From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932525AbbLBPHU (ORCPT ); Wed, 2 Dec 2015 10:07:20 -0500 Received: from rs224.mailgun.us ([209.61.151.224]:43528 "EHLO rs224.mailgun.us" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932393AbbLBPHR (ORCPT ); Wed, 2 Dec 2015 10:07:17 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=variantweb.net; s=smtp; q=dns; h=Sender: From: To: Cc: Subject: Date: Message-Id: In-Reply-To: References; b=FBDFAiaXslscwacVK053jKrNZ7clxslG2qCPnpG5i+B+lkOBRxbmw7H+z7Pz/D2zqrP8jk x2Wyy0K5uqzzRKrSfAaQ778X+lckNshvDeNaKP32N8BKDdjMJ419nqJXjlxVv2+WuMZxdfWb MErCF6+nGQBxx66r8upEySmd+T3ZU= X-Mailgun-Sid: WyJmNDFlMyIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgIjlkYjc2Il0= From: Seth Jennings To: Greg Kroah-Hartman Cc: Seth Jennings , Andrew Banman , Andrew Morton , Russ Anderson , linux-kernel@vger.kernel.org Subject: [PATCH 3/3] drivers: memory: prohibit offlining of memory blocks with missing sections Date: Wed, 2 Dec 2015 09:07:01 -0600 Message-Id: <1449068821-9870-3-git-send-email-sjennings@variantweb.net> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1449068821-9870-1-git-send-email-sjennings@variantweb.net> References: <1449068821-9870-1-git-send-email-sjennings@variantweb.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org bdee237c and 982792c7 introduced large block sizes for x86. This made it possible to have multiple sections per memory block where previously, there was a only every one section per block. Since blocks consist of contiguous ranges of section, there can be holes in the blocks where sections are not present. If one attempts to offline such a block, a crash occurs since the code is not designed to deal with this. This patch is a quick fix to gaurd against the crash by not allowing blocks with non-present sections to be offlined. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=107781 Reported-by: Andrew Banman Signed-off-by: Seth Jennings --- drivers/base/memory.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/base/memory.c b/drivers/base/memory.c index dd30744..6d7b14c 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -303,6 +303,10 @@ static int memory_subsys_offline(struct device *dev) if (mem->state == MEM_OFFLINE) return 0; + /* Can't offline block with non-present sections */ + if (mem->section_count != sections_per_block) + return -EINVAL; + return memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE); } -- 2.5.0