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+ --- drivers/hwtracing/intel_th/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/hwtracing/intel_th/core.c b/drivers/hwtracing/intel_th/core.c index da962aa2cef5..4e70ecee2103 100644 --- a/drivers/hwtracing/intel_th/core.c +++ b/drivers/hwtracing/intel_th/core.c @@ -139,7 +139,8 @@ static int intel_th_remove(struct device *dev) th->thdev[i] = NULL; } - th->num_thdevs = lowest; + if (lowest >= 0) + th->num_thdevs = lowest; } if (thdrv->attr_group) -- 2.18.0
