Merge tag 'drm-qemu-20161121' of git://git.kraxel.org/linux into drm-next

drm/virtio: fix busid in a different way, allocate more vbufs.
drm/qxl: various bugfixes and cleanups,

* tag 'drm-qemu-20161121' of git://git.kraxel.org/linux: (224 commits)
  drm/virtio: allocate some extra bufs
  qxl: Allow resolution which are not multiple of 8
  qxl: Don't notify userspace when monitors config is unchanged
  qxl: Remove qxl_bo_init() return value
  qxl: Call qxl_gem_{init, fini}
  qxl: Add missing '\n' to qxl_io_log() call
  qxl: Remove unused prototype
  qxl: Mark some internal functions as static
  Revert "drm: virtio: reinstate drm_virtio_set_busid()"
  drm/virtio: fix busid regression
  drm: re-export drm_dev_set_unique
  Linux 4.9-rc5
  gp8psk: Fix DVB frontend attach
  gp8psk: fix gp8psk_usb_in_op() logic
  dvb-usb: move data_mutex to struct dvb_usb_device
  iio: maxim_thermocouple: detect invalid storage size in read()
  aoe: fix crash in page count manipulation
  lightnvm: invalid offset calculation for lba_shift
  Kbuild: enable -Wmaybe-uninitialized warnings by default
  pcmcia: fix return value of soc_pcmcia_regulator_set
  ...

1 files changed, 11 insertions, 9 deletions

diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
index 59aa43cb146e..a41a79a4f4fe 100644
--- a/arch/arc/kernel/process.c
+++ b/arch/arc/kernel/process.c
@@ -43,8 +43,8 @@ SYSCALL_DEFINE0(arc_gettls)
 
 SYSCALL_DEFINE3(arc_usr_cmpxchg, int *, uaddr, int, expected, int, new)
 {
-	int uval;
-	int ret;
+	struct pt_regs *regs = current_pt_regs();
+	int uval = -EFAULT;
 
 	/*
 	 * This is only for old cores lacking LLOCK/SCOND, which by defintion
@@ -54,24 +54,26 @@ SYSCALL_DEFINE3(arc_usr_cmpxchg, int *, uaddr, int, expected, int, new)
 	 */
 	WARN_ON_ONCE(IS_ENABLED(CONFIG_SMP));
 
+	/* Z indicates to userspace if operation succeded */
+	regs->status32 &= ~STATUS_Z_MASK;
+
 	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
 		return -EFAULT;
 
 	preempt_disable();
 
-	ret = __get_user(uval, uaddr);
-	if (ret)
+	if (__get_user(uval, uaddr))
 		goto done;
 
-	if (uval != expected)
-		ret = -EAGAIN;
-	else
-		ret = __put_user(new, uaddr);
+	if (uval == expected) {
+		if (!__put_user(new, uaddr))
+			regs->status32 |= STATUS_Z_MASK;
+	}
 
 done:
 	preempt_enable();
 
-	return ret;
+	return uval;
 }
 
 void arch_cpu_idle(void)