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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 76111C433EF for ; Thu, 14 Oct 2021 03:35:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5971C61040 for ; Thu, 14 Oct 2021 03:35:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230156AbhJNDhe (ORCPT ); Wed, 13 Oct 2021 23:37:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60364 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230126AbhJNDhc (ORCPT ); Wed, 13 Oct 2021 23:37:32 -0400 Received: from mail-pl1-x62e.google.com (mail-pl1-x62e.google.com [IPv6:2607:f8b0:4864:20::62e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A2F2C061570 for ; Wed, 13 Oct 2021 20:35:28 -0700 (PDT) Received: by mail-pl1-x62e.google.com with SMTP id c4so3209406pls.6 for ; Wed, 13 Oct 2021 20:35:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=3kMfdZR7u3SGVAlrTiFoKn2/xZAEuhY7vC7t+axQgCY=; b=GP2gzClAzGvfiXU2UzYKiEiiXF9MJ9TkMyCBj8Cy43ALhy5k12HBIUVfvecGvULyJl yxo/x09Pwt4JlRhIATFvHll8Yr3yisMEXf0LQg/D1bG2bTsaCQRaNY1TpvdnD0npfxoE NrruwbAcLj9S+lzojp8d/vl4Nu/vOCDq7VshUBlTey6wN24qHJcWEAWqNpXQq16j4Nir 93ORpRjUhA/Qdz85rkKDjjM9VdK0uC57PZtYeXN0PjemLZbpe4YmTSFIDzdXLtpARXTY oGuf6QnVQGYr2664LV1qZI/8Xt3L3jRaNp4z1ajN7vfFLtVTOh45c5UbOwUaQ7SPU6rn kR0w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=3kMfdZR7u3SGVAlrTiFoKn2/xZAEuhY7vC7t+axQgCY=; b=fQjMC3nMtvf9k8U8plt3l6A2jHGUFxMEjAODX+1qdLGXKHHwpejtgM6fYuFCduWb/E 4zhwmtY21W1dg5spU2ZUP3vNLd4RqxVgB0O3bhn74CAQpD0iegJNfpbTOgmouZOrpNiK X7Cy0RpdknWm7KubTLa7D/GwmcXs/BD2/QQn7RWoi6SC+b+xnSZI5dmnSPQJKEh6Pxad bx73sdFBQ00OS3DahJwO369MMtMMtWPJqhPrE3Gdxec73Mhbvz+w8jETWO9jsvsjN/bI cH+AxXZGq0BwCYj+kTQHslUMxofj/NrQWREhEJNaIJYtq/A+tDm4R/iRwLWyBDLazMoV evKg== X-Gm-Message-State: AOAM533eob8wON0fSxPKJt8Ei26wm1itkCpQTZF9H+Tn0/oFW+cwschX +9Fk+YsFkUVfHCwUSLtfAN1vQr+CmXo= X-Google-Smtp-Source: ABdhPJyfD+Dkpb93e42pxX6KwY19qy2zop++om+LtHLG5IPzPblYdhXUYAUJKYUCcaz3mzasLSRNjw== X-Received: by 2002:a17:90a:9d81:: with SMTP id k1mr18148717pjp.153.1634182527889; Wed, 13 Oct 2021 20:35:27 -0700 (PDT) Received: from localhost ([198.11.178.15]) by smtp.gmail.com with ESMTPSA id rj2sm882535pjb.32.2021.10.13.20.35.27 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 13 Oct 2021 20:35:27 -0700 (PDT) From: Lai Jiangshan To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, Lai Jiangshan , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" Subject: [PATCH V3 15/49] x86/entry: Add C verion of SWITCH_TO_KERNEL_CR3 as switch_to_kernel_cr3() Date: Thu, 14 Oct 2021 11:33:38 +0800 Message-Id: <20211014033414.16321-10-jiangshanlai@gmail.com> X-Mailer: git-send-email 2.19.1.6.gb485710b In-Reply-To: <20211014031413.14471-1-jiangshanlai@gmail.com> References: <20211014031413.14471-1-jiangshanlai@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lai Jiangshan The C version switch_to_kernel_cr3() implements SWITCH_TO_KERNEL_CR3(). No functional difference intended. Signed-off-by: Lai Jiangshan --- arch/x86/entry/entry64.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/arch/x86/entry/entry64.c b/arch/x86/entry/entry64.c index 9813a30dbadb..9a5c535b1ddf 100644 --- a/arch/x86/entry/entry64.c +++ b/arch/x86/entry/entry64.c @@ -14,3 +14,27 @@ #include extern unsigned char asm_load_gs_index_gs_change[]; + +#ifdef CONFIG_PAGE_TABLE_ISOLATION +static __always_inline void pti_switch_to_kernel_cr3(unsigned long user_cr3) +{ + /* + * Clear PCID and "PAGE_TABLE_ISOLATION bit", point CR3 + * at kernel pagetables: + */ + unsigned long cr3 = user_cr3 & ~PTI_USER_PGTABLE_AND_PCID_MASK; + + if (static_cpu_has(X86_FEATURE_PCID)) + cr3 |= X86_CR3_PCID_NOFLUSH; + + native_write_cr3(cr3); +} + +static __always_inline void switch_to_kernel_cr3(void) +{ + if (static_cpu_has(X86_FEATURE_PTI)) + pti_switch_to_kernel_cr3(__native_read_cr3()); +} +#else +static __always_inline void switch_to_kernel_cr3(void) {} +#endif -- 2.19.1.6.gb485710b