From: Alexander Shishkin Date: Fri, 8 Apr 2016 14:35:04 +0000 (+0300) Subject: intel_th: Hold output driver module reference while capture is active X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=e2ea295baf87d78f2ed86ce595b30c691b18b210;p=openwrt%2Fstaging%2Fblogic.git intel_th: Hold output driver module reference while capture is active Right now it's possible to unload the output subdevice's driver while the capture to this output is active. Prevent this by holding the output driver's module reference. Signed-off-by: Alexander Shishkin Reviewed-by: Laurent Fert --- diff --git a/drivers/hwtracing/intel_th/core.c b/drivers/hwtracing/intel_th/core.c index 20339470c2c6..1be543e8e42f 100644 --- a/drivers/hwtracing/intel_th/core.c +++ b/drivers/hwtracing/intel_th/core.c @@ -189,6 +189,9 @@ static int intel_th_output_activate(struct intel_th_device *thdev) if (!thdrv) return -ENODEV; + if (!try_module_get(thdrv->driver.owner)) + return -ENODEV; + if (thdrv->activate) return thdrv->activate(thdev); @@ -209,6 +212,8 @@ static void intel_th_output_deactivate(struct intel_th_device *thdev) thdrv->deactivate(thdev); else intel_th_trace_disable(thdev); + + module_put(thdrv->driver.owner); } static ssize_t active_show(struct device *dev, struct device_attribute *attr,