From nobody Fri Oct 3 10:13:12 2025 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 365892E229E; Wed, 3 Sep 2025 08:56:15 +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=1756889775; cv=none; b=Na+wLEajqgGv79WQ+YTnwaRPbzc6pqKa793/2jcpq6HA7480Vu8NoQzoJ6f/8lWorRpe3FaxhORh5FCOPcUzI3/2wpa/KU5woQ5XlbAy0Am1WHYnpaH9GV6MACuMbHtEKfodHxNc+BSnec6I117fK8+D9rnWbbDd+lX1pF5/+6E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756889775; c=relaxed/simple; bh=q0tHz+BMppn+t5zOxfWZIctQRwVYHLuE0UcrNZZKdo4=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=JVYMzxlpITKu8ZlvEvOhBszwFZhdRgXXK1zPtjBmtS465hXJsMQTyVwd3Z5d+MRaL98j8POYU8nmY2nnTvsmHxK+3BKawnXuWVIdLLlw1WgH5SAZz5LCMGmq/1lSeBh5ZYxHOMwBx/V/EsB/OZQz5l70jPpdFTzDQMFjy47h+EM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=NIpTPaTz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="NIpTPaTz" Received: by smtp.kernel.org (Postfix) with ESMTPS id 10859C4CEF0; Wed, 3 Sep 2025 08:56:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756889775; bh=q0tHz+BMppn+t5zOxfWZIctQRwVYHLuE0UcrNZZKdo4=; h=From:Date:Subject:To:Cc:Reply-To:From; b=NIpTPaTzzHX7kB1f8K503erRMyypAXp1ExsDMwEhyLo+dF1be4OFKtlwDQVfIIahP ESEMMz41sEaWtoKNZ03tJ9d9IJ0MiI6QaSzTeo8avGezs+TtC5yI5a30t4d4BB6v/6 O70WUoRIcXFhUmhrDmBDs88a/69IwmCC65sslg6afBp+/xZyXD8e2qAuXVJyWEsxrx CXYDyRL8LpCA4/AYREoiSV59XCl7Br2dG/n1P6aqY+OtupCCehxq1SbsjnPAu0OFKq jVjETpWA9H//y/7Wx7qZHhKDGss7GCsWGMKJCFiO0ekZAQdNIo4sEMed3DvDWI/WB4 mycw0vDRbpR5A== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id F03F0CA1009; Wed, 3 Sep 2025 08:56:14 +0000 (UTC) From: Anthony Brandon via B4 Relay Date: Wed, 03 Sep 2025 10:56:13 +0200 Subject: [PATCH v4] dmaengine: xilinx: xdma: Fix regmap max_register Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250903-xdma-max-reg-v4-1-894721175025@amarulasolutions.com> X-B4-Tracking: v=1; b=H4sIAKwCuGgC/33OywqDMBCF4VeRrJuSycVLV32P0sVooga0KYmKR Xz3RleloMv/wHzMQoLx1gRySxbizWSDda8Y8pKQqsVXY6jVsQlnXLGCAZ11j7THmXrTUEhlUaV SFULlJJ68vantvHOPZ+zWhsH5z65PsK0H0AQUaJkikyoFo0u4Y49+7DC4bhziT+FauZ5s5sTPH B6dGkXGBWaQV/rEEb8O/3NEdNQGlbnmJagDZ13XL3+nWz9DAQAA X-Change-ID: 20250901-xdma-max-reg-1649c6459358 To: Lizhi Hou , Brian Xu , Raj Kumar Rampelli , Vinod Koul , Michal Simek Cc: dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Anthony Brandon , Radhey Shyam Pandey X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=3123; i=anthony@amarulasolutions.com; h=from:subject:message-id; bh=L9Jh4ojlLzKIglwK2lLLxgJIk6sX82XB7wh+bXhzPgA=; b=owGbwMvMwCUWIi5b4HjluATjabUkhowdTGuXbz2h8O6vR9h7l8sJXDd2xeuveNJvuSdM7f7co LlBt/jiO0pZGMS4GGTFFFnKdeR5PZTrypVmPjGGmcPKBDKEgYtTACayiJHhn8qiHF9TpoxqOeMV 03eG+W0RdGx0+/VCIXcmz4H1iZdzmxgZnspOWb3hmObTayGdPPNCuJXqK/8y2R1pOFGZv0JJr9i bEwA= X-Developer-Key: i=anthony@amarulasolutions.com; a=openpgp; fpr=772C1F0D48237E772299E43354171D7041D4C718 X-Endpoint-Received: by B4 Relay for anthony@amarulasolutions.com/default with auth_id=505 X-Original-From: Anthony Brandon Reply-To: anthony@amarulasolutions.com From: Anthony Brandon The max_register field is assigned the size of the register memory region instead of the offset of the last register. The result is that reading from the regmap via debugfs can cause a segmentation fault: tail /sys/kernel/debug/regmap/xdma.1.auto/registers Unable to handle kernel paging request at virtual address ffff800082f70000 Mem abort info: ESR =3D 0x0000000096000007 EC =3D 0x25: DABT (current EL), IL =3D 32 bits SET =3D 0, FnV =3D 0 EA =3D 0, S1PTW =3D 0 FSC =3D 0x07: level 3 translation fault [...] Call trace: regmap_mmio_read32le+0x10/0x30 _regmap_bus_reg_read+0x74/0xc0 _regmap_read+0x68/0x198 regmap_read+0x54/0x88 regmap_read_debugfs+0x140/0x380 regmap_map_read_file+0x30/0x48 full_proxy_read+0x68/0xc8 vfs_read+0xcc/0x310 ksys_read+0x7c/0x120 __arm64_sys_read+0x24/0x40 invoke_syscall.constprop.0+0x64/0x108 do_el0_svc+0xb0/0xd8 el0_svc+0x38/0x130 el0t_64_sync_handler+0x120/0x138 el0t_64_sync+0x194/0x198 Code: aa1e03e9 d503201f f9400000 8b214000 (b9400000) Reviewed-by: Lizhi Hou Reviewed-by: Radhey Shyam Pandey ---[ end trace 0000000000000000 ]--- note: tail[1217] exited with irqs disabled note: tail[1217] exited with preempt_count 1 Segmentation fault Fixes: 17ce252266c7 ("dmaengine: xilinx: xdma: Add xilinx xdma driver") Signed-off-by: Anthony Brandon Reviewed-by: Lizhi Hou Reviewed-by: Radhey Shyam Pandey --- Changes in v4: - Reorder Reviewed-by - Link to v3: https://lore.kernel.org/r/20250902-xdma-max-reg-v3-1-5fa37b8d= 2b15@amarulasolutions.com Changes in v3: - Add Fixes tag - Link to v2: https://lore.kernel.org/r/20250901-xdma-max-reg-v2-1-fa3723a7= 18cd@amarulasolutions.com Changes in v2: - Define new constant XDMA_MAX_REG_OFFSET and use that. - Link to v1: https://lore.kernel.org/r/20250901-xdma-max-reg-v1-1-b6a04561= edb1@amarulasolutions.com --- drivers/dma/xilinx/xdma-regs.h | 1 + drivers/dma/xilinx/xdma.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/dma/xilinx/xdma-regs.h b/drivers/dma/xilinx/xdma-regs.h index 6ad08878e93862b770febb71b8bc85e66813428e..70bca92621aa41b0367d1e236b3= e276344a26320 100644 --- a/drivers/dma/xilinx/xdma-regs.h +++ b/drivers/dma/xilinx/xdma-regs.h @@ -9,6 +9,7 @@ =20 /* The length of register space exposed to host */ #define XDMA_REG_SPACE_LEN 65536 +#define XDMA_MAX_REG_OFFSET (XDMA_REG_SPACE_LEN - 4) =20 /* * maximum number of DMA channels for each direction: diff --git a/drivers/dma/xilinx/xdma.c b/drivers/dma/xilinx/xdma.c index 0d88b1a670e142dac90d09c515809faa2476a816..5ecf8223c112e468c79ce635398= ba393a535b9e0 100644 --- a/drivers/dma/xilinx/xdma.c +++ b/drivers/dma/xilinx/xdma.c @@ -38,7 +38,7 @@ static const struct regmap_config xdma_regmap_config =3D { .reg_bits =3D 32, .val_bits =3D 32, .reg_stride =3D 4, - .max_register =3D XDMA_REG_SPACE_LEN, + .max_register =3D XDMA_MAX_REG_OFFSET, }; =20 /** --- base-commit: b320789d6883cc00ac78ce83bccbfe7ed58afcf0 change-id: 20250901-xdma-max-reg-1649c6459358 Best regards, --=20 Anthony Brandon