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Rafael J. Wysocki dd509e7939 PM: EM: Address RCU-related sparse warnings

[ Upstream commit 3ee7be9e10 ]

The usage of __rcu in the Energy Model code is quite inconsistent
which causes the following sparse warnings to trigger:

kernel/power/energy_model.c:169:15: warning: incorrect type in assignment (different address spaces)
kernel/power/energy_model.c:169:15:    expected struct em_perf_table [noderef] __rcu *table
kernel/power/energy_model.c:169:15:    got struct em_perf_table *
kernel/power/energy_model.c:171:9: warning: incorrect type in argument 1 (different address spaces)
kernel/power/energy_model.c:171:9:    expected struct callback_head *head
kernel/power/energy_model.c:171:9:    got struct callback_head [noderef] __rcu *
kernel/power/energy_model.c:171:9: warning: cast removes address space '__rcu' of expression
kernel/power/energy_model.c:182:19: warning: incorrect type in argument 1 (different address spaces)
kernel/power/energy_model.c:182:19:    expected struct kref *kref
kernel/power/energy_model.c:182:19:    got struct kref [noderef] __rcu *
kernel/power/energy_model.c:200:15: warning: incorrect type in assignment (different address spaces)
kernel/power/energy_model.c:200:15:    expected struct em_perf_table [noderef] __rcu *table
kernel/power/energy_model.c:200:15:    got void *[assigned] _res
kernel/power/energy_model.c:204:20: warning: incorrect type in argument 1 (different address spaces)
kernel/power/energy_model.c:204:20:    expected struct kref *kref
kernel/power/energy_model.c:204:20:    got struct kref [noderef] __rcu *
kernel/power/energy_model.c:320:19: warning: incorrect type in argument 1 (different address spaces)
kernel/power/energy_model.c:320:19:    expected struct kref *kref
kernel/power/energy_model.c:320:19:    got struct kref [noderef] __rcu *
kernel/power/energy_model.c:325:45: warning: incorrect type in argument 2 (different address spaces)
kernel/power/energy_model.c:325:45:    expected struct em_perf_state *table
kernel/power/energy_model.c:325:45:    got struct em_perf_state [noderef] __rcu *
kernel/power/energy_model.c:425:45: warning: incorrect type in argument 3 (different address spaces)
kernel/power/energy_model.c:425:45:    expected struct em_perf_state *table
kernel/power/energy_model.c:425:45:    got struct em_perf_state [noderef] __rcu *
kernel/power/energy_model.c:442:15: warning: incorrect type in argument 1 (different address spaces)
kernel/power/energy_model.c:442:15:    expected void const *objp
kernel/power/energy_model.c:442:15:    got struct em_perf_table [noderef] __rcu *[assigned] em_table
kernel/power/energy_model.c:626:55: warning: incorrect type in argument 2 (different address spaces)
kernel/power/energy_model.c:626:55:    expected struct em_perf_state *table
kernel/power/energy_model.c:626:55:    got struct em_perf_state [noderef] __rcu *
kernel/power/energy_model.c:681:16: warning: incorrect type in assignment (different address spaces)
kernel/power/energy_model.c:681:16:    expected struct em_perf_state *new_ps
kernel/power/energy_model.c:681:16:    got struct em_perf_state [noderef] __rcu *
kernel/power/energy_model.c:699:37: warning: incorrect type in argument 2 (different address spaces)
kernel/power/energy_model.c:699:37:    expected struct em_perf_state *table
kernel/power/energy_model.c:699:37:    got struct em_perf_state [noderef] __rcu *
kernel/power/energy_model.c:733:38: warning: incorrect type in argument 3 (different address spaces)
kernel/power/energy_model.c:733:38:    expected struct em_perf_state *table
kernel/power/energy_model.c:733:38:    got struct em_perf_state [noderef] __rcu *
kernel/power/energy_model.c:855:53: warning: dereference of noderef expression
kernel/power/energy_model.c:864:32: warning: dereference of noderef expression

This is because the __rcu annotation for sparse is only applicable to
pointers that need rcu_dereference() or equivalent for protection, which
basically means pointers assigned with rcu_assign_pointer().

Make all of the above sparse warnings go away by cleaning up the usage
of __rcu and using rcu_dereference_protected() where applicable.

Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/5885405.DvuYhMxLoT@rjwysocki.net
Signed-off-by: Sasha Levin <sashal@kernel.org>

2025-05-02 08:01:30 +02:00

autosleep.c

PM: sleep: autosleep: don't include 'pm_wakeup.h' directly

2024-12-05 12:14:26 +01:00

console.c

…

energy_model.c

PM: EM: Address RCU-related sparse warnings

2025-05-02 08:01:30 +02:00

hibernate.c

PM: hibernate: Avoid deadlock in hibernate_compressor_param_set()

2025-04-20 10:22:24 +02:00