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 DF9D51C4A00; Wed, 20 Nov 2024 14:08:36 +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=1732111717; cv=none; b=bJxKfrBrwGHniPxB5B4+gk6IEh6pGOkGB7lvcmDa8YJJZ5roCMQCvsCeHcAp2TOP2YAo4EVe35nEv7WCnvpXiwBIK8p/vKmPnQovP7dAgH4TP+KoAHDsUn1wmSCdRJQh+5zvbDyIKX4iM6a21vyPtJPEHA8wS1aN0EABMswtTwU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732111717; c=relaxed/simple; bh=4jdFJWsdI9PxVp1APJgllRrhtufNYUIdFGx8Y2yorsY=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=BPpOmSTguBJqOT0GinIRx6YZ/Lbdsuh/IrlemUTjWGykLEwQlv0dLLvGzmHFMDKoPD1dWmMR73C34jriT+LVBY8tBwQ0tBDQREW4DWHvnpAXfPqx4behro653Sju2ySHfAqccQ4VSgweSqbQYP6rX1rwnE93m+Vzk8VCkhVUoos= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=clasueZq; 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="clasueZq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0AEDEC4CECD; Wed, 20 Nov 2024 14:08:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1732111716; bh=4jdFJWsdI9PxVp1APJgllRrhtufNYUIdFGx8Y2yorsY=; h=From:To:Cc:Subject:Date:From; b=clasueZqwH9CiaOhsw4b39/1aSXEE0XSqJ8b97IVQliu+oXeLcubF8eE5z6YSwt3n pp61T7nDKIGs8smjHbwg3FsCWWk13+z2wWRhFPJXR5YW0oEm56JQeDplhauu92129Z NsDgLFIB4JxNbqPCl7a2HI8/K8Oy2Rt8eU17JcJBJmQnXUV7vaIiTpLSt3YL554fZB //+fxWTv3ldlbfFtgK/wewiEU87x4iBm2UAyPfb9y4gO3LcrOBkUdKZTe2F/CBdwCG Xx/36utxpzlJfyvwIdQNELwok70y11ilhg3A7vhzoVQxOWOFzckMX08LuAgfLCSCyG P5gnKuQ899ykg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Linus Walleij , kernel test robot , Nathan Chancellor , Russell King , Sasha Levin , linux@armlinux.org.uk, arnd@arndb.de, samitolvanen@google.com, linux-arm-kernel@lists.infradead.org, llvm@lists.linux.dev Subject: [PATCH AUTOSEL 5.4 1/2] ARM: 9434/1: cfi: Fix compilation corner case Date: Wed, 20 Nov 2024 09:08:28 -0500 Message-ID: <20241120140833.1769807-1-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.4.286 Content-Transfer-Encoding: 8bit From: Linus Walleij [ Upstream commit 4aea16b7cfb76bd3361858ceee6893ef5c9b5570 ] When enabling expert mode CONFIG_EXPERT and using that power user mode to disable the branch prediction hardening !CONFIG_HARDEN_BRANCH_PREDICTOR, the assembly linker in CLANG notices that some assembly in proc-v7.S does not have corresponding C call sites, i.e. the prototypes in proc-v7-bugs.c are enclosed in ifdef CONFIG_HARDEN_BRANCH_PREDICTOR so this assembly: SYM_TYPED_FUNC_START(cpu_v7_smc_switch_mm) SYM_TYPED_FUNC_START(cpu_v7_hvc_switch_mm) Results in: ld.lld: error: undefined symbol: __kcfi_typeid_cpu_v7_smc_switch_mm >>> referenced by proc-v7.S:94 (.../arch/arm/mm/proc-v7.S:94) >>> arch/arm/mm/proc-v7.o:(.text+0x108) in archive vmlinux.a ld.lld: error: undefined symbol: __kcfi_typeid_cpu_v7_hvc_switch_mm >>> referenced by proc-v7.S:105 (.../arch/arm/mm/proc-v7.S:105) >>> arch/arm/mm/proc-v7.o:(.text+0x124) in archive vmlinux.a Fix this by adding an additional requirement that CONFIG_HARDEN_BRANCH_PREDICTOR has to be enabled to compile these assembly calls. Closes: https://lore.kernel.org/oe-kbuild-all/202411041456.ZsoEiD7T-lkp@intel.com/ Reported-by: kernel test robot Reviewed-by: Nathan Chancellor Signed-off-by: Linus Walleij Signed-off-by: Russell King (Oracle) Signed-off-by: Sasha Levin --- arch/arm/mm/proc-v7.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index 48e0ef6f0dccf..aee85fd261f5d 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -91,7 +91,7 @@ ENTRY(cpu_v7_dcache_clean_area) ret lr ENDPROC(cpu_v7_dcache_clean_area) -#ifdef CONFIG_ARM_PSCI +#if defined(CONFIG_ARM_PSCI) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR) .arch_extension sec ENTRY(cpu_v7_smc_switch_mm) stmfd sp!, {r0 - r3} -- 2.43.0