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=-8.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 B2FEEC07542 for ; Mon, 27 May 2019 09:39:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8623821744 for ; Mon, 27 May 2019 09:39:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="WdyDohT7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726836AbfE0JjH (ORCPT ); Mon, 27 May 2019 05:39:07 -0400 Received: from mail-lf1-f65.google.com ([209.85.167.65]:34209 "EHLO mail-lf1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726743AbfE0Ji6 (ORCPT ); Mon, 27 May 2019 05:38:58 -0400 Received: by mail-lf1-f65.google.com with SMTP id v18so11588488lfi.1 for ; Mon, 27 May 2019 02:38:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=5tFxW9hH4KTKWLbD5PL7NocPZCk93KxY6ol7ln5ws1s=; b=WdyDohT79RWv5sQw8j/CoiyAF1ieXhBzh55F/UbajT9jF/0uJ67nJC3KNnHTUPoI0T oUBP1DChU3kD4+oixvGJZjalRgEuupfxfw3tAciwmhJ8azlHnw/9zdY211g0HetUZqHo pcLoUQjOziPwn7lefVncMQD2ZdI0BPz9lVodeDp4CHJnFXoNRL5DLmsx9CbYtKPcw5No UCR/uvKE8YK6JKhvoExYF/ggb0izBa8VIDKiBvqNTs5o+yZ8G4Hrb4BkQtKx1Z4I6Pvb 0wCCaGD8KZvWTFTFFm9Z0/PQLWWVEWN+7T6Eg+/RaX3QawT2c0YbBBzBtdNCU4JatZ7j wZ9A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=5tFxW9hH4KTKWLbD5PL7NocPZCk93KxY6ol7ln5ws1s=; b=FxOF8uRJY4Jo+XQarH46OWPfbIKCirISnWlBujp3NTUcsZBRNpSmsFBcGC8DzK2/sl 9ewUY7HUT7MqevTsMroW1TPWLIa0bWZ3NQeFkp+4ugYgKpYQguustsLZ+6YRocuFrWNw 8evxGwtSq+AJQNze/gnbZ8qTqorleUQ8+V3UU6ZUtpm4SAjpVbPYUrcrQgZAGkcfO7Sx RP9Jf7x1fEfl1FPmzTRmJt4sZtDur7aLDslWT7ZR/dbm0tUAqWPhgRaHSWHOa9Zu7l9R j4cbnha8+NK3EPHYOIIQjmkvstnBwt3CwKgGrJWPKW1bn3KiNu14G9xCOMyFd5OJI2N+ meCg== X-Gm-Message-State: APjAAAXMQh348CzYNFIyKfp5sWHeadW/I6MBbo+VhFBf+39XansGQeDO YzEDjFJsgHQ0Ys8v9eck34I= X-Google-Smtp-Source: APXvYqywlNbALD5TT5l11okB4ZaZ9LJNYUAYl35+RlPAv4hvj0NbaW0wQ0+uLocyyjJWapoGw3TE1w== X-Received: by 2002:ac2:5324:: with SMTP id f4mr5086344lfh.156.1558949936459; Mon, 27 May 2019 02:38:56 -0700 (PDT) Received: from pc636.semobile.internal ([37.139.158.167]) by smtp.gmail.com with ESMTPSA id z26sm2176293lfg.31.2019.05.27.02.38.55 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 27 May 2019 02:38:55 -0700 (PDT) From: "Uladzislau Rezki (Sony)" To: Andrew Morton , linux-mm@kvack.org Cc: Roman Gushchin , Uladzislau Rezki , Hillf Danton , Michal Hocko , Matthew Wilcox , LKML , Thomas Garnier , Oleksiy Avramchenko , Steven Rostedt , Joel Fernandes , Thomas Gleixner , Ingo Molnar , Tejun Heo Subject: [PATCH v3 4/4] mm/vmap: move BUG_ON() check to the unlink_va() Date: Mon, 27 May 2019 11:38:42 +0200 Message-Id: <20190527093842.10701-5-urezki@gmail.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190527093842.10701-1-urezki@gmail.com> References: <20190527093842.10701-1-urezki@gmail.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Move the BUG_ON()/RB_EMPTY_NODE() check under unlink_va() function, it means if an empty node gets freed it is a BUG thus is considered as faulty behaviour. Signed-off-by: Uladzislau Rezki (Sony) --- mm/vmalloc.c | 24 +++++++++--------------- 1 file changed, 9 insertions(+), 15 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 371aba9a4bf1..340959b81228 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -533,20 +533,16 @@ link_va(struct vmap_area *va, struct rb_root *root, static __always_inline void unlink_va(struct vmap_area *va, struct rb_root *root) { - /* - * During merging a VA node can be empty, therefore - * not linked with the tree nor list. Just check it. - */ - if (!RB_EMPTY_NODE(&va->rb_node)) { - if (root == &free_vmap_area_root) - rb_erase_augmented(&va->rb_node, - root, &free_vmap_area_rb_augment_cb); - else - rb_erase(&va->rb_node, root); + BUG_ON(RB_EMPTY_NODE(&va->rb_node)); - list_del(&va->list); - RB_CLEAR_NODE(&va->rb_node); - } + if (root == &free_vmap_area_root) + rb_erase_augmented(&va->rb_node, + root, &free_vmap_area_rb_augment_cb); + else + rb_erase(&va->rb_node, root); + + list_del(&va->list); + RB_CLEAR_NODE(&va->rb_node); } #if DEBUG_AUGMENT_PROPAGATE_CHECK @@ -1187,8 +1183,6 @@ EXPORT_SYMBOL_GPL(unregister_vmap_purge_notifier); static void __free_vmap_area(struct vmap_area *va) { - BUG_ON(RB_EMPTY_NODE(&va->rb_node)); - /* * Remove from the busy tree/list. */ -- 2.11.0