From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794047717; b=4qhjx2VBj3Xv+vW26u0p6o4QZYHNtLBDokzcefdHahxe84qgTCq0rNonJBvocumIr4sI T1fZSEeyiPtnunNFLXtlc2sHpcSF2F3JzrflcOOXePrnShbNdsG/deh1kl4AycymaurV1 NbyiSTDDthQ4ZMkdWc6ZjpAJM8Pi/L96VP5e31HxZwtLIOEjYfnFSzdxvEn9QNYI4A50K iPCYg8OA1Oz4I7g8XjS8jSuvI4rpcwmsofyPFHdEIYbsHEtZpAFb4l7qaRPxcbHJRjH5f e+e0mtH8Sjakj3k5Ynmx4ymaIzIlFh/gFD2ofnSYk312ZGJNEBj6Aalk/jU5GLv/UJw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794047717; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=5xmA5PswxYtwI7mOZ6n7GbNtOA7NumwcHYX5dsFkSKw=; b=UFzfWkQPGQpbhGzXQh80371kT4X/MZ5KmHzs6Mtk8f1G9Juq1FIonwivoXfk/6vE8qh3 H9si6BWcmTCdSdMu7RbyZRXwV4Lq9yGixC3HrhaPCWeZIQI+1pOMue4FXNsG8buz51aen Dvow7pdybTgb/rhvXLhwJomhi7yCf1AYdsh9mpnyYYg+8aYxS6flDM6gbGCkrMfMf64b4 mnYXQII+acNpRxOxqaTIV3z8PtUOgiFBig2FT+AUz97c6OxmUbxebVxIgcwOtsYhuTSCM pEMSnse1FmbCapi9cbJmg/eK4j3HfQgYwcPVo/j5skXvgwIiDSfQ3VTmwkjq7Zdg/xA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=jfmEGOC0; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 077CF606A326 for ; Sat, 7 Nov 2026 10:35:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=jfmEGOC0 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 626521F0089F; Sat, 7 Nov 2026 10:35:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794047716; bh=5xmA5PswxYtwI7mOZ6n7GbNtOA7NumwcHYX5dsFkSKw=; h=From:To:Cc:Subject:Date; b=jfmEGOC0enJ1a9GKQlf7Qri6K6yZGwkcBQZlXxPA+ZfTc6pj90EXJXa5vQP/W9rHq 8qOV+qFa+ThxTbTDEz3NGgJdbyxEfltOTISTzW5NiVwa9a6OTpqGUh9RhJYuKH3Un8 YdvqApL6Snux3l5/Ye4ZaJz6U64aufN9ZrqIybxt4+kBtPFODbHa1YRz5PVCyZztXw hjJnBWeKRI1nUBwGZjvdvqL7DICCDB9AooXcGM+BzFcQ2Q3jwh+zezT7tlJGlul3NT vlmkb0McfD4XLmczEqZ28Ax3B3Ldng91VW7MYNkMpPMtvNrbLRjHaRgx5iAul7DqdA rDheujQKp8+Zg== From: Sasha Levin To: sumit.kumar@oss.qualcomm.com, manivannan.sadhasivam@oss.qualcomm.com, bhelgaas@google.com Cc: stable@vger.kernel.org Subject: FAILED: patch "[PATCH] PCI: dwc: Set DMA_BYPASS bit in outbound IATU CTRL2 register" failed to apply to 6.6-stable tree Date: Sat, 7 Nov 2026 05:35:15 -0500 Message-ID: <20261107053515-failed-6.6-efadda401c5c@kernel.org> X-Mailer: git-send-email 2.53.0 X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x efadda401c5c8e2390ba66508eba154dbd0db5a9 # git commit -s git send-email --to '' --in-reply-to '20261107053515-failed-6.6-efadda401c5c@kernel.org' --subject-prefix 'PATCH 6.6.y' 'HEAD^..' Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From efadda401c5c8e2390ba66508eba154dbd0db5a9 Mon Sep 17 00:00:00 2001 From: Sumit Kumar Date: Tue, 8 Sep 2026 11:48:22 +0530 Subject: [PATCH] PCI: dwc: Set DMA_BYPASS bit in outbound IATU CTRL2 register An outbound iATU region matches any local (AXI/application-side) address that falls within its Base/Limit window and rewrites it to the PCIe-side address programmed in that region's Target Address Registers before the transaction goes out on the link. This matching does not distinguish CPU-initiated transactions from ones issued by the internal DMA engine (eDMA/HDMA). Example: outbound region 0 is programmed with Base/Limit covering local addresses 0x8000_0000-0x8000_0FFF and Target 0x1_0000_0000, for CPU-initiated accesses. The DMA engine is later given a descriptor whose destination is the host address 0x8000_0080, which happens to fall inside region 0's Base/Limit range. The iATU matches the DMA transaction against region 0 too and rewrites it to 0x1_0000_0080 instead of passing 0x8000_0080 through unchanged. The transaction then lands on the wrong host address, causing data corruption or an IOMMU fault when the rewritten address has no valid mapping. Set the DMA_BYPASS bit (bit 27) in PCIE_ATU_REGION_CTRL2 when programming outbound iATU regions so only CPU/AXI-initiated transactions are matched against the region; DMA engine transactions bypass the translation and go out on the PCIe link with their original address. Signed-off-by: Sumit Kumar Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260908-dma_bypass-v2-1-c3c81d408c0c@oss.qualcomm.com --- drivers/pci/controller/dwc/pcie-designware.c | 2 ++ drivers/pci/controller/dwc/pcie-designware.h | 1 + 2 files changed, 3 insertions(+) diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c index 855d2a54b3c6b..074b007dc2963 100644 --- a/drivers/pci/controller/dwc/pcie-designware.c +++ b/drivers/pci/controller/dwc/pcie-designware.c @@ -577,6 +577,8 @@ int dw_pcie_prog_outbound_atu(struct dw_pcie *pci, /* The data-less messages only for now */ val |= ATU_INHIBIT_PAYLOAD | atu->code; } + if (dw_pcie_ver_is_ge(pci, 460A)) + val |= ATU_DMA_BYPASS; dw_pcie_writel_atu_ob(pci, atu->index, ATU_REGION_CTRL2, val); /* diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h index aea474ad803cd..61e9c4e979af6 100644 --- a/drivers/pci/controller/dwc/pcie-designware.h +++ b/drivers/pci/controller/dwc/pcie-designware.h @@ -217,6 +217,7 @@ #define ATU_ENABLE BIT(31) #define ATU_BAR_MODE_ENABLE BIT(30) #define ATU_CFG_SHIFT_MODE_ENABLE BIT(28) +#define ATU_DMA_BYPASS BIT(27) #define ATU_INHIBIT_PAYLOAD BIT(22) #define ATU_FUNC_NUM_MATCH_EN BIT(19) #define ATU_LOWER_BASE 0x008 -- 2.53.0