4.14-stable review patch. If anyone has any objections, please let me know.
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From: Alexander Shishkin alexander.shishkin@linux.intel.com
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 alexander.shishkin@linux.intel.com Fixes: a753bfcfdb1f ("intel_th: Make the switch allocate its subdevices") CC: stable@vger.kernel.org # v4.14+ Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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)