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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0B4D6C61DB3 for ; Thu, 12 Jan 2023 22:02:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234248AbjALWCt (ORCPT ); Thu, 12 Jan 2023 17:02:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55574 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233365AbjALWCN (ORCPT ); Thu, 12 Jan 2023 17:02:13 -0500 Received: from mail-pl1-x636.google.com (mail-pl1-x636.google.com [IPv6:2607:f8b0:4864:20::636]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 78477718B3 for ; Thu, 12 Jan 2023 13:51:31 -0800 (PST) Received: by mail-pl1-x636.google.com with SMTP id 17so21592833pll.0 for ; Thu, 12 Jan 2023 13:51:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=CWezmmHa6oj6qJtMomh+1hZZGWqGQrSyq0C7qN1MANE=; b=NrhE8GeB0gPtUpLJmL0nObCWCBwo04pER0QWC7YeN486f0tyfa3g3S7BtDUHlIbXFW zwrs+/K+DcCOmOq9CHZZri2ktplzmFfjR3ymQ4DGsJ6K3GoZmmlnw6aXM90nHdEUvKT6 K3lDHI2HhmuViAyN/43XcHXcUD0CiNOTpAm0o= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=CWezmmHa6oj6qJtMomh+1hZZGWqGQrSyq0C7qN1MANE=; b=2WiqqpeEdvK94SjV/+OeZ7KqO8fi767jKWVflFqzfXS5XRRzlMr6xlwDmNRcTQiN0m pIh2YlBs+muoE7/O5ALmMwD6nGAIPQ42HotT4g3YXCbOzPopVScuzej8+h3dXiHnAIyF xQ0EnQVdGawUc9nAcvzGUGnH6HAsOtYqDgmI8lFPFjyHfVPuN3RkQ/4sCM0fyjZ9MZBa HnbeOZlkk/pQxzHMkHF//FmLdX1myC3f+9HXQCO1+5pZ0SLAjl1MVJJAVjxxsFLKs0/W gAs7B0hd0vyYcHHpv/Mz+8JOviZZvX6y9Ti1nMQhMGu2g2sASUrDl/bTKWBfxV6R4EpX L7jA== X-Gm-Message-State: AFqh2kpwGRuYcFe4p9E/ZZ/twOHgBYrljtJWv+7f439cKtiBqj8I0SeD 7DJc5hFnWZ83cisUBc3CfS+l3w== X-Google-Smtp-Source: AMrXdXvH368zgSN+CqWpi3idJyL7uyuYLfW6YfP3XhLcEJ233wBi4Eh2ch09l2nZrresK14l3RKZWQ== X-Received: by 2002:a17:902:ba82:b0:189:86f0:70a2 with SMTP id k2-20020a170902ba8200b0018986f070a2mr37242231pls.43.1673560277885; Thu, 12 Jan 2023 13:51:17 -0800 (PST) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id im22-20020a170902bb1600b0018bc4493005sm12607234plb.269.2023.01.12.13.51.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 Jan 2023 13:51:17 -0800 (PST) Date: Thu, 12 Jan 2023 13:51:16 -0800 From: Kees Cook To: Peter Zijlstra Cc: x86@kernel.org, Joan Bruguera , linux-kernel@vger.kernel.org, Juergen Gross , "Rafael J. Wysocki" , xen-devel , Jan Beulich , Roger Pau Monne , mark.rutland@arm.com Subject: Re: [RFC][PATCH 2/6] x86/power: Inline write_cr[04]() Message-ID: <202301121351.B0CE02B@keescook> References: <20230112143141.645645775@infradead.org> <20230112143825.644480983@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230112143825.644480983@infradead.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 12, 2023 at 03:31:43PM +0100, Peter Zijlstra wrote: > Since we can't do CALL/RET until GS is restored and CR[04] pinning is > of dubious value in this code path, simply write the stored values. > > Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Kees Cook -- Kees Cook