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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 DF9FFC433DF for ; Wed, 12 Aug 2020 01:30:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BC5012080C for ; Wed, 12 Aug 2020 01:30:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597195834; bh=sQXGZRR5FxDM/6k3qfIGp/MrdAoAt7nXh7Py9Ecp2zc=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=fJySeQX58c/VT6YsXEOv7ZAkHSUk2izxtl8JAhSGUu4wDUWwq0viURLowmsL5t4Lh cAVJT7feF1VM/81SenNTPrjdMa7L2Ib7/ctw3dfxdgN+cM2xmBhrLS+7XWoheWd7zu 1Vcd6qYclmIhxdHS3/vaXowMyFmTX1WUyBVlll7M= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726422AbgHLBae (ORCPT ); Tue, 11 Aug 2020 21:30:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:57426 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726235AbgHLBae (ORCPT ); Tue, 11 Aug 2020 21:30:34 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5087E206B2; Wed, 12 Aug 2020 01:30:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597195833; bh=sQXGZRR5FxDM/6k3qfIGp/MrdAoAt7nXh7Py9Ecp2zc=; h=Date:From:To:Subject:In-Reply-To:From; b=PuEA7EApzS3lXFTIn5Wz+PmHeI8Cyn4A0vCDM7MivYr1GiadE+EDeURuepUlNFjEW aUNPpH0m+NQP8ARYBoJZKZN6j1mNWrbbJJu+enF0Bzd2R88NhaEluz1pycilPzquGm URyOx8hx0cjLhLUM07j1BnAhDQPquqNge6+7NuRI= Date: Tue, 11 Aug 2020 18:30:32 -0700 From: Andrew Morton To: akpm@linux-foundation.org, bhe@redhat.com, guojianchao@bytedance.com, linux-mm@kvack.org, mgorman@suse.de, mhocko@kernel.org, mike.kravetz@oracle.com, mm-commits@vger.kernel.org, rientjes@google.com, songmuchun@bytedance.com, torvalds@linux-foundation.org, walken@google.com Subject: [patch 006/165] mm/hugetlb: add mempolicy check in the reservation routine Message-ID: <20200812013032.yKTDCXQ06%akpm@linux-foundation.org> In-Reply-To: <20200811182949.e12ae9a472e3b5e27e16ad6c@linux-foundation.org> User-Agent: s-nail v14.8.16 Sender: mm-commits-owner@vger.kernel.org Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Muchun Song Subject: mm/hugetlb: add mempolicy check in the reservation routine In the reservation routine, we only check whether the cpuset meets the memory allocation requirements. But we ignore the mempolicy of MPOL_BIND case. If someone mmap hugetlb succeeds, but the subsequent memory allocation may fail due to mempolicy restrictions and receives the SIGBUS signal. This can be reproduced by the follow steps. 1) Compile the test case. cd tools/testing/selftests/vm/ gcc map_hugetlb.c -o map_hugetlb 2) Pre-allocate huge pages. Suppose there are 2 numa nodes in the system. Each node will pre-allocate one huge page. echo 2 > /proc/sys/vm/nr_hugepages 3) Run test case(mmap 4MB). We receive the SIGBUS signal. numactl --membind=3D0 ./map_hugetlb 4 With this patch applied, the mmap will fail in the step 3) and throw "mmap: Cannot allocate memory". [akpm@linux-foundation.org: include sched.h for `current'] Link: http://lkml.kernel.org/r/20200728034938.14993-1-songmuchun@bytedance.com Signed-off-by: Muchun Song Reported-by: Jianchao Guo Suggested-by: Michal Hocko Reviewed-by: Mike Kravetz Cc: David Rientjes Cc: Mel Gorman Cc: Michel Lespinasse Cc: Baoquan He Signed-off-by: Andrew Morton --- include/linux/mempolicy.h | 16 +++++++++++++++- mm/hugetlb.c | 24 +++++++++++++++++++----- mm/mempolicy.c | 2 +- 3 files changed, 35 insertions(+), 7 deletions(-) --- a/include/linux/mempolicy.h~mm-hugetlb-add-mempolicy-check-in-the-reservation-routine +++ a/include/linux/mempolicy.h @@ -6,7 +6,7 @@ #ifndef _LINUX_MEMPOLICY_H #define _LINUX_MEMPOLICY_H 1 - +#include #include #include #include @@ -152,6 +152,15 @@ extern int huge_node(struct vm_area_stru extern bool init_nodemask_of_mempolicy(nodemask_t *mask); extern bool mempolicy_nodemask_intersects(struct task_struct *tsk, const nodemask_t *mask); +extern nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy); + +static inline nodemask_t *policy_nodemask_current(gfp_t gfp) +{ + struct mempolicy *mpol = get_task_policy(current); + + return policy_nodemask(gfp, mpol); +} + extern unsigned int mempolicy_slab_node(void); extern enum zone_type policy_zone; @@ -281,5 +290,10 @@ static inline int mpol_misplaced(struct static inline void mpol_put_task_policy(struct task_struct *task) { } + +static inline nodemask_t *policy_nodemask_current(gfp_t gfp) +{ + return NULL; +} #endif /* CONFIG_NUMA */ #endif --- a/mm/hugetlb.c~mm-hugetlb-add-mempolicy-check-in-the-reservation-routine +++ a/mm/hugetlb.c @@ -3458,13 +3458,21 @@ static int __init default_hugepagesz_set } __setup("default_hugepagesz=", default_hugepagesz_setup); -static unsigned int cpuset_mems_nr(unsigned int *array) +static unsigned int allowed_mems_nr(struct hstate *h) { int node; unsigned int nr = 0; - - for_each_node_mask(node, cpuset_current_mems_allowed) - nr += array[node]; + nodemask_t *mpol_allowed; + unsigned int *array = h->free_huge_pages_node; + gfp_t gfp_mask = htlb_alloc_mask(h); + + mpol_allowed = policy_nodemask_current(gfp_mask); + + for_each_node_mask(node, cpuset_current_mems_allowed) { + if (!mpol_allowed || + (mpol_allowed && node_isset(node, *mpol_allowed))) + nr += array[node]; + } return nr; } @@ -3643,12 +3651,18 @@ static int hugetlb_acct_memory(struct hs * we fall back to check against current free page availability as * a best attempt and hopefully to minimize the impact of changing * semantics that cpuset has. + * + * Apart from cpuset, we also have memory policy mechanism that + * also determines from which node the kernel will allocate memory + * in a NUMA system. So similar to cpuset, we also should consider + * the memory policy of the current task. Similar to the description + * above. */ if (delta > 0) { if (gather_surplus_pages(h, delta) < 0) goto out; - if (delta > cpuset_mems_nr(h->free_huge_pages_node)) { + if (delta > allowed_mems_nr(h)) { return_unused_surplus_pages(h, delta); goto out; } --- a/mm/mempolicy.c~mm-hugetlb-add-mempolicy-check-in-the-reservation-routine +++ a/mm/mempolicy.c @@ -1890,7 +1890,7 @@ static int apply_policy_zone(struct memp * Return a nodemask representing a mempolicy for filtering nodes for * page allocation */ -static nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy) +nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy) { /* Lower zones don't get a nodemask applied for MPOL_BIND */ if (unlikely(policy->mode == MPOL_BIND) && _