tree:   https://git.linaro.org/people/vincent.guittot/kernel.git sched/pelt
head:   c2ebc392e23b7958705576a49091fe407b0ad7b3
commit: c2ebc392e23b7958705576a49091fe407b0ad7b3 [1/1] sched/fair: prefer prev 
cpu in asymmetric wakeup path
config: x86_64-randconfig-m001-20201026 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
Reported-by: Dan Carpenter <[email protected]>

smatch warnings:
kernel/sched/fair.c:6227 select_idle_sibling() error: uninitialized symbol 
'task_util'.

vim +/task_util +6227 kernel/sched/fair.c

772bd008cd9a1d kernel/sched/fair.c Morten Rasmussen 2016-06-22  6212  static 
int select_idle_sibling(struct task_struct *p, int prev, int target)
a50bde5130f657 kernel/sched_fair.c Peter Zijlstra   2009-11-12  6213  {
99bd5e2f245d8c kernel/sched_fair.c Suresh Siddha    2010-03-31  6214    struct 
sched_domain *sd;
c2ebc392e23b79 kernel/sched/fair.c Vincent Guittot  2020-10-21  6215    int i, 
recent_used_cpu, task_util;
                                                                                
                ^^^^^^^^^
a50bde5130f657 kernel/sched_fair.c Peter Zijlstra   2009-11-12  6216  
b7a331615d2541 kernel/sched/fair.c Morten Rasmussen 2020-02-06  6217    /*
c2ebc392e23b79 kernel/sched/fair.c Vincent Guittot  2020-10-21  6218     * On 
asymmetric system, update task utilization because we will check
c2ebc392e23b79 kernel/sched/fair.c Vincent Guittot  2020-10-21  6219     * that 
the task fits with cpu's capacity.
b7a331615d2541 kernel/sched/fair.c Morten Rasmussen 2020-02-06  6220     */
b7a331615d2541 kernel/sched/fair.c Morten Rasmussen 2020-02-06  6221    if 
(static_branch_unlikely(&sched_asym_cpucapacity)) {
c2ebc392e23b79 kernel/sched/fair.c Vincent Guittot  2020-10-21  6222            
sync_entity_load_avg(&p->se);
c2ebc392e23b79 kernel/sched/fair.c Vincent Guittot  2020-10-21  6223            
task_util = uclamp_task_util(p);
b7a331615d2541 kernel/sched/fair.c Morten Rasmussen 2020-02-06  6224    }

not initialized on else path.

b7a331615d2541 kernel/sched/fair.c Morten Rasmussen 2020-02-06  6225  
c2ebc392e23b79 kernel/sched/fair.c Vincent Guittot  2020-10-21  6226    if 
((available_idle_cpu(target) || sched_idle_cpu(target)) &&
c2ebc392e23b79 kernel/sched/fair.c Vincent Guittot  2020-10-21 @6227        
asym_fits_capacity(task_util, target))
                                                                                
               ^^^^^^^^^
uninitialized variable warning.

e0a79f529d5ba2 kernel/sched/fair.c Mike Galbraith   2013-01-28  6228            
return target;
99bd5e2f245d8c kernel/sched_fair.c Suresh Siddha    2010-03-31  6229  
99bd5e2f245d8c kernel/sched_fair.c Suresh Siddha    2010-03-31  6230    /*
97fb7a0a8944bd kernel/sched/fair.c Ingo Molnar      2018-03-03  6231     * If 
the previous CPU is cache affine and idle, don't be stupid:
a50bde5130f657 kernel/sched_fair.c Peter Zijlstra   2009-11-12  6232     */
3c29e651e16dd3 kernel/sched/fair.c Viresh Kumar     2019-06-26  6233    if 
(prev != target && cpus_share_cache(prev, target) &&
c2ebc392e23b79 kernel/sched/fair.c Vincent Guittot  2020-10-21  6234        
(available_idle_cpu(prev) || sched_idle_cpu(prev)) &&
c2ebc392e23b79 kernel/sched/fair.c Vincent Guittot  2020-10-21  6235        
asym_fits_capacity(task_util, prev))

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]

Attachment: .config.gz
Description: application/gzip

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