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[2001:1868:205::9]) by mx.google.com with ESMTPS id d89si4055843pfj.146.2016.02.02.13.17.29 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 02 Feb 2016 13:17:29 -0800 (PST) Received-SPF: pass (google.com: domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) client-ip=2001:1868:205::9; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) smtp.mailfrom=linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org; dkim=neutral (body hash did not verify) header.i=@linaro.org Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1aQiJD-0003mz-Kk; Tue, 02 Feb 2016 21:16:23 +0000 Received: from mail-pa0-x233.google.com ([2607:f8b0:400e:c03::233]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1aQiHX-0001Df-JY for linux-arm-kernel@lists.infradead.org; Tue, 02 Feb 2016 21:14:44 +0000 Received: by mail-pa0-x233.google.com with SMTP id uo6so523336pac.1 for ; Tue, 02 Feb 2016 13:14:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=lHlIoZxfl/O9PAQlqKHkJCYvO3HP9j8lGggvJbIR9w4=; b=AVJT+C/0VkECdHqaeMqMXafEBtOJ7QOTskd4i9AhDTfuFSXHVEQ02WQky9MEss/pyB h+6R4KS/6ftD0B+SdZp4F3uG44Vcmg0XdvVoj74KfiThetmGRfNZ4mM3Z/fO3WDUfKpy qKaRkgHgsNs3hgxGSdXO+7joMK01j09CHSKrw= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=lHlIoZxfl/O9PAQlqKHkJCYvO3HP9j8lGggvJbIR9w4=; b=YZ1nvR0bEet2J41ytHv+sou2fD11DvNxNvdYuwVWO7X8whA2dGxch06TZ7w4EySQs3 GOksuy0XnQnxJZlQKSvfCmmkIOYDj+N04fTeh10xl3pKMYdU7siaQa3E0RqZKAWque+E qei3j7pSfmcZJ/nWKYLH8DNlyN4WGvGMy625hKu4W73mcqottHp0yazkfe32R5y6dhn3 hYZPU+GinscvEce+sh15kN9uJW0XqxDJR2G1QYvBl2NkboYMww41aPxKWSs2O635MEs+ WheXIHksaCeZzmiKSsJtGO+p6XCTA8iIJJZqknaLunV/pzn8SSVlhMmdeUgPLvVqmgas Cfig== X-Gm-Message-State: AG10YOTGw1/kf2PYYZJ7YQNlQkYzv0T3bNc0j3j03xqvqFsdak4qSA9Gz4m9XzyczaQAs7TD X-Received: by 10.66.250.165 with SMTP id zd5mr49413180pac.111.1454447660800; Tue, 02 Feb 2016 13:14:20 -0800 (PST) Received: from t430.cg.shawcable.net ([184.64.168.246]) by smtp.gmail.com with ESMTPSA id 79sm4769141pfr.22.2016.02.02.13.14.19 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 02 Feb 2016 13:14:20 -0800 (PST) From: Mathieu Poirier To: gregkh@linuxfoundation.org Subject: [PATCH 6/7] coresight: removing bind/unbind options from sysfs Date: Tue, 2 Feb 2016 14:14:00 -0700 Message-Id: <1454447641-29153-7-git-send-email-mathieu.poirier@linaro.org> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1454447641-29153-1-git-send-email-mathieu.poirier@linaro.org> References: <1454447641-29153-1-git-send-email-mathieu.poirier@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160202_131439_854883_238D62AF X-CRM114-Status: GOOD ( 16.03 ) X-Spam-Score: -2.7 (--) X-Spam-Report: SpamAssassin version 3.4.0 on bombadil.infradead.org summary: Content analysis details: (-2.7 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [2607:f8b0:400e:c03:0:0:0:233 listed in] [list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org The coresight drivers have absolutely no control over bind and unbind operations triggered from sysfs. The operations simply can't be cancelled or denied event when one or several tracing sessions are under way. Since the memory associated to individual device is invariably freed, the end result is a kernel crash when the path from source to sink is travelled again as demonstrated here[1]. One solution could be to keep track of all the path (i.e tracing session) that get created and iterate through the elements of those path looking for the coresight device that is being removed. This proposition doesn't scale well since there is no upper bound on the amount of concurrent trace session that can be created. With the above in mind, this patch prevent devices from being unbounded from their driver by using the driver->suppress_bind_attr option. That way trace sessions can be managed without fearing to loose devices. Since device can't be removed anymore the xyz_remove() functions found in each driver is also removed. [1]. http://www.spinics.net/lists/arm-kernel/msg474952.html Reported-by: Rabin Vincent Signed-off-by: Mathieu Poirier --- drivers/hwtracing/coresight/coresight-etb10.c | 11 +---------- drivers/hwtracing/coresight/coresight-etm3x.c | 13 +------------ drivers/hwtracing/coresight/coresight-etm4x.c | 13 +------------ drivers/hwtracing/coresight/coresight-funnel.c | 10 +--------- drivers/hwtracing/coresight/coresight-replicator-qcom.c | 11 +---------- drivers/hwtracing/coresight/coresight-replicator.c | 16 +--------------- drivers/hwtracing/coresight/coresight-tmc.c | 15 +-------------- drivers/hwtracing/coresight/coresight-tpiu.c | 10 +--------- 8 files changed, 8 insertions(+), 91 deletions(-) -- 2.1.4 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c index 77d0f9c1118d..92969dae739d 100644 --- a/drivers/hwtracing/coresight/coresight-etb10.c +++ b/drivers/hwtracing/coresight/coresight-etb10.c @@ -489,15 +489,6 @@ err_misc_register: return ret; } -static int etb_remove(struct amba_device *adev) -{ - struct etb_drvdata *drvdata = amba_get_drvdata(adev); - - misc_deregister(&drvdata->miscdev); - coresight_unregister(drvdata->csdev); - return 0; -} - #ifdef CONFIG_PM static int etb_runtime_suspend(struct device *dev) { @@ -537,10 +528,10 @@ static struct amba_driver etb_driver = { .name = "coresight-etb10", .owner = THIS_MODULE, .pm = &etb_dev_pm_ops, + .suppress_bind_attrs = true, }, .probe = etb_probe, - .remove = etb_remove, .id_table = etb_ids, }; diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c index d630b7ece735..5981fcc69960 100644 --- a/drivers/hwtracing/coresight/coresight-etm3x.c +++ b/drivers/hwtracing/coresight/coresight-etm3x.c @@ -1877,17 +1877,6 @@ err_arch_supported: return ret; } -static int etm_remove(struct amba_device *adev) -{ - struct etm_drvdata *drvdata = amba_get_drvdata(adev); - - coresight_unregister(drvdata->csdev); - if (--etm_count == 0) - unregister_hotcpu_notifier(&etm_cpu_notifier); - - return 0; -} - #ifdef CONFIG_PM static int etm_runtime_suspend(struct device *dev) { @@ -1948,9 +1937,9 @@ static struct amba_driver etm_driver = { .name = "coresight-etm3x", .owner = THIS_MODULE, .pm = &etm_dev_pm_ops, + .suppress_bind_attrs = true, }, .probe = etm_probe, - .remove = etm_remove, .id_table = etm_ids, }; diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c index 1ec6798b21e8..0edc10b44004 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.c +++ b/drivers/hwtracing/coresight/coresight-etm4x.c @@ -2684,17 +2684,6 @@ err_coresight_register: return ret; } -static int etm4_remove(struct amba_device *adev) -{ - struct etmv4_drvdata *drvdata = amba_get_drvdata(adev); - - coresight_unregister(drvdata->csdev); - if (--etm4_count == 0) - unregister_hotcpu_notifier(&etm4_cpu_notifier); - - return 0; -} - static struct amba_id etm4_ids[] = { { /* ETM 4.0 - Qualcomm */ .id = 0x0003b95d, @@ -2712,9 +2701,9 @@ static struct amba_id etm4_ids[] = { static struct amba_driver etm4x_driver = { .drv = { .name = "coresight-etm4x", + .suppress_bind_attrs = true, }, .probe = etm4_probe, - .remove = etm4_remove, .id_table = etm4_ids, }; diff --git a/drivers/hwtracing/coresight/coresight-funnel.c b/drivers/hwtracing/coresight/coresight-funnel.c index 2e36bde7fcb4..25e8ea140a09 100644 --- a/drivers/hwtracing/coresight/coresight-funnel.c +++ b/drivers/hwtracing/coresight/coresight-funnel.c @@ -226,14 +226,6 @@ static int funnel_probe(struct amba_device *adev, const struct amba_id *id) return 0; } -static int funnel_remove(struct amba_device *adev) -{ - struct funnel_drvdata *drvdata = amba_get_drvdata(adev); - - coresight_unregister(drvdata->csdev); - return 0; -} - #ifdef CONFIG_PM static int funnel_runtime_suspend(struct device *dev) { @@ -273,9 +265,9 @@ static struct amba_driver funnel_driver = { .name = "coresight-funnel", .owner = THIS_MODULE, .pm = &funnel_dev_pm_ops, + .suppress_bind_attrs = true, }, .probe = funnel_probe, - .remove = funnel_remove, .id_table = funnel_ids, }; diff --git a/drivers/hwtracing/coresight/coresight-replicator-qcom.c b/drivers/hwtracing/coresight/coresight-replicator-qcom.c index 584059e9e866..444815179460 100644 --- a/drivers/hwtracing/coresight/coresight-replicator-qcom.c +++ b/drivers/hwtracing/coresight/coresight-replicator-qcom.c @@ -156,15 +156,6 @@ static int replicator_probe(struct amba_device *adev, const struct amba_id *id) return 0; } -static int replicator_remove(struct amba_device *adev) -{ - struct replicator_state *drvdata = amba_get_drvdata(adev); - - pm_runtime_disable(&adev->dev); - coresight_unregister(drvdata->csdev); - return 0; -} - #ifdef CONFIG_PM static int replicator_runtime_suspend(struct device *dev) { @@ -206,9 +197,9 @@ static struct amba_driver replicator_driver = { .drv = { .name = "coresight-replicator-qcom", .pm = &replicator_dev_pm_ops, + .suppress_bind_attrs = true, }, .probe = replicator_probe, - .remove = replicator_remove, .id_table = replicator_ids, }; diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c index 963ac197c253..b77d700a3f0e 100644 --- a/drivers/hwtracing/coresight/coresight-replicator.c +++ b/drivers/hwtracing/coresight/coresight-replicator.c @@ -127,20 +127,6 @@ out_disable_pm: return ret; } -static int replicator_remove(struct platform_device *pdev) -{ - struct replicator_drvdata *drvdata = platform_get_drvdata(pdev); - - coresight_unregister(drvdata->csdev); - pm_runtime_get_sync(&pdev->dev); - if (!IS_ERR(drvdata->atclk)) - clk_disable_unprepare(drvdata->atclk); - pm_runtime_put_noidle(&pdev->dev); - pm_runtime_disable(&pdev->dev); - - return 0; -} - #ifdef CONFIG_PM static int replicator_runtime_suspend(struct device *dev) { @@ -175,11 +161,11 @@ static const struct of_device_id replicator_match[] = { static struct platform_driver replicator_driver = { .probe = replicator_probe, - .remove = replicator_remove, .driver = { .name = "coresight-replicator", .of_match_table = replicator_match, .pm = &replicator_dev_pm_ops, + .suppress_bind_attrs = true, }, }; diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c index 5b052d1e0bc6..c4fa70ed14ce 100644 --- a/drivers/hwtracing/coresight/coresight-tmc.c +++ b/drivers/hwtracing/coresight/coresight-tmc.c @@ -770,19 +770,6 @@ err_devm_kzalloc: return ret; } -static int tmc_remove(struct amba_device *adev) -{ - struct tmc_drvdata *drvdata = amba_get_drvdata(adev); - - misc_deregister(&drvdata->miscdev); - coresight_unregister(drvdata->csdev); - if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) - dma_free_coherent(drvdata->dev, drvdata->size, - drvdata->vaddr, drvdata->paddr); - - return 0; -} - static struct amba_id tmc_ids[] = { { .id = 0x0003b961, @@ -795,9 +782,9 @@ static struct amba_driver tmc_driver = { .drv = { .name = "coresight-tmc", .owner = THIS_MODULE, + .suppress_bind_attrs = true, }, .probe = tmc_probe, - .remove = tmc_remove, .id_table = tmc_ids, }; diff --git a/drivers/hwtracing/coresight/coresight-tpiu.c b/drivers/hwtracing/coresight/coresight-tpiu.c index 7214efd10db5..ca50e73d9df7 100644 --- a/drivers/hwtracing/coresight/coresight-tpiu.c +++ b/drivers/hwtracing/coresight/coresight-tpiu.c @@ -172,14 +172,6 @@ static int tpiu_probe(struct amba_device *adev, const struct amba_id *id) return 0; } -static int tpiu_remove(struct amba_device *adev) -{ - struct tpiu_drvdata *drvdata = amba_get_drvdata(adev); - - coresight_unregister(drvdata->csdev); - return 0; -} - #ifdef CONFIG_PM static int tpiu_runtime_suspend(struct device *dev) { @@ -223,9 +215,9 @@ static struct amba_driver tpiu_driver = { .name = "coresight-tpiu", .owner = THIS_MODULE, .pm = &tpiu_dev_pm_ops, + .suppress_bind_attrs = true, }, .probe = tpiu_probe, - .remove = tpiu_remove, .id_table = tpiu_ids, };