On 2019/11/20 9:08 下午, Alexander Shishkin wrote:

Commit a753bfcfdb1f ("intel_th: Make the switch allocate its subdevices") factored out intel_th_subdevice_alloc() from intel_th_populate(), but got the error path wrong, resulting in two instances of a double put_device() on a freshly initialized, but not 'added' device.

Fix this by only doing one put_device() in the error path.

Signed-off-by: Alexander Shishkin alexander.shishkin@linux.intel.com Fixes: a753bfcfdb1f ("intel_th: Make the switch allocate its subdevices") Reported-by: Wen Yang wenyang@linux.alibaba.com Reviewed-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Cc: stable@vger.kernel.org # v4.14+

---

drivers/hwtracing/intel_th/core.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/hwtracing/intel_th/core.c b/drivers/hwtracing/intel_th/core.c index d5c1821b31c6..0dfd97bbde9e 100644 --- a/drivers/hwtracing/intel_th/core.c +++ b/drivers/hwtracing/intel_th/core.c @@ -649,10 +649,8 @@ intel_th_subdevice_alloc(struct intel_th *th, } err = intel_th_device_add_resources(thdev, res, subdev->nres);

• if (err) {

• put_device(&thdev->dev);
  

• if (err) goto fail_put_device;

• }

if (subdev->type == INTEL_TH_OUTPUT) { if (subdev->mknode) @@ -667,10 +665,8 @@ intel_th_subdevice_alloc(struct intel_th *th, } err = device_add(&thdev->dev);

• if (err) {

• put_device(&thdev->dev);
  

• if (err) goto fail_free_res;

• }

/* need switch driver to be loaded to enumerate the rest */ if (subdev->type == INTEL_TH_SWITCH && !req) {

device_add() has increased the reference count,

so when it returns an error, an additional call to put_device()

is needed here to reduce the reference count.

--

Regards,

Wen