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=-6.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 50965C32788 for ; Thu, 11 Oct 2018 15:39:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1853B2087A for ; Thu, 11 Oct 2018 15:39:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="VDFngBzm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1853B2087A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729787AbeJKXGo (ORCPT ); Thu, 11 Oct 2018 19:06:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:35920 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726721AbeJKXGn (ORCPT ); Thu, 11 Oct 2018 19:06:43 -0400 Received: from localhost (ip-213-127-77-176.ip.prioritytelecom.net [213.127.77.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9393E2087A; Thu, 11 Oct 2018 15:38:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539272340; bh=5PM8j9KID4Uzwl0H9+BnEvyDcd5aqJ0WIdg5S5bx5Fg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VDFngBzmmUV+0SxeykoyneZq7hDZhT23dP4ULIaCF8ENYIlKw5U9WOY0LAIESE1Z4 EwNieJNLrmDkG+nMHZTLGFVTSbEO/OEu6zIFWwTg+R3DesKNIsImEN32w0o/q5ALHj EaV1dpmE0SesDfyZF92sbIBWCs/Uhf/rDQcuBrhA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiao Ni , Neil Brown , Shaohua Li , Sasha Levin Subject: [PATCH 3.18 075/120] RAID10 BUG_ON in raise_barrier when force is true and conf->barrier is 0 Date: Thu, 11 Oct 2018 17:34:16 +0200 Message-Id: <20181011152552.905621547@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181011152549.500488630@linuxfoundation.org> References: <20181011152549.500488630@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xiao Ni [ Upstream commit 1d0ffd264204eba1861865560f1f7f7a92919384 ] In raid10 reshape_request it gets max_sectors in read_balance. If the underlayer disks have bad blocks, the max_sectors is less than last. It will call goto read_more many times. It calls raise_barrier(conf, sectors_done != 0) every time. In this condition sectors_done is not 0. So the value passed to the argument force of raise_barrier is true. In raise_barrier it checks conf->barrier when force is true. If force is true and conf->barrier is 0, it panic. In this case reshape_request submits bio to under layer disks. And in the callback function of the bio it calls lower_barrier. If the bio finishes before calling raise_barrier again, it can trigger the BUG_ON. Add one pair of raise_barrier/lower_barrier to fix this bug. Signed-off-by: Xiao Ni Suggested-by: Neil Brown Signed-off-by: Shaohua Li Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid10.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -4423,11 +4423,12 @@ static sector_t reshape_request(struct m allow_barrier(conf); } + raise_barrier(conf, 0); read_more: /* Now schedule reads for blocks from sector_nr to last */ r10_bio = mempool_alloc(conf->r10buf_pool, GFP_NOIO); r10_bio->state = 0; - raise_barrier(conf, sectors_done != 0); + raise_barrier(conf, 1); atomic_set(&r10_bio->remaining, 0); r10_bio->mddev = mddev; r10_bio->sector = sector_nr; @@ -4532,6 +4533,8 @@ bio_full: if (sector_nr <= last) goto read_more; + lower_barrier(conf); + /* Now that we have done the whole section we can * update reshape_progress */