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=-13.0 required=3.0 tests=BAYES_00, 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 1AF59C433DF for ; Fri, 14 Aug 2020 15:20:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F06C620885 for ; Fri, 14 Aug 2020 15:20:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726971AbgHNPUK (ORCPT ); Fri, 14 Aug 2020 11:20:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45488 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726297AbgHNPUH (ORCPT ); Fri, 14 Aug 2020 11:20:07 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED0BDC061384 for ; Fri, 14 Aug 2020 08:20:06 -0700 (PDT) Received: from cap.home.8bytes.org (p4ff2bb8d.dip0.t-ipconnect.de [79.242.187.141]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 205C74BB; Fri, 14 Aug 2020 17:20:02 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Ingo Molnar , Mike Rapoport , Dave Hansen , Andy Lutomirski , Peter Zijlstra , hpa@zytor.com, Linus Torvalds , Jason@zx2c4.com, Andrew Morton , linux-kernel@vger.kernel.org, kirill.shutemov@intel.com, Joerg Roedel Subject: [PATCH 1/2] x86/mm/64: Do not sync vmalloc/ioremap mappings Date: Fri, 14 Aug 2020 17:19:46 +0200 Message-Id: <20200814151947.26229-2-joro@8bytes.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200814151947.26229-1-joro@8bytes.org> References: <20200814151947.26229-1-joro@8bytes.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Joerg Roedel Remove the code to sync the vmalloc and ioremap ranges for x86-64. The page-table pages are all pre-allocated so that synchronization is no longer necessary. This is a patch that already went into the kernel as: commit 8bb9bf242d1f ("x86/mm/64: Do not sync vmalloc/ioremap mappings") But it had to be reverted later because it unveiled a bug from: commit 6eb82f994026 ("x86/mm: Pre-allocate P4D/PUD pages for vmalloc area") The bug in that commit causes the P4D/PUD pages not to be correctly allocated, making the synchronization still necessary. That issue got fixed meanwhile upstream: commit 995909a4e22b ("x86/mm/64: Do not dereference non-present PGD entries") With that fix it is safe again to remove the page-table synchronization for vmalloc/ioremap ranges on x86-64. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/pgtable_64_types.h | 2 -- arch/x86/mm/init_64.c | 5 ----- 2 files changed, 7 deletions(-) diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h index 8f63efb2a2cc..52e5f5f2240d 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -159,6 +159,4 @@ extern unsigned int ptrs_per_p4d; #define PGD_KERNEL_START ((PAGE_SIZE / 2) / sizeof(pgd_t)) -#define ARCH_PAGE_TABLE_SYNC_MASK (pgtable_l5_enabled() ? PGTBL_PGD_MODIFIED : PGTBL_P4D_MODIFIED) - #endif /* _ASM_X86_PGTABLE_64_DEFS_H */ diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index a4ac13cc3fdc..777d83546764 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -217,11 +217,6 @@ static void sync_global_pgds(unsigned long start, unsigned long end) sync_global_pgds_l4(start, end); } -void arch_sync_kernel_mappings(unsigned long start, unsigned long end) -{ - sync_global_pgds(start, end); -} - /* * NOTE: This function is marked __ref because it calls __init function * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0. -- 2.28.0