The following BUG was triggered:
=============================
[ BUG: Invalid wait context ]
6.12.0-rc2-XXX #406 Not tainted
-----------------------------
kworker/1:1/62 is trying to lock:
ffffff8801593030 (&cpc_ptr->rmw_lock){+.+.}-{3:3}, at: cpc_write+0xcc/0x370
other info that might help us debug this:
context-{5:5}
2 locks held by kworker/1:1/62:
#0: ffffff897ef5ec98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2c/0x50
#1: ffffff880154e238 (&sg_policy->update_lock){....}-{2:2}, at: sugov_update_shared+0x3c/0x280
stack backtrace:
CPU: 1 UID: 0 PID: 62 Comm: kworker/1:1 Not tainted 6.12.0-rc2-g9654bd3e8806 #406
Workqueue: 0x0 (events)
Call trace:
dump_backtrace+0xa4/0x130
show_stack+0x20/0x38
dump_stack_lvl+0x90/0xd0
dump_stack+0x18/0x28
__lock_acquire+0x480/0x1ad8
lock_acquire+0x114/0x310
_raw_spin_lock+0x50/0x70
cpc_write+0xcc/0x370
cppc_set_perf+0xa0/0x3a8
cppc_cpufreq_fast_switch+0x40/0xc0
cpufreq_driver_fast_switch+0x4c/0x218
sugov_update_shared+0x234/0x280
update_load_avg+0x6ec/0x7b8
dequeue_entities+0x108/0x830
dequeue_task_fair+0x58/0x408
__schedule+0x4f0/0x1070
schedule+0x54/0x130
worker_thread+0xc0/0x2e8
kthread+0x130/0x148
ret_from_fork+0x10/0x20
sugov_update_shared() locks a raw_spinlock while cpc_write() locks a
spinlock.
To have a correct wait-type order, update rmw_lock to a raw spinlock and
ensure that interrupts will be disabled on the CPU holding it.
Fixes: 60949b7b8054 ("ACPI: CPPC: Fix MASK_VAL() usage")
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Link: https://patch.msgid.link/20241028125657.1271512-1-pierre.gondois@arm.com
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
1c10941e34