From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D62C9C31E4B for ; Fri, 14 Jun 2019 20:38:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A9A152084D for ; Fri, 14 Jun 2019 20:38:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560544732; bh=LmF+BZd4N3RlRFjAtISVoBhuwLGTKjPaUY7TVFz+Fos=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=c+R21ZkNkry0a5bGAI27qCwFqrtX5jmN0Dhc7UWZ8qk/RsnjDj3N98fZofi+dcPiV 1MBXcYhydRtXVFofafsSRrqV5PQOKSGByg8jJG/y14l9OVh9IttnF2UcZeKfmRAsFt 8x5A6ZPZdyj/1dsyUx9vX8AQUfW0SrB6mOnNIUiE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728391AbfFNUiv (ORCPT ); Fri, 14 Jun 2019 16:38:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:50728 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726635AbfFNU3A (ORCPT ); Fri, 14 Jun 2019 16:29:00 -0400 Received: from sasha-vm.mshome.net (unknown [131.107.159.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4AA7B2184D; Fri, 14 Jun 2019 20:28:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560544139; bh=LmF+BZd4N3RlRFjAtISVoBhuwLGTKjPaUY7TVFz+Fos=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=V8lo3fQQsk/HjZtaWDs/JlpcjJwGgCrN7juTiKOIVmd/utoyG4m8eDlIT862LbiUr 6MdcnwF9jeBHssIsZnAVQ9h+SxGXhdRJPcu+DODM84Y6/TrMG1zzixFfnEtboW4IUT ssBI6XWg7P6B39S0952cTmGXzjj2b2nzb34SpeCc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Scott Wood , Wu Hao , Alan Tull , Greg Kroah-Hartman , Sasha Levin , linux-fpga@vger.kernel.org Subject: [PATCH AUTOSEL 5.1 16/59] fpga: dfl: Add lockdep classes for pdata->lock Date: Fri, 14 Jun 2019 16:28:00 -0400 Message-Id: <20190614202843.26941-16-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190614202843.26941-1-sashal@kernel.org> References: <20190614202843.26941-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Scott Wood [ Upstream commit dfe3de8d397bf878b31864d4e489d41118ec475f ] struct dfl_feature_platform_data (and it's mutex) is used by both fme and port devices, and when lockdep is enabled it complains about nesting between these locks. Tell lockdep about the difference so it can track each class separately. Here's the lockdep complaint: [ 409.680668] WARNING: possible recursive locking detected [ 409.685983] 5.1.0-rc3.fpga+ #1 Tainted: G E [ 409.691469] -------------------------------------------- [ 409.696779] fpgaconf/9348 is trying to acquire lock: [ 409.701746] 00000000a443fe2e (&pdata->lock){+.+.}, at: port_enable_set+0x24/0x60 [dfl_afu] [ 409.710006] [ 409.710006] but task is already holding lock: [ 409.715837] 0000000063b78782 (&pdata->lock){+.+.}, at: fme_pr_ioctl+0x21d/0x330 [dfl_fme] [ 409.724012] [ 409.724012] other info that might help us debug this: [ 409.730535] Possible unsafe locking scenario: [ 409.730535] [ 409.736457] CPU0 [ 409.738910] ---- [ 409.741360] lock(&pdata->lock); [ 409.744679] lock(&pdata->lock); [ 409.747999] [ 409.747999] *** DEADLOCK *** [ 409.747999] [ 409.753920] May be due to missing lock nesting notation [ 409.753920] [ 409.760704] 4 locks held by fpgaconf/9348: [ 409.764805] #0: 0000000063b78782 (&pdata->lock){+.+.}, at: fme_pr_ioctl+0x21d/0x330 [dfl_fme] [ 409.773408] #1: 00000000213c8a66 (®ion->mutex){+.+.}, at: fpga_region_program_fpga+0x24/0x200 [fpga_region] [ 409.783489] #2: 00000000fe63afb9 (&mgr->ref_mutex){+.+.}, at: fpga_mgr_lock+0x15/0x40 [fpga_mgr] [ 409.792354] #3: 000000000b2285c5 (&bridge->mutex){+.+.}, at: __fpga_bridge_get+0x26/0xa0 [fpga_bridge] [ 409.801740] [ 409.801740] stack backtrace: [ 409.806102] CPU: 45 PID: 9348 Comm: fpgaconf Kdump: loaded Tainted: G E 5.1.0-rc3.fpga+ #1 [ 409.815658] Hardware name: Intel Corporation S2600BT/S2600BT, BIOS SE5C620.86B.01.00.0763.022420181017 02/24/2018 [ 409.825911] Call Trace: [ 409.828369] dump_stack+0x5e/0x8b [ 409.831686] __lock_acquire+0xf3d/0x10e0 [ 409.835612] ? find_held_lock+0x3c/0xa0 [ 409.839451] lock_acquire+0xbc/0x1d0 [ 409.843030] ? port_enable_set+0x24/0x60 [dfl_afu] [ 409.847823] ? port_enable_set+0x24/0x60 [dfl_afu] [ 409.852616] __mutex_lock+0x86/0x970 [ 409.856195] ? port_enable_set+0x24/0x60 [dfl_afu] [ 409.860989] ? port_enable_set+0x24/0x60 [dfl_afu] [ 409.865777] ? __mutex_unlock_slowpath+0x4b/0x290 [ 409.870486] port_enable_set+0x24/0x60 [dfl_afu] [ 409.875106] fpga_bridges_disable+0x36/0x50 [fpga_bridge] [ 409.880502] fpga_region_program_fpga+0xea/0x200 [fpga_region] [ 409.886338] fme_pr_ioctl+0x13e/0x330 [dfl_fme] [ 409.890870] fme_ioctl+0x66/0xe0 [dfl_fme] [ 409.894973] do_vfs_ioctl+0xa9/0x720 [ 409.898548] ? lockdep_hardirqs_on+0xf0/0x1a0 [ 409.902907] ksys_ioctl+0x60/0x90 [ 409.906225] __x64_sys_ioctl+0x16/0x20 [ 409.909981] do_syscall_64+0x5a/0x220 [ 409.913644] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 409.918698] RIP: 0033:0x7f9d31b9b8d7 [ 409.922276] Code: 44 00 00 48 8b 05 b9 15 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 89 15 2d 00 f7 d8 64 89 01 48 [ 409.941020] RSP: 002b:00007ffe4cae0d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [ 409.948588] RAX: ffffffffffffffda RBX: 00007f9d32ade6a0 RCX: 00007f9d31b9b8d7 [ 409.955719] RDX: 00007ffe4cae0df0 RSI: 000000000000b680 RDI: 0000000000000003 [ 409.962852] RBP: 0000000000000003 R08: 00007f9d2b70a177 R09: 00007ffe4cae0e40 [ 409.969984] R10: 00007ffe4cae0160 R11: 0000000000000202 R12: 00007ffe4cae0df0 [ 409.977115] R13: 000000000000b680 R14: 0000000000000000 R15: 00007ffe4cae0f60 Signed-off-by: Scott Wood Acked-by: Wu Hao Acked-by: Alan Tull Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/fpga/dfl.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c index 2c09e502e721..c25217cde5ca 100644 --- a/drivers/fpga/dfl.c +++ b/drivers/fpga/dfl.c @@ -40,6 +40,13 @@ enum dfl_fpga_devt_type { DFL_FPGA_DEVT_MAX, }; +static struct lock_class_key dfl_pdata_keys[DFL_ID_MAX]; + +static const char *dfl_pdata_key_strings[DFL_ID_MAX] = { + "dfl-fme-pdata", + "dfl-port-pdata", +}; + /** * dfl_dev_info - dfl feature device information. * @name: name string of the feature platform device. @@ -443,11 +450,16 @@ static int build_info_commit_dev(struct build_feature_devs_info *binfo) struct platform_device *fdev = binfo->feature_dev; struct dfl_feature_platform_data *pdata; struct dfl_feature_info *finfo, *p; + enum dfl_id_type type; int ret, index = 0; if (!fdev) return 0; + type = feature_dev_id_type(fdev); + if (WARN_ON_ONCE(type >= DFL_ID_MAX)) + return -EINVAL; + /* * we do not need to care for the memory which is associated with * the platform device. After calling platform_device_unregister(), @@ -463,6 +475,8 @@ static int build_info_commit_dev(struct build_feature_devs_info *binfo) pdata->num = binfo->feature_num; pdata->dfl_cdev = binfo->cdev; mutex_init(&pdata->lock); + lockdep_set_class_and_name(&pdata->lock, &dfl_pdata_keys[type], + dfl_pdata_key_strings[type]); /* * the count should be initialized to 0 to make sure @@ -497,7 +511,7 @@ static int build_info_commit_dev(struct build_feature_devs_info *binfo) ret = platform_device_add(binfo->feature_dev); if (!ret) { - if (feature_dev_id_type(binfo->feature_dev) == PORT_ID) + if (type == PORT_ID) dfl_fpga_cdev_add_port_dev(binfo->cdev, binfo->feature_dev); else -- 2.20.1