From nobody Wed Feb 11 06:54:00 2026 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 1687E2D239A; Tue, 2 Sep 2025 17:19:28 +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=1756833569; cv=none; b=uSfsEqS8nABs9I1VNlOIfNsxFHUF0D/4ZAezrQqDXhdWe4cbay7adLn6FsOYe5gDDcgr8N2diVsXnBxQpKvjbU8eil7WaZB/K2RL8DjtH+MRU2AY+N3ejCCWas37HOP1psmoyco3Nc3jTxBlPQVbShvBKY5XP3XlnfvlDkAt4Zg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756833569; c=relaxed/simple; bh=HpkXJYlU3KxliNdCAuU+x9yMGw6xejBlZCkOpmaJSX8=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=BUn02SrQyzQAp34x4j0XHU8kIy+Vq3Bh7+E7kw5DpSGfV30MlPZway3BGrBgJeiBJKSpJJGCUlFZo7mDwVJ9ZIH1gGmMTRkorYOSqsyX62oExKLazbrBw4VHFRDr6UTV2qXiievXrIHVf7/89YaQxLCPPwCdw5WRWlZa9on1Xug= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=K+lsjhki; 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="K+lsjhki" Received: by smtp.kernel.org (Postfix) with ESMTPS id 953F3C4CEED; Tue, 2 Sep 2025 17:19:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756833568; bh=HpkXJYlU3KxliNdCAuU+x9yMGw6xejBlZCkOpmaJSX8=; h=From:Date:Subject:To:Cc:Reply-To:From; b=K+lsjhkiuVCel0yGpRoQlPkb5BKVV1HrSoE9pNqKNGX/0yQqZCcjJRK6YIS+gg0bD yhrSEDC9jMg4CkRdmehR2CZpXGpqkL2dgwjMVvD9JNlFPSl0Viu0Ma2dwFd0tJ9xJI hV27pX7L95NSy+T67QGTBvtNH2HI2r8yOArjN9d1Y4hh4UNIe4l5LcRomOySbz+jwq Kb9VD2irbbJQ3nuO8hiFwDl77I8ctH4myexOee9rKD6yuFjvcnslzdIFie8JRt3VUC yGv+CXQn5vRA4jARjMcc5xtOhc81W6HoJNlX0O5l8SZqWautWzYx0u5UL2u7uoDG1Y GAbvI3YZ2qCmQ== 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 8295ACA1007; Tue, 2 Sep 2025 17:19:28 +0000 (UTC) From: Anthony Brandon via B4 Relay Date: Tue, 02 Sep 2025 19:19:08 +0200 Subject: [PATCH v3] 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: <20250902-xdma-max-reg-v3-1-5fa37b8d2b15@amarulasolutions.com> X-B4-Tracking: v=1; b=H4sIAAsnt2gC/33OTQ6DIBCG4asY1qXhR1C76j2aLkZAJRFpQImN8 e5F93b5fsk8mQ1FE6yJ6FFsKJhko/VTDn4rkBpg6g22OjdihAnSEIpX7QA7WHEwPaaybJQsRcN FjfLJJ5jOrif3eucebJx9+J56osd6ASWKKW4lkFJIanRLn+AgLCNEPy5z/inelXfoMBP757Dsd MArxqGitdIXzr7vP5y9ZwP7AAAA 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 X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=2916; i=anthony@amarulasolutions.com; h=from:subject:message-id; bh=RXW5CKC0f3s39M0SO5bLPVh0482yL+nz0tdpgoq7TKU=; b=owGbwMvMwCUWIi5b4HjluATjabUkhozt6vJT3T+IRyk+FS/t+zKd0+9zxrw96yOMjUTfNtiLx 7ntUJLrKGVhEONikBVTZCnXkef1UK4rV5r5xBhmDisTyBAGLk4BmMgbb0aGPydEFERjPZZpfez2 a1cXOvrz1Z/+j1Zqp16f/8h96GywCMP/ahtnt8clNz3rnVqZ9DaUxkuf9V/37NmZd45JjtI7q1I ZAQ== 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 ---[ 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") Reviewed-by: Lizhi Hou Signed-off-by: Anthony Brandon --- 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