Hi Rob,

https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    
https://github.com/intel-lab-lkp/linux/commits/Rob-Clark/drm-msm-Pre-allocate-hw_fence/20230320-224826
base:   git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link:    
https://lore.kernel.org/r/20230320144356.803762-19-robdclark%40gmail.com
patch subject: [PATCH v2 18/23] PM / QoS: Decouple request alloc from 
dev_pm_qos_mtx
config: arm64-randconfig-m041-20230319 
(https://download.01.org/0day-ci/archive/20230321/[email protected]/config)
compiler: aarch64-linux-gcc (GCC) 12.1.0

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
| Reported-by: Dan Carpenter <[email protected]>
| Link: https://lore.kernel.org/r/[email protected]/

smatch warnings:
drivers/base/power/qos.c:947 dev_pm_qos_update_user_latency_tolerance() error: 
uninitialized symbol 'req'.
drivers/base/power/qos.c:975 dev_pm_qos_update_user_latency_tolerance() warn: 
possible memory leak of 'req'

vim +/req +947 drivers/base/power/qos.c

2d984ad132a87c Rafael J. Wysocki 2014-02-11  923  int 
dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val)
2d984ad132a87c Rafael J. Wysocki 2014-02-11  924  {
2d7e4629d7265d Rob Clark         2023-03-20  925        struct 
dev_pm_qos_request *req = NULL;
2d984ad132a87c Rafael J. Wysocki 2014-02-11  926        int ret;
2d984ad132a87c Rafael J. Wysocki 2014-02-11  927  
00dd582e52a535 Rob Clark         2023-03-20  928        ret = 
dev_pm_qos_constraints_ensure_allocated(dev);
00dd582e52a535 Rob Clark         2023-03-20  929        if (ret)
00dd582e52a535 Rob Clark         2023-03-20  930                return ret;
00dd582e52a535 Rob Clark         2023-03-20  931  
2d7e4629d7265d Rob Clark         2023-03-20  932        if 
(!dev->power.qos->latency_tolerance_req)
2d7e4629d7265d Rob Clark         2023-03-20  933                req = 
kzalloc(sizeof(*req), GFP_KERNEL);
2d7e4629d7265d Rob Clark         2023-03-20  934  
2d984ad132a87c Rafael J. Wysocki 2014-02-11  935        
mutex_lock(&dev_pm_qos_mtx);
2d984ad132a87c Rafael J. Wysocki 2014-02-11  936  
00dd582e52a535 Rob Clark         2023-03-20  937        if 
(!dev->power.qos->latency_tolerance_req) {
2d984ad132a87c Rafael J. Wysocki 2014-02-11  938                struct 
dev_pm_qos_request *req;

This "req" shadows the ealier req.

2d984ad132a87c Rafael J. Wysocki 2014-02-11  939  
2d984ad132a87c Rafael J. Wysocki 2014-02-11  940                if (val < 0) {
80a6f7c79b7822 Andrew Lutomirski 2016-11-29  941                        if (val 
== PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT)
80a6f7c79b7822 Andrew Lutomirski 2016-11-29  942                                
ret = 0;
80a6f7c79b7822 Andrew Lutomirski 2016-11-29  943                        else
2d984ad132a87c Rafael J. Wysocki 2014-02-11  944                                
ret = -EINVAL;
2d984ad132a87c Rafael J. Wysocki 2014-02-11  945                        goto 
out;
2d984ad132a87c Rafael J. Wysocki 2014-02-11  946                }
2d984ad132a87c Rafael J. Wysocki 2014-02-11 @947                if (!req) {

So it leads to an unintialized variable and a leak.

2d984ad132a87c Rafael J. Wysocki 2014-02-11  948                        ret = 
-ENOMEM;
2d984ad132a87c Rafael J. Wysocki 2014-02-11  949                        goto 
out;
2d984ad132a87c Rafael J. Wysocki 2014-02-11  950                }
2d984ad132a87c Rafael J. Wysocki 2014-02-11  951                ret = 
__dev_pm_qos_add_request(dev, req, DEV_PM_QOS_LATENCY_TOLERANCE, val);
2d984ad132a87c Rafael J. Wysocki 2014-02-11  952                if (ret < 0) {
2d984ad132a87c Rafael J. Wysocki 2014-02-11  953                        
kfree(req);
2d984ad132a87c Rafael J. Wysocki 2014-02-11  954                        goto 
out;
2d984ad132a87c Rafael J. Wysocki 2014-02-11  955                }
2d984ad132a87c Rafael J. Wysocki 2014-02-11  956                
dev->power.qos->latency_tolerance_req = req;
2d984ad132a87c Rafael J. Wysocki 2014-02-11  957        } else {
2d7e4629d7265d Rob Clark         2023-03-20  958                /*
2d7e4629d7265d Rob Clark         2023-03-20  959                 * If we raced 
with another thread to allocate the request,
2d7e4629d7265d Rob Clark         2023-03-20  960                 * simply free 
the redundant allocation and move on.
2d7e4629d7265d Rob Clark         2023-03-20  961                 */
2d7e4629d7265d Rob Clark         2023-03-20  962                if (req)
2d7e4629d7265d Rob Clark         2023-03-20  963                        
kfree(req);
2d7e4629d7265d Rob Clark         2023-03-20  964  
2d984ad132a87c Rafael J. Wysocki 2014-02-11  965                if (val < 0) {
2d984ad132a87c Rafael J. Wysocki 2014-02-11  966                        
__dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY_TOLERANCE);
2d984ad132a87c Rafael J. Wysocki 2014-02-11  967                        ret = 0;
2d984ad132a87c Rafael J. Wysocki 2014-02-11  968                } else {
2d984ad132a87c Rafael J. Wysocki 2014-02-11  969                        ret = 
__dev_pm_qos_update_request(dev->power.qos->latency_tolerance_req, val);
2d984ad132a87c Rafael J. Wysocki 2014-02-11  970                }
2d984ad132a87c Rafael J. Wysocki 2014-02-11  971        }
2d984ad132a87c Rafael J. Wysocki 2014-02-11  972  
2d984ad132a87c Rafael J. Wysocki 2014-02-11  973   out:
2d984ad132a87c Rafael J. Wysocki 2014-02-11  974        
mutex_unlock(&dev_pm_qos_mtx);
2d984ad132a87c Rafael J. Wysocki 2014-02-11 @975        return ret;
2d984ad132a87c Rafael J. Wysocki 2014-02-11  976  }

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests

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