From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753452AbdK1EE0 (ORCPT ); Mon, 27 Nov 2017 23:04:26 -0500 Received: from mail-pl0-f67.google.com ([209.85.160.67]:40378 "EHLO mail-pl0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751658AbdK1EEZ (ORCPT ); Mon, 27 Nov 2017 23:04:25 -0500 X-Google-Smtp-Source: AGs4zMaQFK/756Io29EYHhbWp5At6DynOwxwv/y/88BV8mlvyeTPpW/+a2fedjlyBfxgJ4BLF1+ASg== From: zhouzhouyi@gmail.com To: aryabinin@virtuozzo.com, glider@google.com, dvyukov@google.com, kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Zhouyi Zhou Subject: [PATCH 1/1] kasan: fix livelock in qlist_move_cache Date: Tue, 28 Nov 2017 04:04:02 +0000 Message-Id: <1511841842-3786-1-git-send-email-zhouzhouyi@gmail.com> X-Mailer: git-send-email 1.7.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Zhouyi Zhou This patch fix livelock by conditionally release cpu to let others has a chance to run. Tested on x86_64. Signed-off-by: Zhouyi Zhou --- mm/kasan/quarantine.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c index 3a8ddf8..33eeff4 100644 --- a/mm/kasan/quarantine.c +++ b/mm/kasan/quarantine.c @@ -265,10 +265,13 @@ static void qlist_move_cache(struct qlist_head *from, struct kmem_cache *cache) { struct qlist_node *curr; + struct qlist_head tmp_head; + unsigned long flags; if (unlikely(qlist_empty(from))) return; + qlist_init(&tmp_head); curr = from->head; qlist_init(from); while (curr) { @@ -278,10 +281,17 @@ static void qlist_move_cache(struct qlist_head *from, if (obj_cache == cache) qlist_put(to, curr, obj_cache->size); else - qlist_put(from, curr, obj_cache->size); + qlist_put(&tmp_head, curr, obj_cache->size); curr = next; + + if (need_resched()) { + spin_unlock_irqrestore(&quarantine_lock, flags); + cond_resched(); + spin_lock_irqsave(&quarantine_lock, flags); + } } + qlist_move_all(&tmp_head, from); } static void per_cpu_remove_cache(void *arg) -- 2.1.4