From patchwork Sun Jul 28 13:06:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Colin Ian King X-Patchwork-Id: 1137971 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=canonical.com Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 45xNNx2T69z9sBF; Sun, 28 Jul 2019 23:06:09 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1hrisF-0002pC-Gn; Sun, 28 Jul 2019 13:06:03 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.86_2) (envelope-from ) id 1hrisD-0002p4-HS for kernel-team@lists.ubuntu.com; Sun, 28 Jul 2019 13:06:01 +0000 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1hrisD-000632-58; Sun, 28 Jul 2019 13:06:01 +0000 From: Colin King To: kernel-team@lists.ubuntu.com Subject: [PATCH][SRU][HWE BIONIC][DISCO][V2] x86/mm: Sync also unmappings in vmalloc_sync_all() Date: Sun, 28 Jul 2019 14:06:00 +0100 Message-Id: <20190728130600.10637-1-colin.king@canonical.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" From: Colin Ian King BugLink: https://bugs.launchpad.net/bugs/1838115 With huge-page ioremap areas the unmappings also need to be synced between all page-tables. Otherwise it can cause data corruption when a region is unmapped and later re-used. Make the vmalloc_sync_one() function ready to sync unmappings and make sure vmalloc_sync_all() iterates over all page-tables even when an unmapped PMD is found. Fixes: 5d72b4fba40ef ('x86, mm: support huge I/O mapping capability I/F') Signed-off-by: Joerg Roedel Signed-off-by: Thomas Gleixner Reviewed-by: Dave Hansen Link: https://lkml.kernel.org/r/20190719184652.11391-3-joro@8bytes.org (backported from commit 8e998fc24de47c55b47a887f6c95ab91acd4a720) Signed-off-by: Colin Ian King Acked-by: Stefan Bader --- arch/x86/mm/fault.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 9d5c75f..eb246b3 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -193,11 +193,12 @@ static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address) pmd = pmd_offset(pud, address); pmd_k = pmd_offset(pud_k, address); - if (!pmd_present(*pmd_k)) - return NULL; - if (!pmd_present(*pmd)) + if (pmd_present(*pmd) != pmd_present(*pmd_k)) set_pmd(pmd, *pmd_k); + + if (!pmd_present(*pmd_k)) + return NULL; else BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k)); @@ -219,17 +220,13 @@ void vmalloc_sync_all(void) spin_lock(&pgd_lock); list_for_each_entry(page, &pgd_list, lru) { spinlock_t *pgt_lock; - pmd_t *ret; /* the pgt_lock only for Xen */ pgt_lock = &pgd_page_get_mm(page)->page_table_lock; spin_lock(pgt_lock); - ret = vmalloc_sync_one(page_address(page), address); + vmalloc_sync_one(page_address(page), address); spin_unlock(pgt_lock); - - if (!ret) - break; } spin_unlock(&pgd_lock); }