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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E2044EB64DD for ; Sat, 24 Jun 2023 00:01:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232303AbjFXAB1 (ORCPT ); Fri, 23 Jun 2023 20:01:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60454 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232331AbjFXAAj (ORCPT ); Fri, 23 Jun 2023 20:00:39 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C1092941 for ; Fri, 23 Jun 2023 17:00:37 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 05800615DE for ; Sat, 24 Jun 2023 00:00:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 57829C433CB; Sat, 24 Jun 2023 00:00:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1687564836; bh=wqvMxWqdKG4hEddp0oWsdxs0QJUA3xP6nHpH3ghN2VI=; h=Date:To:From:Subject:From; b=y25yyuGnWa0xx0kyOnISV7+QHRN4RIFkO8qPG4KBs5b9cePzHoRfousvjKzCOfQfP yXqIHrr56Z4YWSII8MoIsnBm9O1v5wGeTrewNX20XTwoB+uKx2HZOQgYulb2r5koLt sZvEsO0U/TCIpekoRBtWPp87z0sZ1Y/64VbFRM+M= Date: Fri, 23 Jun 2023 17:00:35 -0700 To: mm-commits@vger.kernel.org, willy@infradead.org, vannapurve@google.com, songmuchun@bytedance.com, sidhartha.kumar@oracle.com, gregkh@linuxfoundation.org, erdemaktas@google.com, dan.carpenter@linaro.org, ackerleytng@google.com, mike.kravetz@oracle.com, akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] hugetlb-revert-use-of-page_cache_next_miss.patch removed from -mm tree Message-Id: <20230624000036.57829C433CB@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The quilt patch titled Subject: hugetlb: revert use of page_cache_next_miss() has been removed from the -mm tree. Its filename was hugetlb-revert-use-of-page_cache_next_miss.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Mike Kravetz Subject: hugetlb: revert use of page_cache_next_miss() Date: Wed, 21 Jun 2023 14:24:03 -0700 Ackerley Tng reported an issue with hugetlbfs fallocate as noted in the Closes tag. The issue showed up after the conversion of hugetlb page cache lookup code to use page_cache_next_miss. User visible effects are: - hugetlbfs fallocate incorrectly returns -EEXIST if pages are presnet in the file. - hugetlb pages will not be included in core dumps if they need to be brought in via GUP. - userfaultfd UFFDIO_COPY will not notice pages already present in the cache. It may try to allocate a new page and potentially return ENOMEM as opposed to EEXIST. Revert the use page_cache_next_miss() in hugetlb code. IMPORTANT NOTE FOR STABLE BACKPORTS: This patch will apply cleanly to v6.3. However, due to the change of filemap_get_folio() return values, it will not function correctly. This patch must be modified for stable backports. [dan.carpenter@linaro.org: fix hugetlbfs_pagecache_present()] Link: https://lkml.kernel.org/r/efa86091-6a2c-4064-8f55-9b44e1313015@moroto.mountain Link: https://lkml.kernel.org/r/20230621212403.174710-2-mike.kravetz@oracle.com Fixes: d0ce0e47b323 ("mm/hugetlb: convert hugetlb fault paths to use alloc_hugetlb_folio()") Signed-off-by: Mike Kravetz Signed-off-by: Dan Carpenter Reported-by: Ackerley Tng Closes: https://lore.kernel.org/linux-mm/cover.1683069252.git.ackerleytng@google.com Reviewed-by: Sidhartha Kumar Cc: Erdem Aktas Cc: Greg Kroah-Hartman Cc: Matthew Wilcox Cc: Muchun Song Cc: Vishal Annapurve Signed-off-by: Andrew Morton --- fs/hugetlbfs/inode.c | 8 +++----- mm/hugetlb.c | 12 ++++++------ 2 files changed, 9 insertions(+), 11 deletions(-) --- a/fs/hugetlbfs/inode.c~hugetlb-revert-use-of-page_cache_next_miss +++ a/fs/hugetlbfs/inode.c @@ -821,7 +821,6 @@ static long hugetlbfs_fallocate(struct f */ struct folio *folio; unsigned long addr; - bool present; cond_resched(); @@ -842,10 +841,9 @@ static long hugetlbfs_fallocate(struct f mutex_lock(&hugetlb_fault_mutex_table[hash]); /* See if already present in mapping to avoid alloc/free */ - rcu_read_lock(); - present = page_cache_next_miss(mapping, index, 1) != index; - rcu_read_unlock(); - if (present) { + folio = filemap_get_folio(mapping, index); + if (!IS_ERR(folio)) { + folio_put(folio); mutex_unlock(&hugetlb_fault_mutex_table[hash]); continue; } --- a/mm/hugetlb.c~hugetlb-revert-use-of-page_cache_next_miss +++ a/mm/hugetlb.c @@ -5728,13 +5728,13 @@ static bool hugetlbfs_pagecache_present( { struct address_space *mapping = vma->vm_file->f_mapping; pgoff_t idx = vma_hugecache_offset(h, vma, address); - bool present; + struct folio *folio; - rcu_read_lock(); - present = page_cache_next_miss(mapping, idx, 1) != idx; - rcu_read_unlock(); - - return present; + folio = filemap_get_folio(mapping, idx); + if (IS_ERR(folio)) + return false; + folio_put(folio); + return true; } int hugetlb_add_to_page_cache(struct folio *folio, struct address_space *mapping, _ Patches currently in -mm which might be from mike.kravetz@oracle.com are