diff options
author | Pierre Gondois <pierre.gondois@arm.com> | 2024-10-28 13:56:56 +0100 |
---|---|---|
committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2024-10-29 12:56:19 +0100 |
commit | 1c10941e34c5fdc0357e46a25bd130d9cf40b925 (patch) | |
tree | 3aff2fae586d032bf9b95ae7c0396df5ea70587c /drivers | |
parent | 81983758430957d9a5cb3333fe324fd70cf63e7e (diff) |
ACPI: CPPC: Make rmw_lock a raw_spin_lock
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>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/acpi/cppc_acpi.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index c3fc2c05d868..1a40f0514eaa 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -867,7 +867,7 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) /* Store CPU Logical ID */ cpc_ptr->cpu_id = pr->id; - spin_lock_init(&cpc_ptr->rmw_lock); + raw_spin_lock_init(&cpc_ptr->rmw_lock); /* Parse PSD data for this CPU */ ret = acpi_get_psd(cpc_ptr, handle); @@ -1087,6 +1087,7 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val) int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu); struct cpc_reg *reg = ®_res->cpc_entry.reg; struct cpc_desc *cpc_desc; + unsigned long flags; size = GET_BIT_WIDTH(reg); @@ -1126,7 +1127,7 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val) return -ENODEV; } - spin_lock(&cpc_desc->rmw_lock); + raw_spin_lock_irqsave(&cpc_desc->rmw_lock, flags); switch (size) { case 8: prev_val = readb_relaxed(vaddr); @@ -1141,7 +1142,7 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val) prev_val = readq_relaxed(vaddr); break; default: - spin_unlock(&cpc_desc->rmw_lock); + raw_spin_unlock_irqrestore(&cpc_desc->rmw_lock, flags); return -EFAULT; } val = MASK_VAL_WRITE(reg, prev_val, val); @@ -1174,7 +1175,7 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val) } if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) - spin_unlock(&cpc_desc->rmw_lock); + raw_spin_unlock_irqrestore(&cpc_desc->rmw_lock, flags); return ret_val; } |