4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Alexander Shishkin <[email protected]> commit 8801922cd94c918e4dc3a108ecaa500c4d40583f upstream. Commit a753bfcfdb1f ("intel_th: Make the switch allocate its subdevices") brings in new subdevice addition/removal logic that's broken for "host mode": the SWITCH device has no children to begin with, which is not handled in the code. This results in a null dereference bug later down the path. This patch fixes the subdevice removal code to handle host mode correctly. Signed-off-by: Alexander Shishkin <[email protected]> Fixes: a753bfcfdb1f ("intel_th: Make the switch allocate its subdevices") CC: [email protected] # v4.14+ Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/hwtracing/intel_th/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/hwtracing/intel_th/core.c +++ b/drivers/hwtracing/intel_th/core.c @@ -147,7 +147,8 @@ static int intel_th_remove(struct device th->thdev[i] = NULL; } - th->num_thdevs = lowest; + if (lowest >= 0) + th->num_thdevs = lowest; } if (thdrv->attr_group)
