>> So in summary this problem is showing up now as the 'User Helper >> Fallback' >> is now forced on, obviously the underlying problem needs to be fixed - >> but >> I don't know when it crept in. >> > > The 'CONFIG_FW_LOADER_USER_HELPER_FALLBACK' enables to load firmware > data manually by accessing /sys/class/firmware/<name>/data. It runs in > case the firmware file is missing. > This user helper fallback will be enabled if one of LP55xx driver is > included in your dot config. Please see my patch below. > > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/drivers/leds?id=b67893206fc0a0e8af87130e67f3d8ae553fc87c > > However, I'm not sure why this affects your system lockup. Can I have > more details? Hi Milo, I'm not suggesting that your patch is the cause, just that it is an 'enabler' and and explains why the problem (system lockup when I plug USB Bluetooth dongle in) appears now. A full Oops log is further back in this thread: http://www.spinics.net/lists/linux-bluetooth/msg63090.html >> Will try building 4.1 with this option to see if it fails. A very quick test as I was leaving the house this morning shows that 4.1 with 'CONFIG_FW_LOADER_USER_HELPER_FALLBACK' does not show the problem. So at least we know the 'real' problem is a recent change to the code. Simon -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html