Re: [PATCH v3 4/9] PM / QoS: Decouple request alloc from dev_pm_qos_mtx
From: Dan Carpenter
Date: Fri Aug 04 2023 - 05:29:29 EST
Hi Rob,
kernel test robot noticed the following build warnings:
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Rob-Clark/PM-devfreq-Drop-unneed-locking-to-appease-lockdep/20230804-060505
base: git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link: https://lore.kernel.org/r/20230803220202.78036-5-robdclark%40gmail.com
patch subject: [PATCH v3 4/9] PM / QoS: Decouple request alloc from dev_pm_qos_mtx
config: i386-randconfig-m021-20230730 (https://download.01.org/0day-ci/archive/20230804/202308041725.Npwswh0L-lkp@xxxxxxxxx/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce: (https://download.01.org/0day-ci/archive/20230804/202308041725.Npwswh0L-lkp@xxxxxxxxx/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
| Closes: https://lore.kernel.org/r/202308041725.Npwswh0L-lkp@xxxxxxxxx/
smatch warnings:
drivers/base/power/qos.c:973 dev_pm_qos_update_user_latency_tolerance() warn: possible memory leak of 'req'
vim +/req +973 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 {
b5ac35ff4296f7 Rob Clark 2023-08-03 925 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
211fb32e3a0547 Rob Clark 2023-08-03 928 ret = dev_pm_qos_constraints_ensure_allocated(dev);
211fb32e3a0547 Rob Clark 2023-08-03 929 if (ret)
211fb32e3a0547 Rob Clark 2023-08-03 930 return ret;
211fb32e3a0547 Rob Clark 2023-08-03 931
b5ac35ff4296f7 Rob Clark 2023-08-03 932 if (!dev->power.qos->latency_tolerance_req)
b5ac35ff4296f7 Rob Clark 2023-08-03 933 req = kzalloc(sizeof(*req), GFP_KERNEL);
b5ac35ff4296f7 Rob Clark 2023-08-03 934
2d984ad132a87c Rafael J. Wysocki 2014-02-11 935 mutex_lock(&dev_pm_qos_mtx);
2d984ad132a87c Rafael J. Wysocki 2014-02-11 936
211fb32e3a0547 Rob Clark 2023-08-03 937 if (!dev->power.qos->latency_tolerance_req) {
2d984ad132a87c Rafael J. Wysocki 2014-02-11 938 if (val < 0) {
80a6f7c79b7822 Andrew Lutomirski 2016-11-29 939 if (val == PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT)
80a6f7c79b7822 Andrew Lutomirski 2016-11-29 940 ret = 0;
80a6f7c79b7822 Andrew Lutomirski 2016-11-29 941 else
2d984ad132a87c Rafael J. Wysocki 2014-02-11 942 ret = -EINVAL;
2d984ad132a87c Rafael J. Wysocki 2014-02-11 943 goto out;
kfree(req);?
2d984ad132a87c Rafael J. Wysocki 2014-02-11 944 }
2d984ad132a87c Rafael J. Wysocki 2014-02-11 945 if (!req) {
2d984ad132a87c Rafael J. Wysocki 2014-02-11 946 ret = -ENOMEM;
2d984ad132a87c Rafael J. Wysocki 2014-02-11 947 goto out;
2d984ad132a87c Rafael J. Wysocki 2014-02-11 948 }
2d984ad132a87c Rafael J. Wysocki 2014-02-11 949 ret = __dev_pm_qos_add_request(dev, req, DEV_PM_QOS_LATENCY_TOLERANCE, val);
2d984ad132a87c Rafael J. Wysocki 2014-02-11 950 if (ret < 0) {
2d984ad132a87c Rafael J. Wysocki 2014-02-11 951 kfree(req);
2d984ad132a87c Rafael J. Wysocki 2014-02-11 952 goto out;
2d984ad132a87c Rafael J. Wysocki 2014-02-11 953 }
2d984ad132a87c Rafael J. Wysocki 2014-02-11 954 dev->power.qos->latency_tolerance_req = req;
2d984ad132a87c Rafael J. Wysocki 2014-02-11 955 } else {
b5ac35ff4296f7 Rob Clark 2023-08-03 956 /*
b5ac35ff4296f7 Rob Clark 2023-08-03 957 * If we raced with another thread to allocate the request,
b5ac35ff4296f7 Rob Clark 2023-08-03 958 * simply free the redundant allocation and move on.
b5ac35ff4296f7 Rob Clark 2023-08-03 959 */
b5ac35ff4296f7 Rob Clark 2023-08-03 960 if (req)
b5ac35ff4296f7 Rob Clark 2023-08-03 961 kfree(req);
b5ac35ff4296f7 Rob Clark 2023-08-03 962
2d984ad132a87c Rafael J. Wysocki 2014-02-11 963 if (val < 0) {
2d984ad132a87c Rafael J. Wysocki 2014-02-11 964 __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY_TOLERANCE);
2d984ad132a87c Rafael J. Wysocki 2014-02-11 965 ret = 0;
2d984ad132a87c Rafael J. Wysocki 2014-02-11 966 } else {
2d984ad132a87c Rafael J. Wysocki 2014-02-11 967 ret = __dev_pm_qos_update_request(dev->power.qos->latency_tolerance_req, val);
2d984ad132a87c Rafael J. Wysocki 2014-02-11 968 }
2d984ad132a87c Rafael J. Wysocki 2014-02-11 969 }
2d984ad132a87c Rafael J. Wysocki 2014-02-11 970
2d984ad132a87c Rafael J. Wysocki 2014-02-11 971 out:
2d984ad132a87c Rafael J. Wysocki 2014-02-11 972 mutex_unlock(&dev_pm_qos_mtx);
2d984ad132a87c Rafael J. Wysocki 2014-02-11 @973 return ret;
2d984ad132a87c Rafael J. Wysocki 2014-02-11 974 }
--
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