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 2B92BC43334 for ; Mon, 4 Jul 2022 01:40:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229667AbiGDBkY (ORCPT ); Sun, 3 Jul 2022 21:40:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56664 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229461AbiGDBkX (ORCPT ); Sun, 3 Jul 2022 21:40:23 -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 7166E62D1 for ; Sun, 3 Jul 2022 18:40:21 -0700 (PDT) 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 dfw.source.kernel.org (Postfix) with ESMTPS id 0B324612D8 for ; Mon, 4 Jul 2022 01:40:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 555ABC341C6; Mon, 4 Jul 2022 01:40:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1656898820; bh=740tbWMbTe6wzqk8otYbz0Q1a3J7CyyMOBedJhcrGLw=; h=Date:To:From:Subject:From; b=D/vtcZPvi/DbiB95S9hTA5PSlbrGvF/oB7xaOYr+ErAC3H6GoK34X+oMLWAZwzCRb AXzAHYLbuwiLRe/Dfd9nLOtgR/wDs28aljiRWzaqCBYUmQRoqCuwIq0vPZpfIwQrtT 2X1hJ73+BL15meyT+b69XEbVPZV+q7TN2tfU6rm8= Date: Sun, 03 Jul 2022 18:40:19 -0700 To: mm-commits@vger.kernel.org, songmuchun@bytedance.com, shy828301@gmail.com, osalvador@suse.de, mike.kravetz@oracle.com, liushixin2@huawei.com, linmiaohe@huawei.com, david@redhat.com, naoya.horiguchi@nec.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-hugetlb-check-gigantic_page_runtime_supported-in-return_unused_surplus_pages.patch added to mm-unstable branch Message-Id: <20220704014020.555ABC341C6@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm/hugetlb: check gigantic_page_runtime_supported() in return_unused_surplus_pages() has been added to the -mm mm-unstable branch. Its filename is mm-hugetlb-check-gigantic_page_runtime_supported-in-return_unused_surplus_pages.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-hugetlb-check-gigantic_page_runtime_supported-in-return_unused_surplus_pages.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Naoya Horiguchi Subject: mm/hugetlb: check gigantic_page_runtime_supported() in return_unused_surplus_pages() Date: Mon, 4 Jul 2022 10:33:04 +0900 Patch series "mm, hwpoison: enable 1GB hugepage support", v4. This patch (of 9): I found a weird state of 1GB hugepage pool, caused by the following procedure: - run a process reserving all free 1GB hugepages, - shrink free 1GB hugepage pool to zero (i.e. writing 0 to /sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages), then - kill the reserving process. , then all the hugepages are free *and* surplus at the same time. $ cat /sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages 3 $ cat /sys/kernel/mm/hugepages/hugepages-1048576kB/free_hugepages 3 $ cat /sys/kernel/mm/hugepages/hugepages-1048576kB/resv_hugepages 0 $ cat /sys/kernel/mm/hugepages/hugepages-1048576kB/surplus_hugepages 3 This state is resolved by reserving and allocating the pages then freeing them again, so this seems not to result in serious problem. But it's a little surprising (shrinking pool suddenly fails). This behavior is caused by hstate_is_gigantic() check in return_unused_surplus_pages(). This was introduced so long ago in 2008 by commit aa888a74977a ("hugetlb: support larger than MAX_ORDER"), and at that time the gigantic pages were not supposed to be allocated/freed at run-time. Now kernel can support runtime allocation/free, so let's check gigantic_page_runtime_supported() together. Link: https://lkml.kernel.org/r/20220704013312.2415700-1-naoya.horiguchi@linux.dev Link: https://lkml.kernel.org/r/20220704013312.2415700-2-naoya.horiguchi@linux.dev Signed-off-by: Naoya Horiguchi Cc: David Hildenbrand Cc: Mike Kravetz Cc: Miaohe Lin Cc: Liu Shixin Cc: Yang Shi Cc: Oscar Salvador Cc: Muchun Song Signed-off-by: Andrew Morton --- mm/hugetlb.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) --- a/mm/hugetlb.c~mm-hugetlb-check-gigantic_page_runtime_supported-in-return_unused_surplus_pages +++ a/mm/hugetlb.c @@ -2432,8 +2432,7 @@ static void return_unused_surplus_pages( /* Uncommit the reservation */ h->resv_huge_pages -= unused_resv_pages; - /* Cannot return gigantic pages currently */ - if (hstate_is_gigantic(h)) + if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) goto out; /* @@ -3313,7 +3312,8 @@ static int set_max_huge_pages(struct hst * the user tries to allocate gigantic pages but let the user free the * boottime allocated gigantic pages. */ - if (hstate_is_gigantic(h) && !IS_ENABLED(CONFIG_CONTIG_ALLOC)) { + if (hstate_is_gigantic(h) && (!IS_ENABLED(CONFIG_CONTIG_ALLOC) || + !gigantic_page_runtime_supported())) { if (count > persistent_huge_pages(h)) { spin_unlock_irq(&hugetlb_lock); mutex_unlock(&h->resize_lock); @@ -3362,6 +3362,19 @@ static int set_max_huge_pages(struct hst } /* + * We can not decrease gigantic pool size if runtime modification + * is not supported. + */ + if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) { + if (count < persistent_huge_pages(h)) { + spin_unlock_irq(&hugetlb_lock); + mutex_unlock(&h->resize_lock); + NODEMASK_FREE(node_alloc_noretry); + return -EINVAL; + } + } + + /* * Decrease the pool size * First return free pages to the buddy allocator (being careful * to keep enough around to satisfy reservations). Then place _ Patches currently in -mm which might be from naoya.horiguchi@nec.com are mm-hugetlb-check-gigantic_page_runtime_supported-in-return_unused_surplus_pages.patch mm-hugetlb-separate-path-for-hwpoison-entry-in-copy_hugetlb_page_range.patch mm-hugetlb-make-pud_huge-and-follow_huge_pud-aware-of-non-present-pud-entry.patch mm-hwpoison-hugetlb-support-saving-mechanism-of-raw-error-pages.patch mm-hwpoison-make-unpoison-aware-of-raw-error-info-in-hwpoisoned-hugepage.patch mm-hwpoison-set-pg_hwpoison-for-busy-hugetlb-pages.patch mm-hwpoison-make-__page_handle_poison-returns-int.patch mm-hwpoison-skip-raw-hwpoison-page-in-freeing-1gb-hugepage.patch mm-hwpoison-enable-memory-error-handling-on-1gb-hugepage.patch