From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35807C31E40 for ; Fri, 9 Aug 2019 13:46:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 08474217F4 for ; Fri, 9 Aug 2019 13:46:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565358367; bh=KNH5LTo6U6LPt5LDid7xgLtnO528JweYiwo3EJ02Dd0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=O8U3pUY5Ezcd2POyPYvaFrgcIERtqj1bdQebjOvFlWzj/vwO67WtPU2zi1RdCXtx7 jThR23mXg3yrlFfTRKpUrdbMtIXxoVYiDEYnxcR4a1crJ8JtgSd3zG034eZpFRMX5B 83FdDYvHyY5i8xa9Hh+xxof46vQPATBMlv7/X1VQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406883AbfHINqG (ORCPT ); Fri, 9 Aug 2019 09:46:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:35564 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2406518AbfHINqE (ORCPT ); Fri, 9 Aug 2019 09:46:04 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2161D2171F; Fri, 9 Aug 2019 13:46:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565358363; bh=KNH5LTo6U6LPt5LDid7xgLtnO528JweYiwo3EJ02Dd0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Imetlo+7vokpctZdr/p6MJk0OIQN3p7m9TBcZLY6mrS2NRegJa2PYt+G2Y29hvhHj iSsWV0isF20eCkvfgpWkAdpo6BuY7pe3YZ2oFUrt20J1LHv88h71C4wF/CEs71T6p7 7Vhe2CdI5XN0do1RSc58igHB5O/nv4dlvlUfxvQg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Suzuki K Poulose , Mark Rutland , Will Deacon , Catalin Marinas , Sasha Levin Subject: [PATCH 4.4 02/21] arm64: cpufeature: Fix feature comparison for CTR_EL0.{CWG,ERG} Date: Fri, 9 Aug 2019 15:45:06 +0200 Message-Id: <20190809134241.664708388@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190809134241.565496442@linuxfoundation.org> References: <20190809134241.565496442@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org commit 147b9635e6347104b91f48ca9dca61eb0fbf2a54 upstream. If CTR_EL0.{CWG,ERG} are 0b0000 then they must be interpreted to have their architecturally maximum values, which defeats the use of FTR_HIGHER_SAFE when sanitising CPU ID registers on heterogeneous machines. Introduce FTR_HIGHER_OR_ZERO_SAFE so that these fields effectively saturate at zero. Fixes: 3c739b571084 ("arm64: Keep track of CPU feature registers") Cc: # 4.4.y only Reviewed-by: Suzuki K Poulose Acked-by: Mark Rutland Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin --- arch/arm64/include/asm/cpufeature.h | 7 ++++--- arch/arm64/kernel/cpufeature.c | 8 ++++++-- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index ad83c245781c3..0a66f8241f185 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -41,9 +41,10 @@ /* CPU feature register tracking */ enum ftr_type { - FTR_EXACT, /* Use a predefined safe value */ - FTR_LOWER_SAFE, /* Smaller value is safe */ - FTR_HIGHER_SAFE,/* Bigger value is safe */ + FTR_EXACT, /* Use a predefined safe value */ + FTR_LOWER_SAFE, /* Smaller value is safe */ + FTR_HIGHER_SAFE, /* Bigger value is safe */ + FTR_HIGHER_OR_ZERO_SAFE, /* Bigger value is safe, but 0 is biggest */ }; #define FTR_STRICT true /* SANITY check strict matching required */ diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index fff0bf2f889e1..062484d344509 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -130,8 +130,8 @@ static struct arm64_ftr_bits ftr_ctr[] = { ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 30, 1, 0), U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 29, 1, 1), /* DIC */ U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 28, 1, 1), /* IDC */ - U_ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_SAFE, 24, 4, 0), /* CWG */ - U_ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_SAFE, 20, 4, 0), /* ERG */ + U_ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, 24, 4, 0), /* CWG */ + U_ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, 20, 4, 0), /* ERG */ U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 1), /* DminLine */ /* * Linux can handle differing I-cache policies. Userspace JITs will @@ -341,6 +341,10 @@ static s64 arm64_ftr_safe_value(struct arm64_ftr_bits *ftrp, s64 new, s64 cur) case FTR_LOWER_SAFE: ret = new < cur ? new : cur; break; + case FTR_HIGHER_OR_ZERO_SAFE: + if (!cur || !new) + break; + /* Fallthrough */ case FTR_HIGHER_SAFE: ret = new > cur ? new : cur; break; -- 2.20.1