Merge tag 'char-misc-5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc into master

Pull char/misc fixes from Greg KH:
 "Here are number of small char/misc driver fixes for 5.8-rc6

  Not that many complex fixes here, just a number of small fixes for
  reported issues, and some new device ids. Nothing fancy.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (21 commits)
  virtio: virtio_console: add missing MODULE_DEVICE_TABLE() for rproc serial
  intel_th: Fix a NULL dereference when hub driver is not loaded
  intel_th: pci: Add Emmitsburg PCH support
  intel_th: pci: Add Tiger Lake PCH-H support
  intel_th: pci: Add Jasper Lake CPU support
  virt: vbox: Fix guest capabilities mask check
  virt: vbox: Fix VBGL_IOCTL_VMMDEV_REQUEST_BIG and _LOG req numbers to match upstream
  uio_pdrv_genirq: fix use without device tree and no interrupt
  uio_pdrv_genirq: Remove warning when irq is not specified
  coresight: etmv4: Fix CPU power management setup in probe() function
  coresight: cti: Fix error handling in probe
  Revert "zram: convert remaining CLASS_ATTR() to CLASS_ATTR_RO()"
  mei: bus: don't clean driver pointer
  misc: atmel-ssc: lock with mutex instead of spinlock
  phy: sun4i-usb: fix dereference of pointer phy0 before it is null checked
  phy: rockchip: Fix return value of inno_dsidphy_probe()
  phy: ti: j721e-wiz: Constify structs
  phy: ti: am654-serdes: Constify regmap_config
  phy: intel: fix enum type mismatch warning
  phy: intel: Fix compilation error on FIELD_PREP usage
  ...

1 files changed, 18 insertions, 3 deletions

diff --git a/drivers/hwtracing/intel_th/core.c b/drivers/hwtracing/intel_th/core.c
index ca232ec565e8..c9ac3dc65113 100644
--- a/drivers/hwtracing/intel_th/core.c
+++ b/drivers/hwtracing/intel_th/core.c
@@ -1021,15 +1021,30 @@ int intel_th_set_output(struct intel_th_device *thdev,
 {
 	struct intel_th_device *hub = to_intel_th_hub(thdev);
 	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
+	int ret;
 
 	/* In host mode, this is up to the external debugger, do nothing. */
 	if (hub->host_mode)
 		return 0;
 
-	if (!hubdrv->set_output)
-		return -ENOTSUPP;
+	/*
+	 * hub is instantiated together with the source device that
+	 * calls here, so guaranteed to be present.
+	 */
+	hubdrv = to_intel_th_driver(hub->dev.driver);
+	if (!hubdrv || !try_module_get(hubdrv->driver.owner))
+		return -EINVAL;
+
+	if (!hubdrv->set_output) {
+		ret = -ENOTSUPP;
+		goto out;
+	}
+
+	ret = hubdrv->set_output(hub, master);
 
-	return hubdrv->set_output(hub, master);
+out:
+	module_put(hubdrv->driver.owner);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(intel_th_set_output);