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 CBC35357A4A; Tue, 17 Mar 2026 17:05:15 +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=1773767115; cv=none; b=B6UPOJDtLLgYnbptOc4AUVxQgreEOKXz/0cwxe/41pYMP4V/HDDkxyTCD/e/7CaAmH62r/SGXZ18EEYxQ1H4KoyXvZ3yZggCwYj48bScmOo7Jgi6iUp4btdQdMJ1bVLdb5bVKsWIOsGrC+dEiDGF89kFjXvCMYZCBK+4voqOOK0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773767115; c=relaxed/simple; bh=VfpNCxGP85Hqk0B/64eiVbFICFC1wEr6TMO8v9Hz/kc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=O/pax8upWFDPqkYSrPXwH6IKcnGhj278Aga877a51Sjzd2iFABUsI8ouxZsTAh3ATq2fyibvp02yN4PeSM8ZChqSxNZYKEdV4gpnDhsoDSU157g+mf3ufx/BDprqkwpatU6EIP8IuiFRkOaJ/ZQZMDCds7Ihf/sZTV88untF6pQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=VP+iHi6g; 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="VP+iHi6g" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 024E1C2BCAF; Tue, 17 Mar 2026 17:05:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1773767115; bh=VfpNCxGP85Hqk0B/64eiVbFICFC1wEr6TMO8v9Hz/kc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VP+iHi6gXpE06oln2f8elDpTYAd4464/QM1tnPVHCMhx1vYf49qNtdmcCQI2uHQCr 9U+4ala1oaZDgCWgIl4WTWFAj05PvhBy0AMLT8hj4IQkrCGg++hQVqyLxkuZa1gKxf 55lLh44n5J7cmHU9trJIcxj0LqYcckztWMEsYtQY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, kernel test robot , "Christophe Leroy (CS GROUP)" , Nathan Chancellor , Madhavan Srinivasan , Sasha Levin Subject: [PATCH 6.18 018/333] powerpc/uaccess: Fix inline assembly for clang build on PPC32 Date: Tue, 17 Mar 2026 17:30:47 +0100 Message-ID: <20260317163000.035849078@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260317162959.345812316@linuxfoundation.org> References: <20260317162959.345812316@linuxfoundation.org> User-Agent: quilt/0.69 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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Christophe Leroy (CS GROUP) [ Upstream commit 0ee95a1d458630272d0415d0ffa9424fcb606c90 ] Test robot reports the following error with clang-16.0.6: In file included from kernel/rseq.c:75: include/linux/rseq_entry.h:141:3: error: invalid operand for instruction unsafe_get_user(offset, &ucs->post_commit_offset, efault); ^ include/linux/uaccess.h:608:2: note: expanded from macro 'unsafe_get_user' arch_unsafe_get_user(x, ptr, local_label); \ ^ arch/powerpc/include/asm/uaccess.h:518:2: note: expanded from macro 'arch_unsafe_get_user' __get_user_size_goto(__gu_val, __gu_addr, sizeof(*(p)), e); \ ^ arch/powerpc/include/asm/uaccess.h:284:2: note: expanded from macro '__get_user_size_goto' __get_user_size_allowed(x, ptr, size, __gus_retval); \ ^ arch/powerpc/include/asm/uaccess.h:275:10: note: expanded from macro '__get_user_size_allowed' case 8: __get_user_asm2(x, (u64 __user *)ptr, retval); break; \ ^ arch/powerpc/include/asm/uaccess.h:258:4: note: expanded from macro '__get_user_asm2' " li %1+1,0\n" \ ^ :7:5: note: instantiated into assembly here li 31+1,0 ^ 1 error generated. On PPC32, for 64 bits vars a pair of registers is used. Usually the lower register in the pair is the high part and the higher register is the low part. GCC uses r3/r4 ... r11/r12 ... r14/r15 ... r30/r31 In older kernel code inline assembly was using %1 and %1+1 to represent 64 bits values. However here it looks like clang uses r31 as high part, allthough r32 doesn't exist hence the error. Allthoug %1+1 should work, most places now use %L1 instead of %1+1, so let's do the same here. With that change, the build doesn't fail anymore and a disassembly shows clang uses r17/r18 and r31/r14 pair when GCC would have used r16/r17 and r30/r31: Disassembly of section .fixup: 00000000 <.fixup>: 0: 38 a0 ff f2 li r5,-14 4: 3a 20 00 00 li r17,0 8: 3a 40 00 00 li r18,0 c: 48 00 00 00 b c <.fixup+0xc> c: R_PPC_REL24 .text+0xbc 10: 38 a0 ff f2 li r5,-14 14: 3b e0 00 00 li r31,0 18: 39 c0 00 00 li r14,0 1c: 48 00 00 00 b 1c <.fixup+0x1c> 1c: R_PPC_REL24 .text+0x144 Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202602021825.otcItxGi-lkp@intel.com/ Fixes: c20beffeec3c ("powerpc/uaccess: Use flexible addressing with __put_user()/__get_user()") Signed-off-by: Christophe Leroy (CS GROUP) Acked-by: Nathan Chancellor Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/8ca3a657a650e497a96bfe7acde2f637dadab344.1770103646.git.chleroy@kernel.org Signed-off-by: Sasha Levin --- arch/powerpc/include/asm/uaccess.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h index 3987a5c33558b..929f7050c73a6 100644 --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -253,7 +253,7 @@ __gus_failed: \ ".section .fixup,\"ax\"\n" \ "4: li %0,%3\n" \ " li %1,0\n" \ - " li %1+1,0\n" \ + " li %L1,0\n" \ " b 3b\n" \ ".previous\n" \ EX_TABLE(1b, 4b) \ -- 2.51.0