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 69A303594D; Thu, 17 Apr 2025 18:52:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744915952; cv=none; b=GBf7iOARSmjWgdIN4zkfPe/W7FET/0/VyPEvgt/IyRP0aFolMU7NnuLhiOwswC+XyOeAhRGr/mVHMQAIdykEWOYpFPEHocR0LiIFrZGxUcOJvVNVNwWYeOT6cuwsMeRbGY3OjGSKALF0kuZHXD3erTnB7yqRnHm0/HkOS8sH7HM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744915952; c=relaxed/simple; bh=cd1y3MPmlWO5V/NrMB1sewZP0ddiVrz7bFpxF5FkYYk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sRn7AEnLCpvFDMkzfUexf6PVlpG0KPOIzJ6AuxtB3PwhxbCjXfRnII2irdOoFf59AvgiOdb0Bvf3ZVoht2K+wL0n11LRuoaDLPZN5GIHlSc9HrC6Xfl26o6jC2zn9nddDg/99zu5xV0GMev/Yg2rJPmD+vB0DKpLSaXaKbjYNj4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=wMdpGSgF; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="wMdpGSgF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C3BBEC4CEE4; Thu, 17 Apr 2025 18:52:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744915952; bh=cd1y3MPmlWO5V/NrMB1sewZP0ddiVrz7bFpxF5FkYYk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wMdpGSgFm+DdRGBHXSTS84JbkP91I50AaSQXH/NQ+9FmRcLJcL4wU8ter3WDIUblk CXKj9cwpsjOyABj8kMhNLYOm5i35wbbtlusPg7oSvcjprCkqTkd/m8FI7e6eeBCJNO FN1f1pB5Rabq+c7NBM9E7FVnwwiT67PeRjdguQyU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jason Gunthorpe , Nicolin Chen , Joerg Roedel Subject: [PATCH 6.12 295/393] iommu/tegra241-cmdqv: Fix warnings due to dmam_free_coherent() Date: Thu, 17 Apr 2025 19:51:44 +0200 Message-ID: <20250417175119.478616856@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250417175107.546547190@linuxfoundation.org> References: <20250417175107.546547190@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicolin Chen commit 767e22001dfce64cc03b7def1562338591ab6031 upstream. Two WARNINGs are observed when SMMU driver rolls back upon failure: arm-smmu-v3.9.auto: Failed to register iommu arm-smmu-v3.9.auto: probe with driver arm-smmu-v3 failed with error -22 ------------[ cut here ]------------ WARNING: CPU: 5 PID: 1 at kernel/dma/mapping.c:74 dmam_free_coherent+0xc0/0xd8 Call trace: dmam_free_coherent+0xc0/0xd8 (P) tegra241_vintf_free_lvcmdq+0x74/0x188 tegra241_cmdqv_remove_vintf+0x60/0x148 tegra241_cmdqv_remove+0x48/0xc8 arm_smmu_impl_remove+0x28/0x60 devm_action_release+0x1c/0x40 ------------[ cut here ]------------ 128 pages are still in use! WARNING: CPU: 16 PID: 1 at mm/page_alloc.c:6902 free_contig_range+0x18c/0x1c8 Call trace: free_contig_range+0x18c/0x1c8 (P) cma_release+0x154/0x2f0 dma_free_contiguous+0x38/0xa0 dma_direct_free+0x10c/0x248 dma_free_attrs+0x100/0x290 dmam_free_coherent+0x78/0xd8 tegra241_vintf_free_lvcmdq+0x74/0x160 tegra241_cmdqv_remove+0x98/0x198 arm_smmu_impl_remove+0x28/0x60 devm_action_release+0x1c/0x40 This is because the LVCMDQ queue memory are managed by devres, while that dmam_free_coherent() is called in the context of devm_action_release(). Jason pointed out that "arm_smmu_impl_probe() has mis-ordered the devres callbacks if ops->device_remove() is going to be manually freeing things that probe allocated": https://lore.kernel.org/linux-iommu/20250407174408.GB1722458@nvidia.com/ In fact, tegra241_cmdqv_init_structures() only allocates memory resources which means any failure that it generates would be similar to -ENOMEM, so there is no point in having that "falling back to standard SMMU" routine, as the standard SMMU would likely fail to allocate memory too. Remove the unwind part in tegra241_cmdqv_init_structures(), and return a proper error code to ask SMMU driver to call tegra241_cmdqv_remove() via impl_ops->device_remove(). Then, drop tegra241_vintf_free_lvcmdq() since devres will take care of that. Fixes: 483e0bd8883a ("iommu/tegra241-cmdqv: Do not allocate vcmdq until dma_set_mask_and_coherent") Cc: stable@vger.kernel.org Suggested-by: Jason Gunthorpe Signed-off-by: Nicolin Chen Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/20250407201908.172225-1-nicolinc@nvidia.com Signed-off-by: Joerg Roedel Signed-off-by: Greg Kroah-Hartman --- .../iommu/arm/arm-smmu-v3/tegra241-cmdqv.c | 32 +++---------------- 1 file changed, 5 insertions(+), 27 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c index d525ab43a4ae..dd7d030d2e89 100644 --- a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c +++ b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c @@ -487,17 +487,6 @@ static int tegra241_cmdqv_hw_reset(struct arm_smmu_device *smmu) /* VCMDQ Resource Helpers */ -static void tegra241_vcmdq_free_smmu_cmdq(struct tegra241_vcmdq *vcmdq) -{ - struct arm_smmu_queue *q = &vcmdq->cmdq.q; - size_t nents = 1 << q->llq.max_n_shift; - size_t qsz = nents << CMDQ_ENT_SZ_SHIFT; - - if (!q->base) - return; - dmam_free_coherent(vcmdq->cmdqv->smmu.dev, qsz, q->base, q->base_dma); -} - static int tegra241_vcmdq_alloc_smmu_cmdq(struct tegra241_vcmdq *vcmdq) { struct arm_smmu_device *smmu = &vcmdq->cmdqv->smmu; @@ -560,7 +549,8 @@ static void tegra241_vintf_free_lvcmdq(struct tegra241_vintf *vintf, u16 lidx) struct tegra241_vcmdq *vcmdq = vintf->lvcmdqs[lidx]; char header[64]; - tegra241_vcmdq_free_smmu_cmdq(vcmdq); + /* Note that the lvcmdq queue memory space is managed by devres */ + tegra241_vintf_deinit_lvcmdq(vintf, lidx); dev_dbg(vintf->cmdqv->dev, @@ -768,13 +758,13 @@ static int tegra241_cmdqv_init_structures(struct arm_smmu_device *smmu) vintf = kzalloc(sizeof(*vintf), GFP_KERNEL); if (!vintf) - goto out_fallback; + return -ENOMEM; /* Init VINTF0 for in-kernel use */ ret = tegra241_cmdqv_init_vintf(cmdqv, 0, vintf); if (ret) { dev_err(cmdqv->dev, "failed to init vintf0: %d\n", ret); - goto free_vintf; + return ret; } /* Preallocate logical VCMDQs to VINTF0 */ @@ -783,24 +773,12 @@ static int tegra241_cmdqv_init_structures(struct arm_smmu_device *smmu) vcmdq = tegra241_vintf_alloc_lvcmdq(vintf, lidx); if (IS_ERR(vcmdq)) - goto free_lvcmdq; + return PTR_ERR(vcmdq); } /* Now, we are ready to run all the impl ops */ smmu->impl_ops = &tegra241_cmdqv_impl_ops; return 0; - -free_lvcmdq: - for (lidx--; lidx >= 0; lidx--) - tegra241_vintf_free_lvcmdq(vintf, lidx); - tegra241_cmdqv_deinit_vintf(cmdqv, vintf->idx); -free_vintf: - kfree(vintf); -out_fallback: - dev_info(smmu->impl_dev, "Falling back to standard SMMU CMDQ\n"); - smmu->options &= ~ARM_SMMU_OPT_TEGRA241_CMDQV; - tegra241_cmdqv_remove(smmu); - return 0; } #ifdef CONFIG_IOMMU_DEBUGFS -- 2.49.0