Hi Greg, Thanks for having a look. Comment below. On 02/03/2017 11:56 AM, Greg KH wrote: > On Wed, Feb 01, 2017 at 05:43:22AM -0600, laurentiu.tudor@xxxxxxx wrote: >> From: Laurentiu Tudor <laurentiu.tudor@xxxxxxx> >> >> Drop unneeded get_device() call at device creation >> and, as per documentation, drop reference count >> after using device_find_child() return. >> >> Signed-off-by: Laurentiu Tudor <laurentiu.tudor@xxxxxxx> >> --- >> drivers/staging/fsl-mc/bus/dprc-driver.c | 1 + >> drivers/staging/fsl-mc/bus/fsl-mc-bus.c | 1 - >> 2 files changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/staging/fsl-mc/bus/dprc-driver.c b/drivers/staging/fsl-mc/bus/dprc-driver.c >> index 4e416d8..e4b0341 100644 >> --- a/drivers/staging/fsl-mc/bus/dprc-driver.c >> +++ b/drivers/staging/fsl-mc/bus/dprc-driver.c >> @@ -188,6 +188,7 @@ static void dprc_add_new_devices(struct fsl_mc_device *mc_bus_dev, >> child_dev = fsl_mc_device_lookup(obj_desc, mc_bus_dev); >> if (child_dev) { >> check_plugged_state_change(child_dev, obj_desc); >> + put_device(&child_dev->dev); >> continue; >> } >> >> diff --git a/drivers/staging/fsl-mc/bus/fsl-mc-bus.c b/drivers/staging/fsl-mc/bus/fsl-mc-bus.c >> index cc20dc4..7c6a43b 100644 >> --- a/drivers/staging/fsl-mc/bus/fsl-mc-bus.c >> +++ b/drivers/staging/fsl-mc/bus/fsl-mc-bus.c >> @@ -537,7 +537,6 @@ int fsl_mc_device_add(struct dprc_obj_desc *obj_desc, >> goto error_cleanup_dev; >> } >> >> - (void)get_device(&mc_dev->dev); > > This implies that your device reference counting is totally wrong and > messed up. Does this fix anything? Break anything? It should do > something different now... It fixes the refcounting in the sense that I'm now seeing the error that i think you were referring to in your previous reviews, when we hot unplug a device: "Device 'foo.N' does not have a release() function, it is broken and must be fixed." See next patch that adds the required callback. Regarding this particular get_device(), i have no clue why the original author placed it here. I've looked over other bus implementations and didn't see something similar. --- Best Regards, Laurentiu _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel