scsi: ufs: core: Ensure clk_gating.lock is used only after initializa…

…tion

commit 3d4114a upstream.

Address 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 torvalds#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().  Do that
unconditionally as initializing a spinlock is a fast operation.

Fixes: 209f4e4 ("scsi: ufs: core: Introduce a new clock_gating lock")
Reported-by: Dmitry Baryshkov <[email protected]>
Tested-by: Geert Uytterhoeven <[email protected]>
Signed-off-by: Avri Altman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Bean Huo <[email protected]>
Reviewed-by: Bart Van Assche <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

drivers/ufs/core/ufshcd.c

@@ -2150,8 +2150,6 @@ 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);
@@ -10453,6 +10451,12 @@ 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()
+	 */
+	spin_lock_init(&hba->clk_gating.lock);
+
 	err = ufshcd_hba_init(hba);
 	if (err)
 		goto out_error;