From nobody Thu Feb 12 04:51:36 2026 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 96100C77B60 for ; Fri, 28 Apr 2023 10:02:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345892AbjD1KB6 (ORCPT ); Fri, 28 Apr 2023 06:01:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43722 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345847AbjD1KBc (ORCPT ); Fri, 28 Apr 2023 06:01:32 -0400 Received: from out187-3.us.a.mail.aliyun.com (out187-3.us.a.mail.aliyun.com [47.90.187.3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9875944AB for ; Fri, 28 Apr 2023 03:01:06 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R201e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018047198;MF=houwenlong.hwl@antgroup.com;NM=1;PH=DS;RN=16;SR=0;TI=SMTPD_---.STDfsHv_1682675644; Received: from localhost(mailfrom:houwenlong.hwl@antgroup.com fp:SMTPD_---.STDfsHv_1682675644) by smtp.aliyun-inc.com; Fri, 28 Apr 2023 17:54:05 +0800 From: "Hou Wenlong" To: linux-kernel@vger.kernel.org Cc: "Thomas Garnier" , "Lai Jiangshan" , "Kees Cook" , "Hou Wenlong" , "Thomas Gleixner" , "Ingo Molnar" , "Borislav Petkov" , "Dave Hansen" , , "H. Peter Anvin" , "Juergen Gross" , "Anshuman Khandual" , "Mike Rapoport" , "Josh Poimboeuf" , "Pasha Tatashin" Subject: [PATCH RFC 40/43] x86/boot: Fill kernel image puds dynamically Date: Fri, 28 Apr 2023 17:51:20 +0800 Message-Id: X-Mailer: git-send-email 2.31.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" For PIE kernel, it could be randomized in any address. Later, kernel image would be moved down the top 2G, so fille kernel image puds dynamically. Signed-off-by: Hou Wenlong Cc: Thomas Garnier a Cc: Lai Jiangshan Cc: Kees Cook --- arch/x86/kernel/head64.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 8295b547b64f..c5cd61aab8ae 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -239,8 +239,18 @@ unsigned long __head __startup_64(unsigned long physad= dr, } =20 pud =3D fixup_pointer(&level3_kernel_pgt, physaddr); - pud[510] +=3D load_delta; - pud[511] +=3D load_delta; + if (IS_ENABLED(CONFIG_X86_PIE)) { + pud[510] =3D 0; + pud[511] =3D 0; + + i =3D pud_index(text_base); + pgtable_flags =3D _KERNPG_TABLE_NOENC - __START_KERNEL_map + load_delta; + pud[i] =3D pgtable_flags + SYM_ABS_VAL(level2_kernel_pgt); + pud[i + 1] =3D pgtable_flags + SYM_ABS_VAL(level2_fixmap_pgt); + } else { + pud[510] +=3D load_delta; + pud[511] +=3D load_delta; + } =20 pmd =3D fixup_pointer(level2_fixmap_pgt, physaddr); for (i =3D FIXMAP_PMD_TOP; i > FIXMAP_PMD_TOP - FIXMAP_PMD_NUM; i--) --=20 2.31.1