Merge tag 'v4.8' into patchwork

Linux 4.8

* tag 'v4.8': (1761 commits)
  Linux 4.8
  ARM: 8618/1: decompressor: reset ttbcr fields to use TTBR0 on ARMv7
  MIPS: CM: Fix mips_cm_max_vp_width for non-MT kernels on MT systems
  include/linux/property.h: fix typo/compile error
  ocfs2: fix deadlock on mmapped page in ocfs2_write_begin_nolock()
  mm: workingset: fix crash in shadow node shrinker caused by replace_page_cache_page()
  MAINTAINERS: Switch to kernel.org email address for Javi Merino
  x86/entry/64: Fix context tracking state warning when load_gs_index fails
  x86/boot: Initialize FPU and X86_FEATURE_ALWAYS even if we don't have CPUID
  x86/vdso: Fix building on big endian host
  x86/boot: Fix another __read_cr4() case on 486
  sctp: fix the issue sctp_diag uses lock_sock in rcu_read_lock
  sctp: change to check peer prsctp_capable when using prsctp polices
  sctp: remove prsctp_param from sctp_chunk
  sctp: move sent_count to the memory hole in sctp_chunk
  tg3: Avoid NULL pointer dereference in tg3_io_error_detected()
  x86/init: Fix cr4_init_shadow() on CR4-less machines
  MIPS: Fix detection of unsupported highmem with cache aliases
  MIPS: Malta: Fix IOCU disable switch read for MIPS64
  MIPS: Fix BUILD_ROLLBACK_PROLOGUE for microMIPS
  ...

1 files changed, 15 insertions, 8 deletions

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index d2406fe25533..5da47e26a012 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -165,6 +165,12 @@ struct ports_device {
 	 */
 	struct virtqueue *c_ivq, *c_ovq;
 
+	/*
+	 * A control packet buffer for guest->host requests, protected
+	 * by c_ovq_lock.
+	 */
+	struct virtio_console_control cpkt;
+
 	/* Array of per-port IO virtqueues */
 	struct virtqueue **in_vqs, **out_vqs;
 
@@ -560,28 +566,29 @@ static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
 				  unsigned int event, unsigned int value)
 {
 	struct scatterlist sg[1];
-	struct virtio_console_control cpkt;
 	struct virtqueue *vq;
 	unsigned int len;
 
 	if (!use_multiport(portdev))
 		return 0;
 
-	cpkt.id = cpu_to_virtio32(portdev->vdev, port_id);
-	cpkt.event = cpu_to_virtio16(portdev->vdev, event);
-	cpkt.value = cpu_to_virtio16(portdev->vdev, value);
-
 	vq = portdev->c_ovq;
 
-	sg_init_one(sg, &cpkt, sizeof(cpkt));
-
 	spin_lock(&portdev->c_ovq_lock);
-	if (virtqueue_add_outbuf(vq, sg, 1, &cpkt, GFP_ATOMIC) == 0) {
+
+	portdev->cpkt.id = cpu_to_virtio32(portdev->vdev, port_id);
+	portdev->cpkt.event = cpu_to_virtio16(portdev->vdev, event);
+	portdev->cpkt.value = cpu_to_virtio16(portdev->vdev, value);
+
+	sg_init_one(sg, &portdev->cpkt, sizeof(struct virtio_console_control));
+
+	if (virtqueue_add_outbuf(vq, sg, 1, &portdev->cpkt, GFP_ATOMIC) == 0) {
 		virtqueue_kick(vq);
 		while (!virtqueue_get_buf(vq, &len)
 			&& !virtqueue_is_broken(vq))
 			cpu_relax();
 	}
+
 	spin_unlock(&portdev->c_ovq_lock);
 	return 0;
 }