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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id A8CEDC43217 for ; Thu, 24 Nov 2022 04:25:42 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0B5016B0072; Wed, 23 Nov 2022 23:25:42 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 03EA56B0074; Wed, 23 Nov 2022 23:25:41 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E21C66B0075; Wed, 23 Nov 2022 23:25:41 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id CBB4B6B0072 for ; Wed, 23 Nov 2022 23:25:41 -0500 (EST) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 78ACC40AD8 for ; Thu, 24 Nov 2022 04:25:41 +0000 (UTC) X-FDA: 80167047282.09.F5D33CC Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf27.hostedemail.com (Postfix) with ESMTP id 159714000D for ; Thu, 24 Nov 2022 04:25:39 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2756861F38; Thu, 24 Nov 2022 04:25:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 60DC5C433C1; Thu, 24 Nov 2022 04:25:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1669263938; bh=vOnl+PAW/vecWK18KoII+NqVjfMzySB3kHa1v947VSI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=f12NgdMoqauyCN2r9JRF0Ir96lgqOqdfJ7CMAfTzO+fTRgdOTXCfPeN32qIu+0POw bWUOzS5b0oHKt1lrqcF84EKQbrYA8bClwjGgAFpZVTTGzgKlXO8pXTU1Of9zYc5+Io WARqe5d/TFWiuX7HqxX2DfYExit7SNCneSzGJJhI= Date: Wed, 23 Nov 2022 20:25:37 -0800 From: Andrew Morton To: Jiasheng Jiang Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/vmalloc: Add check for KMEM_CACHE Message-Id: <20221123202537.3378bf960c01f9773f6a4675@linux-foundation.org> In-Reply-To: <20221124040226.17953-1-jiasheng@iscas.ac.cn> References: <20221124040226.17953-1-jiasheng@iscas.ac.cn> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=f12NgdMo; spf=pass (imf27.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1669263940; a=rsa-sha256; cv=none; b=h0x1cUD0IxzDRhS/UsxNFB5fGJ2XZoXzFLanYQfdm/8zv+9iBqLlB7WZR44woAb9cFBXlC S7LAqMRw5pyNoI8eF5FkY1XdPPYl8OiL+9WTm1bmMmgL3BDG53dzhHyB9tR5rKLVUKKJtb YaGtQYkgP3ZXqsDouFHqKONkNSo8Ueg= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1669263940; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=ZPXY+Il2iHbeOCONsaHDL0rxmOOGgxienNLy6p5TpaU=; b=Uv6Ppqeby04yfVKY38jFzsgm+5pDCXODDkyNge1jyhjqkBu2uMjb9NVrWB91uSGtgvn7Qd SZOffoBRjhCj9K234zMq3KJ7uw1QzyfZmP5ySljx7jTLwpcdr4dZ/VbvBYga0NODbn1311 RHBp2qM1+fG80WzUS/cUmMfWg36kTNA= X-Rspamd-Queue-Id: 159714000D X-Rspam-User: Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=f12NgdMo; spf=pass (imf27.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Rspamd-Server: rspam06 X-Stat-Signature: u6tw96dj57f6qib1rgji51i17qde4gtx X-HE-Tag: 1669263939-280258 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, 24 Nov 2022 12:02:26 +0800 Jiasheng Jiang wrote: > As KMEM_CACHE may return NULL pointer, it should > be better to check the return value in order to > avoid NULL pointer dereference in kmem_cache_zalloc. > > ... > > @@ -2426,15 +2426,17 @@ void __init vmalloc_init(void) Linux assumes that allocation attempts from __init code will succeed. Because if they fail so early in the boot process, the system is so utterly messed up that we may as well just go oops.