From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 3E1D18F57 for ; Sun, 16 Jul 2023 20:51:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 684A4C433C7; Sun, 16 Jul 2023 20:51:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1689540691; bh=bYu5xYqkgGLkR2u921pFEK17Nkwd0nNAFAYva1ybE6s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IscSxCugctneibqY4B7M2YtI69eYob1rw3CNO2aFlA26G1wnBdakWYJbIWfqsp+hx PjderMHxHLpm4MNafq3+JXHf4N/HDAdpoThd2ukUFmPOXhXxIExc0X6ZhWa3E4WOSG nQ05lOGko31IZvETVkN+FcV9IFVISI/U6JhJErGk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jonathan Cameron , Yicong Yang , Suzuki K Poulose , Sasha Levin Subject: [PATCH 6.1 453/591] hwtracing: hisi_ptt: Fix potential sleep in atomic context Date: Sun, 16 Jul 2023 21:49:52 +0200 Message-ID: <20230716194935.628588593@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230716194923.861634455@linuxfoundation.org> References: <20230716194923.861634455@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Yicong Yang [ Upstream commit 6c50384ef8b94a527445e3694ae6549e1f15d859 ] We're using pci_irq_vector() to obtain the interrupt number and then bind it to the CPU start perf under the protection of spinlock in pmu::start(). pci_irq_vector() might sleep since [1] because it will call msi_domain_get_virq() to get the MSI interrupt number and it needs to acquire dev->msi.data->mutex. Getting a mutex will sleep on contention. So use pci_irq_vector() in an atomic context is problematic. This patch cached the interrupt number in the probe() and uses the cached data instead to avoid potential sleep. [1] commit 82ff8e6b78fc ("PCI/MSI: Use msi_get_virq() in pci_get_vector()") Fixes: ff0de066b463 ("hwtracing: hisi_ptt: Add trace function support for HiSilicon PCIe Tune and Trace device") Reviewed-by: Jonathan Cameron Signed-off-by: Yicong Yang Signed-off-by: Suzuki K Poulose Link: https://lore.kernel.org/r/20230621092804.15120-6-yangyicong@huawei.com Signed-off-by: Sasha Levin --- drivers/hwtracing/ptt/hisi_ptt.c | 12 +++++------- drivers/hwtracing/ptt/hisi_ptt.h | 2 ++ 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c index 30f1525639b57..4140efd664097 100644 --- a/drivers/hwtracing/ptt/hisi_ptt.c +++ b/drivers/hwtracing/ptt/hisi_ptt.c @@ -341,13 +341,13 @@ static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt) if (ret < 0) return ret; - ret = devm_request_threaded_irq(&pdev->dev, - pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), + hisi_ptt->trace_irq = pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ); + ret = devm_request_threaded_irq(&pdev->dev, hisi_ptt->trace_irq, NULL, hisi_ptt_isr, 0, DRV_NAME, hisi_ptt); if (ret) { pci_err(pdev, "failed to request irq %d, ret = %d\n", - pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), ret); + hisi_ptt->trace_irq, ret); return ret; } @@ -757,8 +757,7 @@ static void hisi_ptt_pmu_start(struct perf_event *event, int flags) * core in event_function_local(). If CPU passed is offline we'll fail * here, just log it since we can do nothing here. */ - ret = irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ), - cpumask_of(cpu)); + ret = irq_set_affinity(hisi_ptt->trace_irq, cpumask_of(cpu)); if (ret) dev_warn(dev, "failed to set the affinity of trace interrupt\n"); @@ -1018,8 +1017,7 @@ static int hisi_ptt_cpu_teardown(unsigned int cpu, struct hlist_node *node) * Also make sure the interrupt bind to the migrated CPU as well. Warn * the user on failure here. */ - if (irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ), - cpumask_of(target))) + if (irq_set_affinity(hisi_ptt->trace_irq, cpumask_of(target))) dev_warn(dev, "failed to set the affinity of trace interrupt\n"); hisi_ptt->trace_ctrl.on_cpu = target; diff --git a/drivers/hwtracing/ptt/hisi_ptt.h b/drivers/hwtracing/ptt/hisi_ptt.h index 5beb1648c93ab..948a4c4231527 100644 --- a/drivers/hwtracing/ptt/hisi_ptt.h +++ b/drivers/hwtracing/ptt/hisi_ptt.h @@ -166,6 +166,7 @@ struct hisi_ptt_pmu_buf { * @pdev: pci_dev of this PTT device * @tune_lock: lock to serialize the tune process * @pmu_lock: lock to serialize the perf process + * @trace_irq: interrupt number used by trace * @upper_bdf: the upper BDF range of the PCI devices managed by this PTT device * @lower_bdf: the lower BDF range of the PCI devices managed by this PTT device * @port_filters: the filter list of root ports @@ -180,6 +181,7 @@ struct hisi_ptt { struct pci_dev *pdev; struct mutex tune_lock; spinlock_t pmu_lock; + int trace_irq; u32 upper_bdf; u32 lower_bdf; -- 2.39.2