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 99CFFC6379F for ; Mon, 13 Feb 2023 14:58:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231131AbjBMO6M (ORCPT ); Mon, 13 Feb 2023 09:58:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54752 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231133AbjBMO6D (ORCPT ); Mon, 13 Feb 2023 09:58:03 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6AAE11C7FA for ; Mon, 13 Feb 2023 06:57:26 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id C2A9CB8125F for ; Mon, 13 Feb 2023 14:57:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E947AC433D2; Mon, 13 Feb 2023 14:57:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1676300243; bh=Z2Bzz69Yq77/4sUTL4JztDuef8lhfC0FwsuSg/n13jw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UCu9wHbg5E+xdc2w0ypLhECSnxgC83mcjIHPwbTwZfJgf2U3lmhpLAOuVc4k9k92M bH01Wp2qzpLnK4cUzx2Mz6lLIhWGUrrUoOm/QT40cKCXX+Ch74FfUQ7IS7tTOconjW vVchRTo70++9LYAFXi4wP3vOwDg/hCyjWRtWOS+8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Miaohe Lin , Huang Ying , Alistair Popple , Christoph Hellwig , Christoph Lameter , David Hildenbrand , David Howells , Mike Kravetz , Muchun Song , Oscar Salvador , Peter Xu , Andrew Morton , Sasha Levin , kernel test robot Subject: [PATCH 5.15 04/67] mm/migration: return errno when isolate_huge_page failed Date: Mon, 13 Feb 2023 15:48:45 +0100 Message-Id: <20230213144732.533780756@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230213144732.336342050@linuxfoundation.org> References: <20230213144732.336342050@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Miaohe Lin [ Upstream commit 7ce82f4c3f3ead13a9d9498768e3b1a79975c4d8 ] We might fail to isolate huge page due to e.g. the page is under migration which cleared HPageMigratable. We should return errno in this case rather than always return 1 which could confuse the user, i.e. the caller might think all of the memory is migrated while the hugetlb page is left behind. We make the prototype of isolate_huge_page consistent with isolate_lru_page as suggested by Huang Ying and rename isolate_huge_page to isolate_hugetlb as suggested by Muchun to improve the readability. Link: https://lkml.kernel.org/r/20220530113016.16663-4-linmiaohe@huawei.com Fixes: e8db67eb0ded ("mm: migrate: move_pages() supports thp migration") Signed-off-by: Miaohe Lin Suggested-by: Huang Ying Reported-by: kernel test robot (build error) Cc: Alistair Popple Cc: Christoph Hellwig Cc: Christoph Lameter Cc: David Hildenbrand Cc: David Howells Cc: Mike Kravetz Cc: Muchun Song Cc: Oscar Salvador Cc: Peter Xu Signed-off-by: Andrew Morton Stable-dep-of: 73bdf65ea748 ("migrate: hugetlb: check for hugetlb shared PMD in node migration") Signed-off-by: Sasha Levin --- include/linux/hugetlb.h | 6 +++--- mm/gup.c | 2 +- mm/hugetlb.c | 11 +++++------ mm/memory-failure.c | 2 +- mm/memory_hotplug.c | 2 +- mm/mempolicy.c | 2 +- mm/migrate.c | 7 ++++--- 7 files changed, 16 insertions(+), 16 deletions(-) diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index cac25ad9d643f..f98d747f983b9 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -166,7 +166,7 @@ bool hugetlb_reserve_pages(struct inode *inode, long from, long to, vm_flags_t vm_flags); long hugetlb_unreserve_pages(struct inode *inode, long start, long end, long freed); -bool isolate_huge_page(struct page *page, struct list_head *list); +int isolate_hugetlb(struct page *page, struct list_head *list); int get_hwpoison_huge_page(struct page *page, bool *hugetlb); int get_huge_page_for_hwpoison(unsigned long pfn, int flags); void putback_active_hugepage(struct page *page); @@ -354,9 +354,9 @@ static inline pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr, return NULL; } -static inline bool isolate_huge_page(struct page *page, struct list_head *list) +static inline int isolate_hugetlb(struct page *page, struct list_head *list) { - return false; + return -EBUSY; } static inline int get_hwpoison_huge_page(struct page *page, bool *hugetlb) diff --git a/mm/gup.c b/mm/gup.c index 2370565a81dc3..0a1839b325747 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1877,7 +1877,7 @@ static long check_and_migrate_movable_pages(unsigned long nr_pages, */ if (!is_pinnable_page(head)) { if (PageHuge(head)) { - if (!isolate_huge_page(head, &movable_page_list)) + if (isolate_hugetlb(head, &movable_page_list)) isolation_error_count++; } else { if (!PageLRU(head) && drain_allow) { diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 8599f16d4aa4f..2f5c1b2456ef2 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2656,8 +2656,7 @@ static int alloc_and_dissolve_huge_page(struct hstate *h, struct page *old_page, * Fail with -EBUSY if not possible. */ spin_unlock_irq(&hugetlb_lock); - if (!isolate_huge_page(old_page, list)) - ret = -EBUSY; + ret = isolate_hugetlb(old_page, list); spin_lock_irq(&hugetlb_lock); goto free_new; } else if (!HPageFreed(old_page)) { @@ -2733,7 +2732,7 @@ int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list) if (hstate_is_gigantic(h)) return -ENOMEM; - if (page_count(head) && isolate_huge_page(head, list)) + if (page_count(head) && !isolate_hugetlb(head, list)) ret = 0; else if (!page_count(head)) ret = alloc_and_dissolve_huge_page(h, head, list); @@ -6277,15 +6276,15 @@ follow_huge_pgd(struct mm_struct *mm, unsigned long address, pgd_t *pgd, int fla return pte_page(*(pte_t *)pgd) + ((address & ~PGDIR_MASK) >> PAGE_SHIFT); } -bool isolate_huge_page(struct page *page, struct list_head *list) +int isolate_hugetlb(struct page *page, struct list_head *list) { - bool ret = true; + int ret = 0; spin_lock_irq(&hugetlb_lock); if (!PageHeadHuge(page) || !HPageMigratable(page) || !get_page_unless_zero(page)) { - ret = false; + ret = -EBUSY; goto unlock; } ClearHPageMigratable(page); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 2ad0f45800916..9f9dd968fbe3c 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -2106,7 +2106,7 @@ static bool isolate_page(struct page *page, struct list_head *pagelist) bool lru = PageLRU(page); if (PageHuge(page)) { - isolated = isolate_huge_page(page, pagelist); + isolated = !isolate_hugetlb(page, pagelist); } else { if (lru) isolated = !isolate_lru_page(page); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 9fd0be32a281e..81f2a97c886c9 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1704,7 +1704,7 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) if (PageHuge(page)) { pfn = page_to_pfn(head) + compound_nr(head) - 1; - isolate_huge_page(head, &source); + isolate_hugetlb(head, &source); continue; } else if (PageTransHuge(page)) pfn = page_to_pfn(head) + thp_nr_pages(page) - 1; diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 4472be6f123db..8687781b41c96 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -604,7 +604,7 @@ static int queue_pages_hugetlb(pte_t *pte, unsigned long hmask, /* With MPOL_MF_MOVE, we migrate only unshared hugepage. */ if (flags & (MPOL_MF_MOVE_ALL) || (flags & MPOL_MF_MOVE && page_mapcount(page) == 1)) { - if (!isolate_huge_page(page, qp->pagelist) && + if (isolate_hugetlb(page, qp->pagelist) && (flags & MPOL_MF_STRICT)) /* * Failed to isolate page but allow migrating pages diff --git a/mm/migrate.c b/mm/migrate.c index 7da052c6cf1ea..dd50b1cc089e0 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -134,7 +134,7 @@ static void putback_movable_page(struct page *page) * * This function shall be used whenever the isolated pageset has been * built from lru, balloon, hugetlbfs page. See isolate_migratepages_range() - * and isolate_huge_page(). + * and isolate_hugetlb(). */ void putback_movable_pages(struct list_head *l) { @@ -1722,8 +1722,9 @@ static int add_page_for_migration(struct mm_struct *mm, unsigned long addr, if (PageHuge(page)) { if (PageHead(page)) { - isolate_huge_page(page, pagelist); - err = 1; + err = isolate_hugetlb(page, pagelist); + if (!err) + err = 1; } } else { struct page *head; -- 2.39.0