[PATCH v2] scsi: ufs: core: Ensure clk_gating.lock is used only after initialization
From: Avri Altman
Date: Fri Jan 24 2025 - 02:36:57 EST
This commit addresses a lockdep warning triggered by the use of the
clk_gating.lock before it is properly initialized. The warning is as
follows:
[ 4.388838] INFO: trying to register non-static key.
[ 4.395673] The code is fine but needs lockdep annotation, or maybe
[ 4.402118] you didn't initialize this object before use?
[ 4.407673] turning off the locking correctness validator.
[ 4.413334] CPU: 5 UID: 0 PID: 58 Comm: kworker/u32:1 Not tainted 6.12-rc1 #185
[ 4.413343] Hardware name: Qualcomm Technologies, Inc. Robotics RB5 (DT)
[ 4.413362] Call trace:
[ 4.413364] show_stack+0x18/0x24 (C)
[ 4.413374] dump_stack_lvl+0x90/0xd0
[ 4.413384] dump_stack+0x18/0x24
[ 4.413392] register_lock_class+0x498/0x4a8
[ 4.413400] __lock_acquire+0xb4/0x1b90
[ 4.413406] lock_acquire+0x114/0x310
[ 4.413413] _raw_spin_lock_irqsave+0x60/0x88
[ 4.413423] ufshcd_setup_clocks+0x2c0/0x490
[ 4.413433] ufshcd_init+0x198/0x10ec
[ 4.413437] ufshcd_pltfrm_init+0x600/0x7c0
[ 4.413444] ufs_qcom_probe+0x20/0x58
[ 4.413449] platform_probe+0x68/0xd8
[ 4.413459] really_probe+0xbc/0x268
[ 4.413466] __driver_probe_device+0x78/0x12c
[ 4.413473] driver_probe_device+0x40/0x11c
[ 4.413481] __device_attach_driver+0xb8/0xf8
[ 4.413489] bus_for_each_drv+0x84/0xe4
[ 4.413495] __device_attach+0xfc/0x18c
[ 4.413502] device_initial_probe+0x14/0x20
[ 4.413510] bus_probe_device+0xb0/0xb4
[ 4.413517] deferred_probe_work_func+0x8c/0xc8
[ 4.413524] process_scheduled_works+0x250/0x658
[ 4.413534] worker_thread+0x15c/0x2c8
[ 4.413542] kthread+0x134/0x200
[ 4.413550] ret_from_fork+0x10/0x20
To fix this issue, ensure that the spinlock is only used after it
has been properly initialized before using it in `ufshcd_setup_clocks`.
Fixes: 209f4e43b806 ("scsi: ufs: core: Introduce a new clock_gating lock")
Reported-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Signed-off-by: Avri Altman <avri.altman@xxxxxxx>
---
Changes since v1:
- move the spin_lock_init(&hba->clk_gating.lock) call from
ufshcd_init_clk_gating() just before the ufshcd_hba_init() call in
ufshcd_init() (Bart)
---
drivers/ufs/core/ufshcd.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index f6c38cf10382..9b17f6e2f807 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -2120,8 +2120,6 @@ static void ufshcd_init_clk_gating(struct ufs_hba *hba)
INIT_DELAYED_WORK(&hba->clk_gating.gate_work, ufshcd_gate_work);
INIT_WORK(&hba->clk_gating.ungate_work, ufshcd_ungate_work);
- spin_lock_init(&hba->clk_gating.lock);
-
hba->clk_gating.clk_gating_workq = alloc_ordered_workqueue(
"ufs_clk_gating_%d", WQ_MEM_RECLAIM | WQ_HIGHPRI,
hba->host->host_no);
@@ -10412,6 +10410,13 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
hba->irq = irq;
hba->vps = &ufs_hba_vps;
+ /*
+ * Initialize clk_gating.lock early since it is being used in
+ * ufshcd_setup_clocks()
+ */
+ if (ufshcd_is_clkgating_allowed(hba))
+ spin_lock_init(&hba->clk_gating.lock);
+
err = ufshcd_hba_init(hba);
if (err)
goto out_error;
--
2.25.1