From patchwork Tue Apr 23 04:55:48 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Song Liu X-Patchwork-Id: 13639335 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 584EB1CAB3; Tue, 23 Apr 2024 04:55:54 +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=1713848154; cv=none; b=YAI7VeOIskTlQoJr0dkE4SIkHRzT/gq/nosGvkjBBR0V8etm3he1i1R2LVs9QQOUbiDsZ+mgCNWqJD50NkP42lOvPKwTv9vFeyKKTT4Bu83qhpmtzysxEGqTI8xx9jMZ6vuZiYMI4yVJ1CeEb0VlUT1UnlFrRjKIaCCb6MZVINA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713848154; c=relaxed/simple; bh=puryQ1J6mzWbCrUfIOEYUOuYeQHliVuNmWN99eIePwQ=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=b109HJHGIDbifzIPlkC5K8UgwXKspwDf2Rw0SNNNALaGHu8JVcP6dtsHuw9n03HOMYxAtBkFP1oMbxdMpVq2FoU0ukZaGsdmZSBCoz8dKhh2mcRM7/2DlOgnNgwgqdkU5KHnLKrpP54tUV6UqWE5tCMElC0tieIpzifTGQMK3dI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=le/Pv/qX; 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="le/Pv/qX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6F34BC116B1; Tue, 23 Apr 2024 04:55:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1713848153; bh=puryQ1J6mzWbCrUfIOEYUOuYeQHliVuNmWN99eIePwQ=; h=From:To:Cc:Subject:Date:From; b=le/Pv/qXNH6cmU/bEapqQld8Xy6qptw1W4yy3w76kNBPQoyRaCQ0eDU8aW4OhYWvQ 5Mw11o+v7XwagPHZlhU0O3PzlDxaSNWLya2r6tfJ2eLh6f061eRrKx2Aax9CCNIi40 9btXUZVsTznHsEP/H1yEccKQOxUkoFa5bdqrxukAQowOZhhLU7AzfKPatKfViNJz8F YlPKOkmW98paCxbsin3DxJ2//NPjoEEvFPmVbXH0uiYwYiMJb0X4DKvMA+EqLHRt7z uXd8GQaU2PNSFL2wkl7+gq+reYJfXzAQ0Hi/4hMHQK4jllydhVPYg3fUcJ0p+39rmQ BWvJQ5CtWZjFA== From: Song Liu To: linux-kernel@vger.kernel.org, bpf@vger.kernel.org, netdev@vger.kernel.org Cc: kernel-team@meta.com, Song Liu , stable@vger.kernel.org, Sean Christopherson , Ingo Molnar , Daniel Sneddon , Jakub Kicinski Subject: [PATCH] arch/Kconfig: Move SPECULATION_MITIGATIONS to arch/Kconfig Date: Mon, 22 Apr 2024 21:55:48 -0700 Message-ID: <20240423045548.1324969-1-song@kernel.org> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 SPECULATION_MITIGATIONS is currently defined only for x86. As a result, IS_ENABLED(CONFIG_SPECULATION_MITIGATIONS) is always false for other archs. f337a6a21e2f effectively set "mitigations=off" by default on non-x86 archs, which is not desired behavior. Jakub observed this change when running bpf selftests on s390 and arm64. Fix this by moving SPECULATION_MITIGATIONS to arch/Kconfig so that it is available in all archs and thus can be used safely in kernel/cpu.c Fixes: f337a6a21e2f ("x86/cpu: Actually turn off mitigations by default for SPECULATION_MITIGATIONS=n") Cc: stable@vger.kernel.org Cc: Sean Christopherson Cc: Ingo Molnar Cc: Daniel Sneddon Cc: Jakub Kicinski Signed-off-by: Song Liu --- arch/Kconfig | 10 ++++++++++ arch/x86/Kconfig | 10 ---------- 2 files changed, 10 insertions(+), 10 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index 9f066785bb71..8f4af75005f8 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -1609,4 +1609,14 @@ config CC_HAS_SANE_FUNCTION_ALIGNMENT # strict alignment always, even with -falign-functions. def_bool CC_HAS_MIN_FUNCTION_ALIGNMENT || CC_IS_CLANG +menuconfig SPECULATION_MITIGATIONS + bool "Mitigations for speculative execution vulnerabilities" + default y + help + Say Y here to enable options which enable mitigations for + speculative execution hardware vulnerabilities. + + If you say N, all mitigations will be disabled. You really + should know what you are doing to say so. + endmenu diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 39886bab943a..50c890fce5e0 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2486,16 +2486,6 @@ config PREFIX_SYMBOLS def_bool y depends on CALL_PADDING && !CFI_CLANG -menuconfig SPECULATION_MITIGATIONS - bool "Mitigations for speculative execution vulnerabilities" - default y - help - Say Y here to enable options which enable mitigations for - speculative execution hardware vulnerabilities. - - If you say N, all mitigations will be disabled. You really - should know what you are doing to say so. - if SPECULATION_MITIGATIONS config MITIGATION_PAGE_TABLE_ISOLATION