From patchwork Wed Oct 21 20:44:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Kravetz X-Patchwork-Id: 290240 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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_GIT 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 51FDBC4363A for ; Wed, 21 Oct 2020 20:44:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D6D692415A for ; Wed, 21 Oct 2020 20:44:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="EYv7vOYM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2505298AbgJUUo6 (ORCPT ); Wed, 21 Oct 2020 16:44:58 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:60242 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2505026AbgJUUo5 (ORCPT ); Wed, 21 Oct 2020 16:44:57 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 09LKiCWd162250; Wed, 21 Oct 2020 20:44:44 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=corp-2020-01-29; bh=1b8YRCjA/uvkQdkZbUeVGHOgdFx9CEWFOQ/Jb+PIWWc=; b=EYv7vOYML6S00NFk6CmZRhtPZjcDRyjPbSE/XlfY4XUadiruIkhpj3opG4bAhexwH6BB kshbgx8yq6RGLixVHCBloBss3vB4QHBz7ChITvtcQn6lyRIiXOgiogA2MQgB3p+zhb4x FjNkEdZPbu0Fx3awiSWcQDQyjnFoTT5rb6ycleitsq0U8WAiRN2YtiWnpPsu9Pm5vF90 tET7OqHukLmH/PFuQlTOHW+hBvaoUtBxa/RIUc5KNWnaGawZWkOVWpdWk/Q2DccuItSk 8PkHql863X/Dlas7TTjEjmNOjKYxCmUUXtD5NxP6UnhenPQNrz+XkSUVh0qDXyrM7LKj pQ== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by userp2120.oracle.com with ESMTP id 34ak16k3dk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 21 Oct 2020 20:44:43 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 09LKZ0ik100071; Wed, 21 Oct 2020 20:44:43 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by userp3030.oracle.com with ESMTP id 348ahy1bh5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 21 Oct 2020 20:44:43 +0000 Received: from abhmp0004.oracle.com (abhmp0004.oracle.com [141.146.116.10]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 09LKiff1003552; Wed, 21 Oct 2020 20:44:41 GMT Received: from monkey.oracle.com (/50.38.35.18) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 21 Oct 2020 13:44:41 -0700 From: Mike Kravetz To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: David Hildenbrand , Mina Almasry , Michal Privoznik , "Michael S . Tsirkin" , Michal Hocko , Muchun Song , "Aneesh Kumar K . V" , Tejun Heo , Andrew Morton , Mike Kravetz , stable@vger.kernel.org Subject: [PATCH] hugetlb_cgroup: fix reservation accounting Date: Wed, 21 Oct 2020 13:44:26 -0700 Message-Id: <20201021204426.36069-1-mike.kravetz@oracle.com> X-Mailer: git-send-email 2.25.4 MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9781 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 phishscore=0 bulkscore=0 malwarescore=0 spamscore=0 mlxlogscore=999 mlxscore=0 suspectscore=2 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010210142 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9781 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 phishscore=0 priorityscore=1501 clxscore=1011 malwarescore=0 mlxscore=0 adultscore=0 lowpriorityscore=0 impostorscore=0 spamscore=0 mlxlogscore=999 suspectscore=2 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010210143 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Michal Privoznik was using "free page reporting" in QEMU/virtio-balloon with hugetlbfs and hit the warning below. QEMU with free page hinting uses fallocate(FALLOC_FL_PUNCH_HOLE) to discard pages that are reported as free by a VM. The reporting granularity is in pageblock granularity. So when the guest reports 2M chunks, we fallocate(FALLOC_FL_PUNCH_HOLE) one huge page in QEMU. [ 315.251417] ------------[ cut here ]------------ [ 315.251424] WARNING: CPU: 7 PID: 6636 at mm/page_counter.c:57 page_counter_uncharge+0x4b/0x50 [ 315.251425] Modules linked in: ... [ 315.251466] CPU: 7 PID: 6636 Comm: qemu-system-x86 Not tainted 5.9.0 #137 [ 315.251467] Hardware name: Gigabyte Technology Co., Ltd. X570 AORUS PRO/X570 AORUS PRO, BIOS F21 07/31/2020 [ 315.251469] RIP: 0010:page_counter_uncharge+0x4b/0x50 ... [ 315.251479] Call Trace: [ 315.251485] hugetlb_cgroup_uncharge_file_region+0x4b/0x80 [ 315.251487] region_del+0x1d3/0x300 [ 315.251489] hugetlb_unreserve_pages+0x39/0xb0 [ 315.251492] remove_inode_hugepages+0x1a8/0x3d0 [ 315.251495] ? tlb_finish_mmu+0x7a/0x1d0 [ 315.251497] hugetlbfs_fallocate+0x3c4/0x5c0 [ 315.251519] ? kvm_arch_vcpu_ioctl_run+0x614/0x1700 [kvm] [ 315.251522] ? file_has_perm+0xa2/0xb0 [ 315.251524] ? inode_security+0xc/0x60 [ 315.251525] ? selinux_file_permission+0x4e/0x120 [ 315.251527] vfs_fallocate+0x146/0x290 [ 315.251529] __x64_sys_fallocate+0x3e/0x70 [ 315.251531] do_syscall_64+0x33/0x40 [ 315.251533] entry_SYSCALL_64_after_hwframe+0x44/0xa9 ... [ 315.251542] ---[ end trace 4c88c62ccb1349c9 ]--- Investigation of the issue uncovered bugs in hugetlb cgroup reservation accounting. This patch addresses the found issues. Fixes: 075a61d07a8e ("hugetlb_cgroup: add accounting for shared mappings") Cc: Reported-by: Michal Privoznik Co-developed-by: David Hildenbrand Signed-off-by: David Hildenbrand Signed-off-by: Mike Kravetz Tested-by: Michal Privoznik Acked-by: Michael S. Tsirkin Reviewed-by: Mina Almasry --- mm/hugetlb.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 67fc6383995b..b853a11de14f 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -655,6 +655,8 @@ static long region_del(struct resv_map *resv, long f, long t) } del += t - f; + hugetlb_cgroup_uncharge_file_region( + resv, rg, t - f); /* New entry for end of split region */ nrg->from = t; @@ -667,9 +669,6 @@ static long region_del(struct resv_map *resv, long f, long t) /* Original entry is trimmed */ rg->to = f; - hugetlb_cgroup_uncharge_file_region( - resv, rg, nrg->to - nrg->from); - list_add(&nrg->link, &rg->link); nrg = NULL; break; @@ -685,17 +684,17 @@ static long region_del(struct resv_map *resv, long f, long t) } if (f <= rg->from) { /* Trim beginning of region */ - del += t - rg->from; - rg->from = t; - hugetlb_cgroup_uncharge_file_region(resv, rg, t - rg->from); - } else { /* Trim end of region */ - del += rg->to - f; - rg->to = f; + del += t - rg->from; + rg->from = t; + } else { /* Trim end of region */ hugetlb_cgroup_uncharge_file_region(resv, rg, rg->to - f); + + del += rg->to - f; + rg->to = f; } } @@ -2454,6 +2453,9 @@ struct page *alloc_huge_page(struct vm_area_struct *vma, rsv_adjust = hugepage_subpool_put_pages(spool, 1); hugetlb_acct_memory(h, -rsv_adjust); + if (deferred_reserve) + hugetlb_cgroup_uncharge_page_rsvd(hstate_index(h), + pages_per_huge_page(h), page); } return page;