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

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
  ...

1 files changed, 25 insertions, 3 deletions

diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c
index 34f14fddb666..9d5e0d1efdb5 100644
--- a/drivers/hv/hv_snapshot.c
+++ b/drivers/hv/hv_snapshot.c
@@ -28,7 +28,7 @@
 #define VSS_MINOR  0
 #define VSS_VERSION    (VSS_MAJOR << 16 | VSS_MINOR)
 
-
+#define VSS_USERSPACE_TIMEOUT (msecs_to_jiffies(10 * 1000))
 
 /*
  * Global state maintained for transaction that is being processed.
@@ -55,12 +55,24 @@ static const char vss_name[] = "vss_kernel_module";
 static __u8 *recv_buffer;
 
 static void vss_send_op(struct work_struct *dummy);
+static void vss_timeout_func(struct work_struct *dummy);
+
+static DECLARE_DELAYED_WORK(vss_timeout_work, vss_timeout_func);
 static DECLARE_WORK(vss_send_op_work, vss_send_op);
 
 /*
  * Callback when data is received from user mode.
  */
 
+static void vss_timeout_func(struct work_struct *dummy)
+{
+	/*
+	 * Timeout waiting for userspace component to reply happened.
+	 */
+	pr_warn("VSS: timeout waiting for daemon to reply\n");
+	vss_respond_to_host(HV_E_FAIL);
+}
+
 static void
 vss_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
 {
@@ -76,13 +88,15 @@ vss_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
 		return;
 
 	}
-	vss_respond_to_host(vss_msg->error);
+	if (cancel_delayed_work_sync(&vss_timeout_work))
+		vss_respond_to_host(vss_msg->error);
 }
 
 
 static void vss_send_op(struct work_struct *dummy)
 {
 	int op = vss_transaction.msg->vss_hdr.operation;
+	int rc;
 	struct cn_msg *msg;
 	struct hv_vss_msg *vss_msg;
 
@@ -98,7 +112,12 @@ static void vss_send_op(struct work_struct *dummy)
 	vss_msg->vss_hdr.operation = op;
 	msg->len = sizeof(struct hv_vss_msg);
 
-	cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
+	rc = cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
+	if (rc) {
+		pr_warn("VSS: failed to communicate to the daemon: %d\n", rc);
+		if (cancel_delayed_work_sync(&vss_timeout_work))
+			vss_respond_to_host(HV_E_FAIL);
+	}
 	kfree(msg);
 
 	return;
@@ -223,6 +242,8 @@ void hv_vss_onchannelcallback(void *context)
 			case VSS_OP_FREEZE:
 			case VSS_OP_THAW:
 				schedule_work(&vss_send_op_work);
+				schedule_delayed_work(&vss_timeout_work,
+						      VSS_USERSPACE_TIMEOUT);
 				return;
 
 			case VSS_OP_HOT_BACKUP:
@@ -277,5 +298,6 @@ hv_vss_init(struct hv_util_service *srv)
 void hv_vss_deinit(void)
 {
 	cn_del_callback(&vss_id);
+	cancel_delayed_work_sync(&vss_timeout_work);
 	cancel_work_sync(&vss_send_op_work);
 }