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 C065CEB64DC for ; Mon, 19 Jun 2023 20:20:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229810AbjFSUUW (ORCPT ); Mon, 19 Jun 2023 16:20:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33454 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229875AbjFSUUN (ORCPT ); Mon, 19 Jun 2023 16:20:13 -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 1B32FE63; Mon, 19 Jun 2023 13:20:12 -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 82AF060EB7; Mon, 19 Jun 2023 20:20:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D3C77C433C8; Mon, 19 Jun 2023 20:20:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1687206010; bh=10/kCI5Ttrf4hRsSJqVVVucNRiK6mVo1zX3xiVZfAto=; h=Date:To:From:Subject:From; b=qZXSbITGvw+QYzXwnV4uOVk8vvrmuErjDHt46uFAiuXTuIqlcUh0BcWTaJDYT2uyi FdrOtqpxSwhqnG4d4kNZqBqonKrbTy+zv2miF3zDeyESEQ7H4QVPtVFkV1SuVjdzl8 1KmL75bLZgCL/TcR1oIgrNlPG6jSg7RSfwHd034g= Date: Mon, 19 Jun 2023 13:20:10 -0700 To: mm-commits@vger.kernel.org, vivek.kasireddy@intel.com, stable@vger.kernel.org, muchun.song@linux.dev, mhocko@suse.com, kraxel@redhat.com, kirill.shutemov@linux.intel.com, junxiao.chang@intel.com, jthoughton@google.com, jmarchan@redhat.com, gregkh@linuxfoundation.org, dongwon.kim@intel.com, david@redhat.com, mike.kravetz@oracle.com, akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-hotfixes-stable] udmabuf-revert-add-support-for-mapping-hugepages-v4.patch removed from -mm tree Message-Id: <20230619202010.D3C77C433C8@smtp.kernel.org> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The quilt patch titled Subject: udmabuf: revert 'Add support for mapping hugepages (v4)' has been removed from the -mm tree. Its filename was udmabuf-revert-add-support-for-mapping-hugepages-v4.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Mike Kravetz Subject: udmabuf: revert 'Add support for mapping hugepages (v4)' Date: Thu, 8 Jun 2023 13:49:27 -0700 This effectively reverts commit 16c243e99d33 ("udmabuf: Add support for mapping hugepages (v4)"). Recently, Junxiao Chang found a BUG with page map counting as described here [1]. This issue pointed out that the udmabuf driver was making direct use of subpages of hugetlb pages. This is not a good idea, and no other mm code attempts such use. In addition to the mapcount issue, this also causes issues with hugetlb vmemmap optimization and page poisoning. For now, remove hugetlb support. If udmabuf wants to be used on hugetlb mappings, it should be changed to only use complete hugetlb pages. This will require different alignment and size requirements on the UDMABUF_CREATE API. [1] https://lore.kernel.org/linux-mm/20230512072036.1027784-1-junxiao.chang@intel.com/ Link: https://lkml.kernel.org/r/20230608204927.88711-1-mike.kravetz@oracle.com Fixes: 16c243e99d33 ("udmabuf: Add support for mapping hugepages (v4)") Signed-off-by: Mike Kravetz Acked-by: Greg Kroah-Hartman Acked-by: Vivek Kasireddy Acked-by: Gerd Hoffmann Cc: David Hildenbrand Cc: Dongwon Kim Cc: James Houghton Cc: Jerome Marchand Cc: Junxiao Chang Cc: Kirill A. Shutemov Cc: Michal Hocko Cc: Muchun Song Cc: Signed-off-by: Andrew Morton --- drivers/dma-buf/udmabuf.c | 47 ++++-------------------------------- 1 file changed, 6 insertions(+), 41 deletions(-) --- a/drivers/dma-buf/udmabuf.c~udmabuf-revert-add-support-for-mapping-hugepages-v4 +++ a/drivers/dma-buf/udmabuf.c @@ -12,7 +12,6 @@ #include #include #include -#include #include #include @@ -207,9 +206,7 @@ static long udmabuf_create(struct miscde struct udmabuf *ubuf; struct dma_buf *buf; pgoff_t pgoff, pgcnt, pgidx, pgbuf = 0, pglimit; - struct page *page, *hpage = NULL; - pgoff_t subpgoff, maxsubpgs; - struct hstate *hpstate; + struct page *page; int seals, ret = -EINVAL; u32 i, flags; @@ -245,7 +242,7 @@ static long udmabuf_create(struct miscde if (!memfd) goto err; mapping = memfd->f_mapping; - if (!shmem_mapping(mapping) && !is_file_hugepages(memfd)) + if (!shmem_mapping(mapping)) goto err; seals = memfd_fcntl(memfd, F_GET_SEALS, 0); if (seals == -EINVAL) @@ -256,48 +253,16 @@ static long udmabuf_create(struct miscde goto err; pgoff = list[i].offset >> PAGE_SHIFT; pgcnt = list[i].size >> PAGE_SHIFT; - if (is_file_hugepages(memfd)) { - hpstate = hstate_file(memfd); - pgoff = list[i].offset >> huge_page_shift(hpstate); - subpgoff = (list[i].offset & - ~huge_page_mask(hpstate)) >> PAGE_SHIFT; - maxsubpgs = huge_page_size(hpstate) >> PAGE_SHIFT; - } for (pgidx = 0; pgidx < pgcnt; pgidx++) { - if (is_file_hugepages(memfd)) { - if (!hpage) { - hpage = find_get_page_flags(mapping, pgoff, - FGP_ACCESSED); - if (!hpage) { - ret = -EINVAL; - goto err; - } - } - page = hpage + subpgoff; - get_page(page); - subpgoff++; - if (subpgoff == maxsubpgs) { - put_page(hpage); - hpage = NULL; - subpgoff = 0; - pgoff++; - } - } else { - page = shmem_read_mapping_page(mapping, - pgoff + pgidx); - if (IS_ERR(page)) { - ret = PTR_ERR(page); - goto err; - } + page = shmem_read_mapping_page(mapping, pgoff + pgidx); + if (IS_ERR(page)) { + ret = PTR_ERR(page); + goto err; } ubuf->pages[pgbuf++] = page; } fput(memfd); memfd = NULL; - if (hpage) { - put_page(hpage); - hpage = NULL; - } } exp_info.ops = &udmabuf_ops; _ Patches currently in -mm which might be from mike.kravetz@oracle.com are