From patchwork Sun Jun 27 21:53:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 467971 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS 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 21679C48BC2 for ; Sun, 27 Jun 2021 21:53:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0C69461A1D for ; Sun, 27 Jun 2021 21:53:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231810AbhF0V4O (ORCPT ); Sun, 27 Jun 2021 17:56:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:54958 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231694AbhF0V4O (ORCPT ); Sun, 27 Jun 2021 17:56:14 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id A6EDF61C31; Sun, 27 Jun 2021 21:53:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1624830830; bh=w8DPIgiNAdDNa4gTGOmTfO7RuCs+3w79+kjkVi9Tc7I=; h=Date:From:To:Subject:From; b=HPrMv5LloQIExGLBou7390TieDj0tvmBCYNlhTv5HzZmQkcu9vgcBO+PH1do6GRxR O7mROaDtK6GQb/LLNDOis3P4XCf3GaaHRKy7RhQHZI/hKknlHKGNxztlKaLxyPd/L/ 8Tyze6aLJLedPrCsUExzDQZbsFvKwjztpb9FR2rQ= Date: Sun, 27 Jun 2021 14:53:49 -0700 From: akpm@linux-foundation.org To: apopple@nvidia.com, hughd@google.com, kirill.shutemov@linux.intel.com, mm-commits@vger.kernel.org, peterx@redhat.com, rcampbell@nvidia.com, shy828301@gmail.com, stable@vger.kernel.org, wangyugui@e16-tech.com, will@kernel.org, willy@infradead.org, ziy@nvidia.com Subject: [merged] mm-thp-another-pvmw_sync-fix-in-page_vma_mapped_walk.patch removed from -mm tree Message-ID: <20210627215349.QjAsSy7ki%akpm@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch titled Subject: mm/thp: another PVMW_SYNC fix in page_vma_mapped_walk() has been removed from the -mm tree. Its filename was mm-thp-another-pvmw_sync-fix-in-page_vma_mapped_walk.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Hugh Dickins Subject: mm/thp: another PVMW_SYNC fix in page_vma_mapped_walk() Aha! Shouldn't that quick scan over pte_none()s make sure that it holds ptlock in the PVMW_SYNC case? That too might have been responsible for BUGs or WARNs in split_huge_page_to_list() or its unmap_page(), though I've never seen any. Link: https://lkml.kernel.org/r/1bdf384c-8137-a149-2a1e-475a4791c3c@google.com Link: https://lore.kernel.org/linux-mm/20210412180659.B9E3.409509F4@e16-tech.com/ Fixes: ace71a19cec5 ("mm: introduce page_vma_mapped_walk()") Signed-off-by: Hugh Dickins Acked-by: Kirill A. Shutemov Tested-by: Wang Yugui Cc: Alistair Popple Cc: Matthew Wilcox Cc: Peter Xu Cc: Ralph Campbell Cc: Will Deacon Cc: Yang Shi Cc: Zi Yan Cc: Signed-off-by: Andrew Morton --- mm/page_vma_mapped.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/mm/page_vma_mapped.c~mm-thp-another-pvmw_sync-fix-in-page_vma_mapped_walk +++ a/mm/page_vma_mapped.c @@ -276,6 +276,10 @@ next_pte: goto restart; } pvmw->pte++; + if ((pvmw->flags & PVMW_SYNC) && !pvmw->ptl) { + pvmw->ptl = pte_lockptr(mm, pvmw->pmd); + spin_lock(pvmw->ptl); + } } while (pte_none(*pvmw->pte)); if (!pvmw->ptl) {