From patchwork Mon Jul 28 18:38:12 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mitchel Humpherys X-Patchwork-Id: 4636281 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 48F119F38C for ; Mon, 28 Jul 2014 18:40:58 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 442392020E for ; Mon, 28 Jul 2014 18:40:57 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 40C482012B for ; Mon, 28 Jul 2014 18:40:56 +0000 (UTC) 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 1XBpp5-0007Je-Rr; Mon, 28 Jul 2014 18:38:59 +0000 Received: from smtp.codeaurora.org ([198.145.11.231]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XBpp3-00075j-81 for linux-arm-kernel@lists.infradead.org; Mon, 28 Jul 2014 18:38:58 +0000 Received: from smtp.codeaurora.org (localhost [127.0.0.1]) by smtp.codeaurora.org (Postfix) with ESMTP id 45E421405A1; Mon, 28 Jul 2014 18:38:36 +0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 486) id 386881405A7; Mon, 28 Jul 2014 18:38:36 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from mitchelh-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: mitchelh@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 9F00A1405A1; Mon, 28 Jul 2014 18:38:35 +0000 (UTC) From: Mitchel Humpherys To: linux-arm-kernel@lists.infradead.org, iommu@lists.linux-foundation.org, Will Deacon , Russell King - ARM Linux Subject: [PATCH v2] iommu/arm-smmu: avoid calling request_irq in atomic context Date: Mon, 28 Jul 2014 11:38:12 -0700 Message-Id: <1406572692-27460-1-git-send-email-mitchelh@codeaurora.org> X-Mailer: git-send-email 2.0.1 X-Virus-Scanned: ClamAV using ClamSMTP X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140728_113857_331992_D2605862 X-CRM114-Status: GOOD ( 21.06 ) X-Spam-Score: -0.7 (/) Cc: Mitchel Humpherys X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP request_irq shouldn't be called from atomic context since it might sleep, but we're calling it with a spinlock held, resulting in: [ 9.172202] BUG: sleeping function called from invalid context at kernel/mm/slub.c:926 [ 9.182989] in_atomic(): 1, irqs_disabled(): 128, pid: 1, name: swapper/0 [ 9.189762] CPU: 1 PID: 1 Comm: swapper/0 Tainted: G W 3.10.40-gbc1b510b-38437-g55831d3bd9-dirty #97 [ 9.199757] [] (unwind_backtrace+0x0/0x11c) from [] (show_stack+0x10/0x14) [ 9.208346] [] (show_stack+0x10/0x14) from [] (kmem_cache_alloc_trace+0x3c/0x210) [ 9.217543] [] (kmem_cache_alloc_trace+0x3c/0x210) from [] (request_threaded_irq+0x88/0x11c) [ 9.227702] [] (request_threaded_irq+0x88/0x11c) from [] (arm_smmu_attach_dev+0x188/0x858) [ 9.237686] [] (arm_smmu_attach_dev+0x188/0x858) from [] (arm_iommu_attach_device+0x18/0xd0) [ 9.247837] [] (arm_iommu_attach_device+0x18/0xd0) from [] (arm_smmu_test_probe+0x68/0xd4) [ 9.257823] [] (arm_smmu_test_probe+0x68/0xd4) from [] (driver_probe_device+0x12c/0x330) [ 9.267629] [] (driver_probe_device+0x12c/0x330) from [] (__driver_attach+0x68/0x8c) [ 9.277090] [] (__driver_attach+0x68/0x8c) from [] (bus_for_each_dev+0x70/0x84) [ 9.286118] [] (bus_for_each_dev+0x70/0x84) from [] (bus_add_driver+0x100/0x244) [ 9.295233] [] (bus_add_driver+0x100/0x244) from [] (driver_register+0x9c/0x124) [ 9.304347] [] (driver_register+0x9c/0x124) from [] (arm_smmu_test_init+0x14/0x38) [ 9.313635] [] (arm_smmu_test_init+0x14/0x38) from [] (do_one_initcall+0xb8/0x160) [ 9.322926] [] (do_one_initcall+0xb8/0x160) from [] (kernel_init_freeable+0x108/0x1cc) [ 9.332564] [] (kernel_init_freeable+0x108/0x1cc) from [] (kernel_init+0xc/0xe4) [ 9.341675] [] (kernel_init+0xc/0xe4) from [] (ret_from_fork+0x14/0x3c) Fix this by moving the request_irq out of the critical section. This should be okay since smmu_domain->smmu is still being protected by the critical section. Also, we still don't program the Stream Match Register until after registering our interrupt handler so we shouldn't be missing any interrupts. Signed-off-by: Mitchel Humpherys --- Changelog: - v2: return error code from request_irq on failure --- drivers/iommu/arm-smmu.c | 37 +++++++++++++++++-------------------- 1 file changed, 17 insertions(+), 20 deletions(-) --- diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index f3f66416e2..8e17f8d2e4 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -868,7 +868,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain) static int arm_smmu_init_domain_context(struct iommu_domain *domain, struct arm_smmu_device *smmu) { - int irq, ret, start; + int ret, start; struct arm_smmu_domain *smmu_domain = domain->priv; struct arm_smmu_cfg *cfg = &smmu_domain->cfg; @@ -900,23 +900,9 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain, cfg->irptndx = cfg->cbndx; } - irq = smmu->irqs[smmu->num_global_irqs + cfg->irptndx]; - ret = request_irq(irq, arm_smmu_context_fault, IRQF_SHARED, - "arm-smmu-context-fault", domain); - if (IS_ERR_VALUE(ret)) { - dev_err(smmu->dev, "failed to request context IRQ %d (%u)\n", - cfg->irptndx, irq); - cfg->irptndx = INVALID_IRPTNDX; - goto out_free_context; - } - smmu_domain->smmu = smmu; arm_smmu_init_context_bank(smmu_domain); return 0; - -out_free_context: - __arm_smmu_free_bitmap(smmu->context_map, cfg->cbndx); - return ret; } static void arm_smmu_destroy_domain_context(struct iommu_domain *domain) @@ -1172,10 +1158,11 @@ static void arm_smmu_domain_remove_master(struct arm_smmu_domain *smmu_domain, static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) { - int ret = -EINVAL; + int irq, ret = -EINVAL; struct arm_smmu_domain *smmu_domain = domain->priv; struct arm_smmu_device *smmu; - struct arm_smmu_master_cfg *cfg; + struct arm_smmu_master_cfg *master_cfg; + struct arm_smmu_cfg *cfg = &smmu_domain->cfg; unsigned long flags; smmu = dev_get_master_dev(dev)->archdata.iommu; @@ -1203,12 +1190,22 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) } spin_unlock_irqrestore(&smmu_domain->lock, flags); + irq = smmu->irqs[smmu->num_global_irqs + cfg->irptndx]; + ret = request_irq(irq, arm_smmu_context_fault, IRQF_SHARED, + "arm-smmu-context-fault", domain); + if (IS_ERR_VALUE(ret)) { + dev_err(smmu->dev, "failed to request context IRQ %d (%u)\n", + cfg->irptndx, irq); + cfg->irptndx = INVALID_IRPTNDX; + return ret; + } + /* Looks ok, so add the device to the domain */ - cfg = find_smmu_master_cfg(smmu_domain->smmu, dev); - if (!cfg) + master_cfg = find_smmu_master_cfg(smmu_domain->smmu, dev); + if (!master_cfg) return -ENODEV; - return arm_smmu_domain_add_master(smmu_domain, cfg); + return arm_smmu_domain_add_master(smmu_domain, master_cfg); err_unlock: spin_unlock_irqrestore(&smmu_domain->lock, flags);