From patchwork Sun Jan 26 06:45:20 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Avri Altman X-Patchwork-Id: 860803 Received: from esa5.hgst.iphmx.com (esa5.hgst.iphmx.com [216.71.153.144]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9BC9D645; Sun, 26 Jan 2025 06:48:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.71.153.144 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737874111; cv=none; b=rvGupJfgFCCZud0uu534MRV7gMVU4Q0GviW81m+H8nMVzWHu+tYPkWdC+C6vBx5JpdacGIf/EqQl7Yng6HUNpljFv2PgaX/g7KrdeabNPwE0fUPMgs1KyUe3LdU8Qu66aqaACxr1PDre5rPwpChWegX+LBET9emOwQRK/n1GlTk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737874111; c=relaxed/simple; bh=E9iw3JaNK8Hvxxzw45ObpZZqmzDbVTsBLJjyGar2Wms=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=T/RI+hW5nFXw6rlqaQhqjNR/RGuS5cq6Cfwf55BrvWg3zOpKYipYl3iOl7vjDogeXDSzBq5qTxcnCmYjmCiKISwiA3+xwDRqflaJgw3mnmty0Wt/a70ufRU6ZPM58BNu2N9ROFZJgJbO09zvL3X6KxX57wLT0lw/RA6ewxH49w0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=wdc.com; spf=pass smtp.mailfrom=wdc.com; dkim=pass (2048-bit key) header.d=wdc.com header.i=@wdc.com header.b=Abd8A5yy; arc=none smtp.client-ip=216.71.153.144 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=wdc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=wdc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=wdc.com header.i=@wdc.com header.b="Abd8A5yy" DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1737874109; x=1769410109; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=E9iw3JaNK8Hvxxzw45ObpZZqmzDbVTsBLJjyGar2Wms=; b=Abd8A5yy/VJ7IO+SGB6ObO7qVQ2gzkaDhGKP7KyTLa4/d/mAvjuyvVgo Ldz+YICVVWcy1sVGJlpJk1l+t2spS3VcrCrUSvgjuP0H1qxAcx9BunSG0 jDC6OP8Pdn27+RgV0L6O1FosR6PfCO1D8o3xQ8ZcukHzt0/Y5VEU40ZPU zlkVCCD3UIGMK7hP+dtih+Lna4tc1VvMZtU46EDP8k0B8Yspy1J8j2aqj pM/aAWMdjq6YIPaVT9e5cNRF1sWoEuv3uzctQLfkT9aN4QumwdauHPb18 dvj5i5+tgO56IKP97YH5XDBwcEAuYTFVaBb4JEDPx59fuIMLaR8h+EFXa g==; X-CSE-ConnectionGUID: 9DHs8PewRAWdaD+nSTgDvw== X-CSE-MsgGUID: oM4nGf8zTiW07IWlB0bXTA== X-IronPort-AV: E=Sophos;i="6.13,235,1732550400"; d="scan'208";a="37833294" Received: from uls-op-cesaip01.wdc.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 26 Jan 2025 14:48:23 +0800 IronPort-SDR: 6795cd1b_/NSAKl0lDNAlIsJsYYgwMzwHNaiKl1T20fzJRgkPvkdCduX B+Dg1a09t07lnWK2+53RFL6iKS48CL7CTfcVbBg== Received: from uls-op-cesaip01.wdc.com ([10.248.3.36]) by uls-op-cesaep01.wdc.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 25 Jan 2025 21:50:19 -0800 WDCIronportException: Internal Received: from avri-office.ad.shared (HELO avri-office.sdcorp.global.sandisk.com) ([10.45.31.142]) by uls-op-cesaip01.wdc.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 25 Jan 2025 22:48:21 -0800 From: Avri Altman To: "Martin K . Petersen" Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Manivannan Sadhasivam , Bart Van Assche , Geert Uytterhoeven , Avri Altman , Dmitry Baryshkov Subject: [PATCH v3 1/2] scsi: ufs: core: Ensure clk_gating.lock is used only after initialization Date: Sun, 26 Jan 2025 08:45:20 +0200 Message-Id: <20250126064521.3857557-2-avri.altman@wdc.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20250126064521.3857557-1-avri.altman@wdc.com> References: <20250126064521.3857557-1-avri.altman@wdc.com> Precedence: bulk X-Mailing-List: linux-scsi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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`. Do that unconditionally as initializing a spinlock is a fast operation. Fixes: 209f4e43b806 ("scsi: ufs: core: Introduce a new clock_gating lock") Reported-by: Dmitry Baryshkov Signed-off-by: Avri Altman --- drivers/ufs/core/ufshcd.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index f6c38cf10382..b73c87da383d 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 +10410,12 @@ 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; From patchwork Sun Jan 26 06:45:21 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Avri Altman X-Patchwork-Id: 860120 Received: from esa2.hgst.iphmx.com (esa2.hgst.iphmx.com [68.232.143.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6EBED70839; Sun, 26 Jan 2025 06:48:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=68.232.143.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737874117; cv=none; b=XtC02gL+VMdYruYuCOFlp838psqOOO43dDRZJuZ7bgcTsu/80HH6AoBr6b9L6M/9bQuPUU0Iqu5cji7vuLdc2WQZ3z/eUe/DxBPD++BTA5ZrhE//asjMA0cSyYJyeyPGJ0KgH5qSD38DlzqKaFePX7twNWNqscEyZ0KvHYl8jG0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737874117; c=relaxed/simple; bh=d19W+FapVGrIgQjfm3lNAjqHEF57wreNHedB3RFpZY4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Tcm/2bksO1aNofJLaUlbk0tffBPG2+DPP9a+/piZKX+9nwRDQiFOmbP5loxrEi46SEzurYXZXUEXwXoBSPzLFDZaWmSLSfe9SOfxwr5jQOZFkyBUpUIPu/hC71l49HKQZcyWBs+2W9P/qoqeZ8CS7KvUZZXNti/fVJJxr7yJZjc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=wdc.com; spf=pass smtp.mailfrom=wdc.com; dkim=pass (2048-bit key) header.d=wdc.com header.i=@wdc.com header.b=eoT0watW; arc=none smtp.client-ip=68.232.143.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=wdc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=wdc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=wdc.com header.i=@wdc.com header.b="eoT0watW" DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1737874115; x=1769410115; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=d19W+FapVGrIgQjfm3lNAjqHEF57wreNHedB3RFpZY4=; b=eoT0watWp9g93dyENtY5F4Nb6AETHJPimunXjb/hVsi+sccsRDNRMmH9 jBdnVn2H+LlbsSeq1jMZr7lVIuBqpE8e0Y7C/U0u8mBvy/6Urjm4i2wGy C11d4EVzLbgNKti5cpl6sZPThlguXS5OtRAq8LTfLBLIYUZl2LD2NTslu n69d4fD9Fzbrr7tVgnbCDoVl0JQYaTWOjTW8bHFqBcAwEuIcYzWnyLmJd Mx0y3BUkGfYegu4hYcA7B8xS+ctPSFgicvu47+BsMgsC3uM/6075iIXw7 1gJFmzjbm3e9iO8GCxAJqQ5Aau5eTIvPsBDy7Tgdt66Jttx86WzXoUst+ w==; X-CSE-ConnectionGUID: q4SEr/DiTyKNPu81Vipurw== X-CSE-MsgGUID: 5VfNDJwNR9KPVbNi2YhMOw== X-IronPort-AV: E=Sophos;i="6.13,235,1732550400"; d="scan'208";a="37344168" Received: from uls-op-cesaip01.wdc.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 26 Jan 2025 14:48:34 +0800 IronPort-SDR: 6795cd26_cbGJzkz8wAG+BExxANnKap0Xb73nXH288r+120eEGgw6PRz JG18iHGEzevgqD2OjpfQBBSXhDEFcUIWcdZj4xA== Received: from uls-op-cesaip01.wdc.com ([10.248.3.36]) by uls-op-cesaep01.wdc.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 25 Jan 2025 21:50:30 -0800 WDCIronportException: Internal Received: from avri-office.ad.shared (HELO avri-office.sdcorp.global.sandisk.com) ([10.45.31.142]) by uls-op-cesaip01.wdc.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 25 Jan 2025 22:48:33 -0800 From: Avri Altman To: "Martin K . Petersen" Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Manivannan Sadhasivam , Bart Van Assche , Geert Uytterhoeven , Avri Altman Subject: [PATCH v3 2/2] scsi: ufs: Fix toggling of clk_gating.state when clock gating is not allowed Date: Sun, 26 Jan 2025 08:45:21 +0200 Message-Id: <20250126064521.3857557-3-avri.altman@wdc.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20250126064521.3857557-1-avri.altman@wdc.com> References: <20250126064521.3857557-1-avri.altman@wdc.com> Precedence: bulk X-Mailing-List: linux-scsi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 This commit addresses an issue where `clk_gating.state` is being toggled in `ufshcd_setup_clocks` even if clock gating is not allowed. This can lead to a crash with the following error: BUG: spinlock bad magic on CPU#6, swapper/0/1 lock: 0xffffff84443014e8, .magic: 00000000, .owner: /-1, .owner_cpu: 0 CPU: 6 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.13.0-rcar3-initrd-08318-g75abbef32a94 #896 Hardware name: R-Car S4 Starter Kit board (DT) Call trace: show_stack+0x18/0x24 (C) dump_stack_lvl+0x60/0x80 dump_stack+0x18/0x24 spin_bug+0x7c/0xa0 do_raw_spin_lock+0x34/0xb4 _raw_spin_lock_irqsave+0x1c/0x30 class_spinlock_irqsave_constructor+0x18/0x30 ufshcd_setup_clocks+0x98/0x23c ufshcd_init+0x288/0xd38 ufshcd_pltfrm_init+0x618/0x738 ufs_renesas_probe+0x18/0x24 platform_probe+0x68/0xb8 really_probe+0x138/0x268 __driver_probe_device+0xf4/0x10c driver_probe_device+0x3c/0xf8 __driver_attach+0xf0/0x100 bus_for_each_dev+0x84/0xdc driver_attach+0x24/0x30 bus_add_driver+0xe8/0x1dc driver_register+0xbc/0xf8 __platform_driver_register+0x24/0x30 ufs_renesas_platform_init+0x1c/0x28 do_one_initcall+0x84/0x1f4 kernel_init_freeable+0x238/0x23c kernel_init+0x20/0x120 ret_from_fork+0x10/0x20 The root cause of the issue is that `clk_gating.state` is being toggled even if clock gating is not allowed. This can lead to the spinlock being used before it is properly initialized. The fix is to add a check for `hba->clk_gating.is_initialized` before toggling `clk_gating.state` in `ufshcd_setup_clocks`. Since `clk_gating.lock` is now initialized unconditionally, this is for documentation purposes, to ensure clarity in the code. The primary fix remains to prevent toggling the `clk_gating.state` if clock gating is not allowed. Fixes: 1ab27c9cf8b6 ("ufs: Add support for clock gating") Reported-by: Geert Uytterhoeven Signed-off-by: Avri Altman Tested-by: Geert Uytterhoeven --- drivers/ufs/core/ufshcd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index b73c87da383d..abe0774133f5 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -9140,7 +9140,7 @@ static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on) if (!IS_ERR_OR_NULL(clki->clk) && clki->enabled) clk_disable_unprepare(clki->clk); } - } else if (!ret && on) { + } else if (!ret && on && hba->clk_gating.is_initialized) { scoped_guard(spinlock_irqsave, &hba->clk_gating.lock) hba->clk_gating.state = CLKS_ON; trace_ufshcd_clk_gating(dev_name(hba->dev),