* kernel/power/energy_model.c:649 em_dev_register_pd_no_update() error: we previously assumed 'dev->em_pd' could be null (see line 594)
@ 2026-07-30 8:15 kernel test robot
0 siblings, 0 replies; 3+ messages in thread
From: kernel test robot @ 2026-07-30 8:15 UTC (permalink / raw)
To: oe-kbuild; +Cc: lkp, Dan Carpenter
BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
CC: linux-kernel@vger.kernel.org
TO: "Rafael J. Wysocki" <rjw@rjwysocki.net>
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 11028ab62899e4191e074ee364c712b77823a9c4
commit: e0423541477dfb684fbc6e6b5386054bc650f264 PM: EM: Add function for registering a PD without capacity update
date: 11 months ago
:::::: branch date: 8 hours ago
:::::: commit date: 11 months ago
config: i386-randconfig-141-20260730 (https://download.01.org/0day-ci/archive/20260730/202607301623.Di8IVRXB-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
smatch: v0.5.0-9187-g5189e3fb
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
| Fixes: e0423541477d ("PM: EM: Add function for registering a PD without capacity update")
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Closes: https://lore.kernel.org/r/202607301623.Di8IVRXB-lkp@intel.com/
smatch warnings:
kernel/power/energy_model.c:649 em_dev_register_pd_no_update() error: we previously assumed 'dev->em_pd' could be null (see line 594)
vim +649 kernel/power/energy_model.c
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 564
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 565 /**
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 566 * em_dev_register_pd_no_update() - Register a perf domain for a device
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 567 * @dev : Device to register the PD for
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 568 * @nr_states : Number of performance states in the new PD
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 569 * @cb : Callback functions for populating the energy model
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 570 * @cpus : CPUs to include in the new PD (mandatory if @dev is a CPU device)
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 571 * @microwatts : Whether or not the power values in the EM will be in uW
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 572 *
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 573 * Like em_dev_register_perf_domain(), but does not trigger a CPU capacity
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 574 * update after registering the PD, even if @dev is a CPU device.
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 575 */
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 576 int em_dev_register_pd_no_update(struct device *dev, unsigned int nr_states,
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 577 const struct em_data_callback *cb,
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 578 const cpumask_t *cpus, bool microwatts)
27871f7a8a341ef Quentin Perret 2018-12-03 579 {
3ee7be9e10dd5f7 Rafael J. Wysocki 2025-03-06 580 struct em_perf_table *em_table;
27871f7a8a341ef Quentin Perret 2018-12-03 581 unsigned long cap, prev_cap = 0;
91362463114eb63 Lukasz Luba 2022-03-21 582 unsigned long flags = 0;
1bc138c62295997 Lukasz Luba 2020-06-10 583 int cpu, ret;
27871f7a8a341ef Quentin Perret 2018-12-03 584
1bc138c62295997 Lukasz Luba 2020-06-10 585 if (!dev || !nr_states || !cb)
27871f7a8a341ef Quentin Perret 2018-12-03 586 return -EINVAL;
27871f7a8a341ef Quentin Perret 2018-12-03 587
27871f7a8a341ef Quentin Perret 2018-12-03 588 /*
27871f7a8a341ef Quentin Perret 2018-12-03 589 * Use a mutex to serialize the registration of performance domains and
27871f7a8a341ef Quentin Perret 2018-12-03 590 * let the driver-defined callback functions sleep.
27871f7a8a341ef Quentin Perret 2018-12-03 591 */
27871f7a8a341ef Quentin Perret 2018-12-03 592 mutex_lock(&em_pd_mutex);
27871f7a8a341ef Quentin Perret 2018-12-03 593
1bc138c62295997 Lukasz Luba 2020-06-10 @594 if (dev->em_pd) {
27871f7a8a341ef Quentin Perret 2018-12-03 595 ret = -EEXIST;
27871f7a8a341ef Quentin Perret 2018-12-03 596 goto unlock;
27871f7a8a341ef Quentin Perret 2018-12-03 597 }
27871f7a8a341ef Quentin Perret 2018-12-03 598
1bc138c62295997 Lukasz Luba 2020-06-10 599 if (_is_cpu_device(dev)) {
1bc138c62295997 Lukasz Luba 2020-06-10 600 if (!cpus) {
1bc138c62295997 Lukasz Luba 2020-06-10 601 dev_err(dev, "EM: invalid CPU mask\n");
1bc138c62295997 Lukasz Luba 2020-06-10 602 ret = -EINVAL;
1bc138c62295997 Lukasz Luba 2020-06-10 603 goto unlock;
1bc138c62295997 Lukasz Luba 2020-06-10 604 }
1bc138c62295997 Lukasz Luba 2020-06-10 605
1bc138c62295997 Lukasz Luba 2020-06-10 606 for_each_cpu(cpu, cpus) {
1bc138c62295997 Lukasz Luba 2020-06-10 607 if (em_cpu_get(cpu)) {
1bc138c62295997 Lukasz Luba 2020-06-10 608 dev_err(dev, "EM: exists for CPU%d\n", cpu);
1bc138c62295997 Lukasz Luba 2020-06-10 609 ret = -EEXIST;
1bc138c62295997 Lukasz Luba 2020-06-10 610 goto unlock;
1bc138c62295997 Lukasz Luba 2020-06-10 611 }
27871f7a8a341ef Quentin Perret 2018-12-03 612 /*
1bc138c62295997 Lukasz Luba 2020-06-10 613 * All CPUs of a domain must have the same
1bc138c62295997 Lukasz Luba 2020-06-10 614 * micro-architecture since they all share the same
1bc138c62295997 Lukasz Luba 2020-06-10 615 * table.
27871f7a8a341ef Quentin Perret 2018-12-03 616 */
8ec59c0f5f4966f Vincent Guittot 2019-06-17 617 cap = arch_scale_cpu_capacity(cpu);
27871f7a8a341ef Quentin Perret 2018-12-03 618 if (prev_cap && prev_cap != cap) {
1bc138c62295997 Lukasz Luba 2020-06-10 619 dev_err(dev, "EM: CPUs of %*pbl must have the same capacity\n",
1bc138c62295997 Lukasz Luba 2020-06-10 620 cpumask_pr_args(cpus));
1bc138c62295997 Lukasz Luba 2020-06-10 621
27871f7a8a341ef Quentin Perret 2018-12-03 622 ret = -EINVAL;
27871f7a8a341ef Quentin Perret 2018-12-03 623 goto unlock;
27871f7a8a341ef Quentin Perret 2018-12-03 624 }
27871f7a8a341ef Quentin Perret 2018-12-03 625 prev_cap = cap;
27871f7a8a341ef Quentin Perret 2018-12-03 626 }
1bc138c62295997 Lukasz Luba 2020-06-10 627 }
27871f7a8a341ef Quentin Perret 2018-12-03 628
ae6ccaa650380d2 Lukasz Luba 2022-07-07 629 if (microwatts)
ae6ccaa650380d2 Lukasz Luba 2022-07-07 630 flags |= EM_PERF_DOMAIN_MICROWATTS;
91362463114eb63 Lukasz Luba 2022-03-21 631 else if (cb->get_cost)
91362463114eb63 Lukasz Luba 2022-03-21 632 flags |= EM_PERF_DOMAIN_ARTIFICIAL;
91362463114eb63 Lukasz Luba 2022-03-21 633
3acec69a94eaaf3 Lukasz Luba 2024-03-08 634 /*
3acec69a94eaaf3 Lukasz Luba 2024-03-08 635 * EM only supports uW (exception is artificial EM).
3acec69a94eaaf3 Lukasz Luba 2024-03-08 636 * Therefore, check and force the drivers to provide
3acec69a94eaaf3 Lukasz Luba 2024-03-08 637 * power in uW.
3acec69a94eaaf3 Lukasz Luba 2024-03-08 638 */
3acec69a94eaaf3 Lukasz Luba 2024-03-08 639 if (!microwatts && !(flags & EM_PERF_DOMAIN_ARTIFICIAL)) {
3acec69a94eaaf3 Lukasz Luba 2024-03-08 640 dev_err(dev, "EM: only supports uW power values\n");
3acec69a94eaaf3 Lukasz Luba 2024-03-08 641 ret = -EINVAL;
3acec69a94eaaf3 Lukasz Luba 2024-03-08 642 goto unlock;
3acec69a94eaaf3 Lukasz Luba 2024-03-08 643 }
3acec69a94eaaf3 Lukasz Luba 2024-03-08 644
91362463114eb63 Lukasz Luba 2022-03-21 645 ret = em_create_pd(dev, nr_states, cb, cpus, flags);
1bc138c62295997 Lukasz Luba 2020-06-10 646 if (ret)
27871f7a8a341ef Quentin Perret 2018-12-03 647 goto unlock;
27871f7a8a341ef Quentin Perret 2018-12-03 648
91362463114eb63 Lukasz Luba 2022-03-21 @649 dev->em_pd->flags |= flags;
5609296750afd64 Lukasz Luba 2024-10-30 650 dev->em_pd->min_perf_state = 0;
5609296750afd64 Lukasz Luba 2024-10-30 651 dev->em_pd->max_perf_state = nr_states - 1;
c250d50fe2ce627 Lukasz Luba 2020-11-05 652
3ee7be9e10dd5f7 Rafael J. Wysocki 2025-03-06 653 em_table = rcu_dereference_protected(dev->em_pd->em_table,
3ee7be9e10dd5f7 Rafael J. Wysocki 2025-03-06 654 lockdep_is_held(&em_pd_mutex));
3ee7be9e10dd5f7 Rafael J. Wysocki 2025-03-06 655 em_cpufreq_update_efficiencies(dev, em_table->state);
e458716a92b57f8 Vincent Donnefort 2021-09-08 656
1bc138c62295997 Lukasz Luba 2020-06-10 657 em_debug_create_pd(dev);
1bc138c62295997 Lukasz Luba 2020-06-10 658 dev_info(dev, "EM: created perf domain\n");
27871f7a8a341ef Quentin Perret 2018-12-03 659
27871f7a8a341ef Quentin Perret 2018-12-03 660 unlock:
27871f7a8a341ef Quentin Perret 2018-12-03 661 mutex_unlock(&em_pd_mutex);
e3f1164fc9ee843 Lukasz Luba 2024-02-08 662
27871f7a8a341ef Quentin Perret 2018-12-03 663 return ret;
27871f7a8a341ef Quentin Perret 2018-12-03 664 }
e0423541477dfb6 Rafael J. Wysocki 2025-09-05 665 EXPORT_SYMBOL_GPL(em_dev_register_pd_no_update);
7d9895c7fbfc9c7 Lukasz Luba 2020-05-27 666
:::::: The code at line 649 was first introduced by commit
:::::: 91362463114eb63ead5f02c11d58c46064c339e7 PM: EM: Use the new .get_cost() callback while registering EM
:::::: TO: Lukasz Luba <lukasz.luba@arm.com>
:::::: CC: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 3+ messages in thread* kernel/power/energy_model.c:649 em_dev_register_pd_no_update() error: we previously assumed 'dev->em_pd' could be null (see line 594)
@ 2026-04-17 11:59 kernel test robot
0 siblings, 0 replies; 3+ messages in thread
From: kernel test robot @ 2026-04-17 11:59 UTC (permalink / raw)
To: oe-kbuild; +Cc: lkp, Dan Carpenter
BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
CC: linux-kernel@vger.kernel.org
TO: "Rafael J. Wysocki" <rjw@rjwysocki.net>
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 43cfbdda5af60ffc6272a7b8c5c37d1d0a181ca9
commit: e0423541477dfb684fbc6e6b5386054bc650f264 PM: EM: Add function for registering a PD without capacity update
date: 7 months ago
:::::: branch date: 8 hours ago
:::::: commit date: 7 months ago
config: powerpc64-randconfig-r073-20260417 (https://download.01.org/0day-ci/archive/20260417/202604171910.UyL0lHLt-lkp@intel.com/config)
compiler: clang version 23.0.0git (https://github.com/llvm/llvm-project 5bac06718f502014fade905512f1d26d578a18f3)
smatch: v0.5.0-9007-gcf3ea02b
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
| Fixes: e0423541477d ("PM: EM: Add function for registering a PD without capacity update")
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Closes: https://lore.kernel.org/r/202604171910.UyL0lHLt-lkp@intel.com/
smatch warnings:
kernel/power/energy_model.c:649 em_dev_register_pd_no_update() error: we previously assumed 'dev->em_pd' could be null (see line 594)
vim +649 kernel/power/energy_model.c
e0423541477dfb Rafael J. Wysocki 2025-09-05 564
e0423541477dfb Rafael J. Wysocki 2025-09-05 565 /**
e0423541477dfb Rafael J. Wysocki 2025-09-05 566 * em_dev_register_pd_no_update() - Register a perf domain for a device
e0423541477dfb Rafael J. Wysocki 2025-09-05 567 * @dev : Device to register the PD for
e0423541477dfb Rafael J. Wysocki 2025-09-05 568 * @nr_states : Number of performance states in the new PD
e0423541477dfb Rafael J. Wysocki 2025-09-05 569 * @cb : Callback functions for populating the energy model
e0423541477dfb Rafael J. Wysocki 2025-09-05 570 * @cpus : CPUs to include in the new PD (mandatory if @dev is a CPU device)
e0423541477dfb Rafael J. Wysocki 2025-09-05 571 * @microwatts : Whether or not the power values in the EM will be in uW
e0423541477dfb Rafael J. Wysocki 2025-09-05 572 *
e0423541477dfb Rafael J. Wysocki 2025-09-05 573 * Like em_dev_register_perf_domain(), but does not trigger a CPU capacity
e0423541477dfb Rafael J. Wysocki 2025-09-05 574 * update after registering the PD, even if @dev is a CPU device.
e0423541477dfb Rafael J. Wysocki 2025-09-05 575 */
e0423541477dfb Rafael J. Wysocki 2025-09-05 576 int em_dev_register_pd_no_update(struct device *dev, unsigned int nr_states,
e0423541477dfb Rafael J. Wysocki 2025-09-05 577 const struct em_data_callback *cb,
e0423541477dfb Rafael J. Wysocki 2025-09-05 578 const cpumask_t *cpus, bool microwatts)
27871f7a8a341e Quentin Perret 2018-12-03 579 {
3ee7be9e10dd5f Rafael J. Wysocki 2025-03-06 580 struct em_perf_table *em_table;
27871f7a8a341e Quentin Perret 2018-12-03 581 unsigned long cap, prev_cap = 0;
91362463114eb6 Lukasz Luba 2022-03-21 582 unsigned long flags = 0;
1bc138c6229599 Lukasz Luba 2020-06-10 583 int cpu, ret;
27871f7a8a341e Quentin Perret 2018-12-03 584
1bc138c6229599 Lukasz Luba 2020-06-10 585 if (!dev || !nr_states || !cb)
27871f7a8a341e Quentin Perret 2018-12-03 586 return -EINVAL;
27871f7a8a341e Quentin Perret 2018-12-03 587
27871f7a8a341e Quentin Perret 2018-12-03 588 /*
27871f7a8a341e Quentin Perret 2018-12-03 589 * Use a mutex to serialize the registration of performance domains and
27871f7a8a341e Quentin Perret 2018-12-03 590 * let the driver-defined callback functions sleep.
27871f7a8a341e Quentin Perret 2018-12-03 591 */
27871f7a8a341e Quentin Perret 2018-12-03 592 mutex_lock(&em_pd_mutex);
27871f7a8a341e Quentin Perret 2018-12-03 593
1bc138c6229599 Lukasz Luba 2020-06-10 @594 if (dev->em_pd) {
27871f7a8a341e Quentin Perret 2018-12-03 595 ret = -EEXIST;
27871f7a8a341e Quentin Perret 2018-12-03 596 goto unlock;
27871f7a8a341e Quentin Perret 2018-12-03 597 }
27871f7a8a341e Quentin Perret 2018-12-03 598
1bc138c6229599 Lukasz Luba 2020-06-10 599 if (_is_cpu_device(dev)) {
1bc138c6229599 Lukasz Luba 2020-06-10 600 if (!cpus) {
1bc138c6229599 Lukasz Luba 2020-06-10 601 dev_err(dev, "EM: invalid CPU mask\n");
1bc138c6229599 Lukasz Luba 2020-06-10 602 ret = -EINVAL;
1bc138c6229599 Lukasz Luba 2020-06-10 603 goto unlock;
1bc138c6229599 Lukasz Luba 2020-06-10 604 }
1bc138c6229599 Lukasz Luba 2020-06-10 605
1bc138c6229599 Lukasz Luba 2020-06-10 606 for_each_cpu(cpu, cpus) {
1bc138c6229599 Lukasz Luba 2020-06-10 607 if (em_cpu_get(cpu)) {
1bc138c6229599 Lukasz Luba 2020-06-10 608 dev_err(dev, "EM: exists for CPU%d\n", cpu);
1bc138c6229599 Lukasz Luba 2020-06-10 609 ret = -EEXIST;
1bc138c6229599 Lukasz Luba 2020-06-10 610 goto unlock;
1bc138c6229599 Lukasz Luba 2020-06-10 611 }
27871f7a8a341e Quentin Perret 2018-12-03 612 /*
1bc138c6229599 Lukasz Luba 2020-06-10 613 * All CPUs of a domain must have the same
1bc138c6229599 Lukasz Luba 2020-06-10 614 * micro-architecture since they all share the same
1bc138c6229599 Lukasz Luba 2020-06-10 615 * table.
27871f7a8a341e Quentin Perret 2018-12-03 616 */
8ec59c0f5f4966 Vincent Guittot 2019-06-17 617 cap = arch_scale_cpu_capacity(cpu);
27871f7a8a341e Quentin Perret 2018-12-03 618 if (prev_cap && prev_cap != cap) {
1bc138c6229599 Lukasz Luba 2020-06-10 619 dev_err(dev, "EM: CPUs of %*pbl must have the same capacity\n",
1bc138c6229599 Lukasz Luba 2020-06-10 620 cpumask_pr_args(cpus));
1bc138c6229599 Lukasz Luba 2020-06-10 621
27871f7a8a341e Quentin Perret 2018-12-03 622 ret = -EINVAL;
27871f7a8a341e Quentin Perret 2018-12-03 623 goto unlock;
27871f7a8a341e Quentin Perret 2018-12-03 624 }
27871f7a8a341e Quentin Perret 2018-12-03 625 prev_cap = cap;
27871f7a8a341e Quentin Perret 2018-12-03 626 }
1bc138c6229599 Lukasz Luba 2020-06-10 627 }
27871f7a8a341e Quentin Perret 2018-12-03 628
ae6ccaa650380d Lukasz Luba 2022-07-07 629 if (microwatts)
ae6ccaa650380d Lukasz Luba 2022-07-07 630 flags |= EM_PERF_DOMAIN_MICROWATTS;
91362463114eb6 Lukasz Luba 2022-03-21 631 else if (cb->get_cost)
91362463114eb6 Lukasz Luba 2022-03-21 632 flags |= EM_PERF_DOMAIN_ARTIFICIAL;
91362463114eb6 Lukasz Luba 2022-03-21 633
3acec69a94eaaf Lukasz Luba 2024-03-08 634 /*
3acec69a94eaaf Lukasz Luba 2024-03-08 635 * EM only supports uW (exception is artificial EM).
3acec69a94eaaf Lukasz Luba 2024-03-08 636 * Therefore, check and force the drivers to provide
3acec69a94eaaf Lukasz Luba 2024-03-08 637 * power in uW.
3acec69a94eaaf Lukasz Luba 2024-03-08 638 */
3acec69a94eaaf Lukasz Luba 2024-03-08 639 if (!microwatts && !(flags & EM_PERF_DOMAIN_ARTIFICIAL)) {
3acec69a94eaaf Lukasz Luba 2024-03-08 640 dev_err(dev, "EM: only supports uW power values\n");
3acec69a94eaaf Lukasz Luba 2024-03-08 641 ret = -EINVAL;
3acec69a94eaaf Lukasz Luba 2024-03-08 642 goto unlock;
3acec69a94eaaf Lukasz Luba 2024-03-08 643 }
3acec69a94eaaf Lukasz Luba 2024-03-08 644
91362463114eb6 Lukasz Luba 2022-03-21 645 ret = em_create_pd(dev, nr_states, cb, cpus, flags);
1bc138c6229599 Lukasz Luba 2020-06-10 646 if (ret)
27871f7a8a341e Quentin Perret 2018-12-03 647 goto unlock;
27871f7a8a341e Quentin Perret 2018-12-03 648
91362463114eb6 Lukasz Luba 2022-03-21 @649 dev->em_pd->flags |= flags;
5609296750afd6 Lukasz Luba 2024-10-30 650 dev->em_pd->min_perf_state = 0;
5609296750afd6 Lukasz Luba 2024-10-30 651 dev->em_pd->max_perf_state = nr_states - 1;
c250d50fe2ce62 Lukasz Luba 2020-11-05 652
3ee7be9e10dd5f Rafael J. Wysocki 2025-03-06 653 em_table = rcu_dereference_protected(dev->em_pd->em_table,
3ee7be9e10dd5f Rafael J. Wysocki 2025-03-06 654 lockdep_is_held(&em_pd_mutex));
3ee7be9e10dd5f Rafael J. Wysocki 2025-03-06 655 em_cpufreq_update_efficiencies(dev, em_table->state);
e458716a92b57f Vincent Donnefort 2021-09-08 656
1bc138c6229599 Lukasz Luba 2020-06-10 657 em_debug_create_pd(dev);
1bc138c6229599 Lukasz Luba 2020-06-10 658 dev_info(dev, "EM: created perf domain\n");
27871f7a8a341e Quentin Perret 2018-12-03 659
27871f7a8a341e Quentin Perret 2018-12-03 660 unlock:
27871f7a8a341e Quentin Perret 2018-12-03 661 mutex_unlock(&em_pd_mutex);
e3f1164fc9ee84 Lukasz Luba 2024-02-08 662
27871f7a8a341e Quentin Perret 2018-12-03 663 return ret;
27871f7a8a341e Quentin Perret 2018-12-03 664 }
e0423541477dfb Rafael J. Wysocki 2025-09-05 665 EXPORT_SYMBOL_GPL(em_dev_register_pd_no_update);
7d9895c7fbfc9c Lukasz Luba 2020-05-27 666
:::::: The code at line 649 was first introduced by commit
:::::: 91362463114eb63ead5f02c11d58c46064c339e7 PM: EM: Use the new .get_cost() callback while registering EM
:::::: TO: Lukasz Luba <lukasz.luba@arm.com>
:::::: CC: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 3+ messages in thread* kernel/power/energy_model.c:649 em_dev_register_pd_no_update() error: we previously assumed 'dev->em_pd' could be null (see line 594)
@ 2025-12-21 22:15 kernel test robot
0 siblings, 0 replies; 3+ messages in thread
From: kernel test robot @ 2025-12-21 22:15 UTC (permalink / raw)
To: oe-kbuild; +Cc: lkp, Dan Carpenter
BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
CC: linux-kernel@vger.kernel.org
TO: "Rafael J. Wysocki" <rjw@rjwysocki.net>
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 9094662f6707d1d4b53d18baba459604e8bb0783
commit: e0423541477dfb684fbc6e6b5386054bc650f264 PM: EM: Add function for registering a PD without capacity update
date: 3 months ago
:::::: branch date: 15 hours ago
:::::: commit date: 3 months ago
config: powerpc64-randconfig-r072-20251221 (https://download.01.org/0day-ci/archive/20251222/202512220613.9bpzlxd7-lkp@intel.com/config)
compiler: powerpc64-linux-gcc (GCC) 14.3.0
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@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Closes: https://lore.kernel.org/r/202512220613.9bpzlxd7-lkp@intel.com/
smatch warnings:
kernel/power/energy_model.c:649 em_dev_register_pd_no_update() error: we previously assumed 'dev->em_pd' could be null (see line 594)
vim +649 kernel/power/energy_model.c
e0423541477dfb Rafael J. Wysocki 2025-09-05 564
e0423541477dfb Rafael J. Wysocki 2025-09-05 565 /**
e0423541477dfb Rafael J. Wysocki 2025-09-05 566 * em_dev_register_pd_no_update() - Register a perf domain for a device
e0423541477dfb Rafael J. Wysocki 2025-09-05 567 * @dev : Device to register the PD for
e0423541477dfb Rafael J. Wysocki 2025-09-05 568 * @nr_states : Number of performance states in the new PD
e0423541477dfb Rafael J. Wysocki 2025-09-05 569 * @cb : Callback functions for populating the energy model
e0423541477dfb Rafael J. Wysocki 2025-09-05 570 * @cpus : CPUs to include in the new PD (mandatory if @dev is a CPU device)
e0423541477dfb Rafael J. Wysocki 2025-09-05 571 * @microwatts : Whether or not the power values in the EM will be in uW
e0423541477dfb Rafael J. Wysocki 2025-09-05 572 *
e0423541477dfb Rafael J. Wysocki 2025-09-05 573 * Like em_dev_register_perf_domain(), but does not trigger a CPU capacity
e0423541477dfb Rafael J. Wysocki 2025-09-05 574 * update after registering the PD, even if @dev is a CPU device.
e0423541477dfb Rafael J. Wysocki 2025-09-05 575 */
e0423541477dfb Rafael J. Wysocki 2025-09-05 576 int em_dev_register_pd_no_update(struct device *dev, unsigned int nr_states,
e0423541477dfb Rafael J. Wysocki 2025-09-05 577 const struct em_data_callback *cb,
e0423541477dfb Rafael J. Wysocki 2025-09-05 578 const cpumask_t *cpus, bool microwatts)
27871f7a8a341e Quentin Perret 2018-12-03 579 {
3ee7be9e10dd5f Rafael J. Wysocki 2025-03-06 580 struct em_perf_table *em_table;
27871f7a8a341e Quentin Perret 2018-12-03 581 unsigned long cap, prev_cap = 0;
91362463114eb6 Lukasz Luba 2022-03-21 582 unsigned long flags = 0;
1bc138c6229599 Lukasz Luba 2020-06-10 583 int cpu, ret;
27871f7a8a341e Quentin Perret 2018-12-03 584
1bc138c6229599 Lukasz Luba 2020-06-10 585 if (!dev || !nr_states || !cb)
27871f7a8a341e Quentin Perret 2018-12-03 586 return -EINVAL;
27871f7a8a341e Quentin Perret 2018-12-03 587
27871f7a8a341e Quentin Perret 2018-12-03 588 /*
27871f7a8a341e Quentin Perret 2018-12-03 589 * Use a mutex to serialize the registration of performance domains and
27871f7a8a341e Quentin Perret 2018-12-03 590 * let the driver-defined callback functions sleep.
27871f7a8a341e Quentin Perret 2018-12-03 591 */
27871f7a8a341e Quentin Perret 2018-12-03 592 mutex_lock(&em_pd_mutex);
27871f7a8a341e Quentin Perret 2018-12-03 593
1bc138c6229599 Lukasz Luba 2020-06-10 @594 if (dev->em_pd) {
27871f7a8a341e Quentin Perret 2018-12-03 595 ret = -EEXIST;
27871f7a8a341e Quentin Perret 2018-12-03 596 goto unlock;
27871f7a8a341e Quentin Perret 2018-12-03 597 }
27871f7a8a341e Quentin Perret 2018-12-03 598
1bc138c6229599 Lukasz Luba 2020-06-10 599 if (_is_cpu_device(dev)) {
1bc138c6229599 Lukasz Luba 2020-06-10 600 if (!cpus) {
1bc138c6229599 Lukasz Luba 2020-06-10 601 dev_err(dev, "EM: invalid CPU mask\n");
1bc138c6229599 Lukasz Luba 2020-06-10 602 ret = -EINVAL;
1bc138c6229599 Lukasz Luba 2020-06-10 603 goto unlock;
1bc138c6229599 Lukasz Luba 2020-06-10 604 }
1bc138c6229599 Lukasz Luba 2020-06-10 605
1bc138c6229599 Lukasz Luba 2020-06-10 606 for_each_cpu(cpu, cpus) {
1bc138c6229599 Lukasz Luba 2020-06-10 607 if (em_cpu_get(cpu)) {
1bc138c6229599 Lukasz Luba 2020-06-10 608 dev_err(dev, "EM: exists for CPU%d\n", cpu);
1bc138c6229599 Lukasz Luba 2020-06-10 609 ret = -EEXIST;
1bc138c6229599 Lukasz Luba 2020-06-10 610 goto unlock;
1bc138c6229599 Lukasz Luba 2020-06-10 611 }
27871f7a8a341e Quentin Perret 2018-12-03 612 /*
1bc138c6229599 Lukasz Luba 2020-06-10 613 * All CPUs of a domain must have the same
1bc138c6229599 Lukasz Luba 2020-06-10 614 * micro-architecture since they all share the same
1bc138c6229599 Lukasz Luba 2020-06-10 615 * table.
27871f7a8a341e Quentin Perret 2018-12-03 616 */
8ec59c0f5f4966 Vincent Guittot 2019-06-17 617 cap = arch_scale_cpu_capacity(cpu);
27871f7a8a341e Quentin Perret 2018-12-03 618 if (prev_cap && prev_cap != cap) {
1bc138c6229599 Lukasz Luba 2020-06-10 619 dev_err(dev, "EM: CPUs of %*pbl must have the same capacity\n",
1bc138c6229599 Lukasz Luba 2020-06-10 620 cpumask_pr_args(cpus));
1bc138c6229599 Lukasz Luba 2020-06-10 621
27871f7a8a341e Quentin Perret 2018-12-03 622 ret = -EINVAL;
27871f7a8a341e Quentin Perret 2018-12-03 623 goto unlock;
27871f7a8a341e Quentin Perret 2018-12-03 624 }
27871f7a8a341e Quentin Perret 2018-12-03 625 prev_cap = cap;
27871f7a8a341e Quentin Perret 2018-12-03 626 }
1bc138c6229599 Lukasz Luba 2020-06-10 627 }
27871f7a8a341e Quentin Perret 2018-12-03 628
ae6ccaa650380d Lukasz Luba 2022-07-07 629 if (microwatts)
ae6ccaa650380d Lukasz Luba 2022-07-07 630 flags |= EM_PERF_DOMAIN_MICROWATTS;
91362463114eb6 Lukasz Luba 2022-03-21 631 else if (cb->get_cost)
91362463114eb6 Lukasz Luba 2022-03-21 632 flags |= EM_PERF_DOMAIN_ARTIFICIAL;
91362463114eb6 Lukasz Luba 2022-03-21 633
3acec69a94eaaf Lukasz Luba 2024-03-08 634 /*
3acec69a94eaaf Lukasz Luba 2024-03-08 635 * EM only supports uW (exception is artificial EM).
3acec69a94eaaf Lukasz Luba 2024-03-08 636 * Therefore, check and force the drivers to provide
3acec69a94eaaf Lukasz Luba 2024-03-08 637 * power in uW.
3acec69a94eaaf Lukasz Luba 2024-03-08 638 */
3acec69a94eaaf Lukasz Luba 2024-03-08 639 if (!microwatts && !(flags & EM_PERF_DOMAIN_ARTIFICIAL)) {
3acec69a94eaaf Lukasz Luba 2024-03-08 640 dev_err(dev, "EM: only supports uW power values\n");
3acec69a94eaaf Lukasz Luba 2024-03-08 641 ret = -EINVAL;
3acec69a94eaaf Lukasz Luba 2024-03-08 642 goto unlock;
3acec69a94eaaf Lukasz Luba 2024-03-08 643 }
3acec69a94eaaf Lukasz Luba 2024-03-08 644
91362463114eb6 Lukasz Luba 2022-03-21 645 ret = em_create_pd(dev, nr_states, cb, cpus, flags);
1bc138c6229599 Lukasz Luba 2020-06-10 646 if (ret)
27871f7a8a341e Quentin Perret 2018-12-03 647 goto unlock;
27871f7a8a341e Quentin Perret 2018-12-03 648
91362463114eb6 Lukasz Luba 2022-03-21 @649 dev->em_pd->flags |= flags;
5609296750afd6 Lukasz Luba 2024-10-30 650 dev->em_pd->min_perf_state = 0;
5609296750afd6 Lukasz Luba 2024-10-30 651 dev->em_pd->max_perf_state = nr_states - 1;
c250d50fe2ce62 Lukasz Luba 2020-11-05 652
3ee7be9e10dd5f Rafael J. Wysocki 2025-03-06 653 em_table = rcu_dereference_protected(dev->em_pd->em_table,
3ee7be9e10dd5f Rafael J. Wysocki 2025-03-06 654 lockdep_is_held(&em_pd_mutex));
3ee7be9e10dd5f Rafael J. Wysocki 2025-03-06 655 em_cpufreq_update_efficiencies(dev, em_table->state);
e458716a92b57f Vincent Donnefort 2021-09-08 656
1bc138c6229599 Lukasz Luba 2020-06-10 657 em_debug_create_pd(dev);
1bc138c6229599 Lukasz Luba 2020-06-10 658 dev_info(dev, "EM: created perf domain\n");
27871f7a8a341e Quentin Perret 2018-12-03 659
27871f7a8a341e Quentin Perret 2018-12-03 660 unlock:
27871f7a8a341e Quentin Perret 2018-12-03 661 mutex_unlock(&em_pd_mutex);
e3f1164fc9ee84 Lukasz Luba 2024-02-08 662
27871f7a8a341e Quentin Perret 2018-12-03 663 return ret;
27871f7a8a341e Quentin Perret 2018-12-03 664 }
e0423541477dfb Rafael J. Wysocki 2025-09-05 665 EXPORT_SYMBOL_GPL(em_dev_register_pd_no_update);
7d9895c7fbfc9c Lukasz Luba 2020-05-27 666
:::::: The code at line 649 was first introduced by commit
:::::: 91362463114eb63ead5f02c11d58c46064c339e7 PM: EM: Use the new .get_cost() callback while registering EM
:::::: TO: Lukasz Luba <lukasz.luba@arm.com>
:::::: CC: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
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