From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f199.google.com (mail-wr0-f199.google.com [209.85.128.199]) by kanga.kvack.org (Postfix) with ESMTP id C8A426B0261 for ; Thu, 30 Nov 2017 17:15:25 -0500 (EST) Received: by mail-wr0-f199.google.com with SMTP id a45so4713209wra.14 for ; Thu, 30 Nov 2017 14:15:25 -0800 (PST) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id x14si3999183wrg.146.2017.11.30.14.15.24 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 30 Nov 2017 14:15:24 -0800 (PST) Date: Thu, 30 Nov 2017 14:15:22 -0800 From: akpm@linux-foundation.org Subject: [patch 04/15] mm/mempolicy: add nodes_empty check in SYSC_migrate_pages Message-ID: <5a2082fa.bXLNoQ4bvY4J0ImP%akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, akpm@linux-foundation.org, xieyisheng1@huawei.com, ak@linux.intel.com, cl@linux.com, mingo@kernel.org, n-horiguchi@ah.jp.nec.com, rientjes@google.com, salls@cs.ucsb.edu, tanxiaojun@huawei.com, vbabka@suse.cz From: Yisheng Xie Subject: mm/mempolicy: add nodes_empty check in SYSC_migrate_pages As in manpage of migrate_pages, the errno should be set to EINVAL when none of the node IDs specified by new_nodes are on-line and allowed by the process's current cpuset context, or none of the specified nodes contain memory. However, when test by following case: new_nodes = 0; old_nodes = 0xf; ret = migrate_pages(pid, old_nodes, new_nodes, MAX); The ret will be 0 and no errno is set. As the new_nodes is empty, we should expect EINVAL as documented. To fix the case like above, this patch check whether target nodes AND current task_nodes is empty, and then check whether AND node_states[N_MEMORY] is empty. Link: http://lkml.kernel.org/r/1510882624-44342-4-git-send-email-xieyisheng1@huawei.com Signed-off-by: Yisheng Xie Cc: Andi Kleen Cc: Chris Salls Cc: Christopher Lameter Cc: David Rientjes Cc: Ingo Molnar Cc: Naoya Horiguchi Cc: Tan Xiaojun Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- mm/mempolicy.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff -puN mm/mempolicy.c~mm-mempolicy-add-nodes_empty-check-in-sysc_migrate_pages mm/mempolicy.c --- a/mm/mempolicy.c~mm-mempolicy-add-nodes_empty-check-in-sysc_migrate_pages +++ a/mm/mempolicy.c @@ -1433,10 +1433,14 @@ SYSCALL_DEFINE4(migrate_pages, pid_t, pi goto out_put; } - if (!nodes_subset(*new, node_states[N_MEMORY])) { - err = -EINVAL; + task_nodes = cpuset_mems_allowed(current); + nodes_and(*new, *new, task_nodes); + if (nodes_empty(*new)) + goto out_put; + + nodes_and(*new, *new, node_states[N_MEMORY]); + if (nodes_empty(*new)) goto out_put; - } err = security_task_movememory(task); if (err) _ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org