HV_E_FAIL immediately and cancel the timeout job so
host won't receive two failures.
Use pr_warn() for VSS and pr_debug() for KVP deliberately as VSS request
are rare and result in a failed backup. KVP requests are much more frequent
after a successful handshake so avoid flooding logs. It would be nice to
have an ability to de-negotiate with the host in case userspace daemon gets
disconnected so we won't receive new requests. But I'm not sure it is
possible.

Signed-off-by: Vitaly Kuznetsov 
Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vss: Introduce timeout for communication with userspace

2014-11-27T03:00:32+00:00

In contrast with KVP there is no timeout when communicating with
userspace VSS daemon. In case it gets stuck performing freeze/thaw
operation no message will be sent to the host so it will take very
long (around 10 minutes) before backup fails. Introduce 10 second
timeout using schedule_delayed_work().

Signed-off-by: Vitaly Kuznetsov 
Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: Fix a race condition when unregistering a device

2014-11-07T18:21:44+00:00

When build with Debug the following crash is sometimes observed:
Call Trace:
 [] string+0x40/0x100
 [] vsnprintf+0x218/0x5e0
 [] ? trace_hardirqs_off+0xd/0x10
 [] vscnprintf+0x11/0x30
 [] vprintk+0xd0/0x5c0
 [] ? vmbus_process_rescind_offer+0x0/0x110 [hv_vmbus]
 [] printk+0x41/0x45
 [] vmbus_device_unregister+0x2c/0x40 [hv_vmbus]
 [] vmbus_process_rescind_offer+0x2b/0x110 [hv_vmbus]
...

This happens due to the following race: between 'if (channel->device_obj)' check
in vmbus_process_rescind_offer() and pr_debug() in vmbus_device_unregister() the
device can disappear. Fix the issue by taking an additional reference to the
device before proceeding to vmbus_device_unregister().

Signed-off-by: Vitaly Kuznetsov 
Signed-off-by: K. Y. Srinivasan 
Cc: 
Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: Enable interrupt driven flow control

2014-09-24T06:31:22+00:00

In win8 we have a feature that allows for interrupt driven flow management
for host/guest communication. For instance, if the host were blocked because
there was no space available in the ringbuffer, the host could request that the
guest send an interrupt when space becomes available in the ringbuffer (when
the guest drains the ringbuffer).

While this feature was implemented in the guest a while ago, we had not
advertised that the guest supported this feature. This patch advertises
the support to the host.

For pre-win8 hosts, this has no effect since the size of the ringbuffer
control structure has not changed and all changes have been backward
compatible - unused/reserved space has been used to implement this
feature.

In this version of the patch I have cleaned up the commit log based on
feedback from Greg KH.

Signed-off-by: K. Y. Srinivasan 
Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: Properly protect calls to smp_processor_id()

2014-09-24T06:31:21+00:00

Disable preemption when sampling current processor ID when preemption
is otherwise possible.

Signed-off-by: K. Y. Srinivasan 
Tested-by: Sitsofe Wheeler 
Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: Cleanup hv_post_message()

2014-09-24T06:31:21+00:00

Minimize failures in this function by pre-allocating the buffer
for posting messages. The hypercall for posting the message can fail
for a number of reasons:

        1. Transient resource related issues
        2. Buffer alignment
        3. Buffer cannot span a page boundry

We address issues 2 and 3 by preallocating a per-cpu page for the buffer.
Transient resource related failures are handled by retrying by the callers
of this function.

This patch is based on the investigation
done by Dexuan Cui .

I would like to thank Sitsofe Wheeler 
for reporting the issue and helping in debuggging.

Signed-off-by: K. Y. Srinivasan 
Reported-by: Sitsofe Wheeler 
Cc: 
Tested-by: Sitsofe Wheeler 
Signed-off-by: Greg Kroah-Hartman