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=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,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 61C33C0044C for ; Wed, 31 Oct 2018 23:40:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1C29C20664 for ; Wed, 31 Oct 2018 23:40:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="rzfHSl1t" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1C29C20664 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.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 S1729884AbeKAIkt (ORCPT ); Thu, 1 Nov 2018 04:40:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:57034 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728094AbeKAIIS (ORCPT ); Thu, 1 Nov 2018 04:08:18 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7F47320821; Wed, 31 Oct 2018 23:08:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541027287; bh=I9mmCSxQK3HiHkChjF353pIwUH3sr3IYdDQnPZ4mui4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rzfHSl1tWbBh9AaTvY3EZMOZVGtCzXrapzsqO1wRn3u00YLk3i6yfUD3LHcMjmbnO lP0b0fMUOPG/+1GD+KULsVJRGSh2Q2dQa5SnCnLtRxNuRYZDBxgHTN1sSmVLHKOL0n vLJidIijmewcV5J8Pb5EAlRAiJ+Dt7wxK/r592wo= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Jia-Ju Bai , =?UTF-8?q?Matias=20Bj=C3=B8rling?= , Jens Axboe , Sasha Levin Subject: [PATCH AUTOSEL 4.18 013/126] lightnvm: pblk: fix two sleep-in-atomic-context bugs Date: Wed, 31 Oct 2018 19:06:01 -0400 Message-Id: <20181031230754.29029-13-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181031230754.29029-1-sashal@kernel.org> References: <20181031230754.29029-1-sashal@kernel.org> 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 From: Jia-Ju Bai [ Upstream commit 7325b4bbe5952e3e939f15de812f2ee0c0d33ca9 ] The driver may sleep with holding a spinlock. The function call paths (from bottom to top) in Linux-4.16 are: [FUNC] nvm_dev_dma_alloc(GFP_KERNEL) drivers/lightnvm/pblk-core.c, 754: nvm_dev_dma_alloc in pblk_line_submit_smeta_io drivers/lightnvm/pblk-core.c, 1048: pblk_line_submit_smeta_io in pblk_line_init_bb drivers/lightnvm/pblk-core.c, 1434: pblk_line_init_bb in pblk_line_replace_data drivers/lightnvm/pblk-recovery.c, 980: pblk_line_replace_data in pblk_recov_l2p drivers/lightnvm/pblk-recovery.c, 976: spin_lock in pblk_recov_l2p [FUNC] bio_map_kern(GFP_KERNEL) drivers/lightnvm/pblk-core.c, 762: bio_map_kern in pblk_line_submit_smeta_io drivers/lightnvm/pblk-core.c, 1048: pblk_line_submit_smeta_io in pblk_line_init_bb drivers/lightnvm/pblk-core.c, 1434: pblk_line_init_bb in pblk_line_replace_data drivers/lightnvm/pblk-recovery.c, 980: pblk_line_replace_data in pblk_recov_l2p drivers/lightnvm/pblk-recovery.c, 976: spin_lock in pblk_recov_l2p To fix these bugs, the call to pblk_line_replace_data() is moved out of the spinlock protection. These bugs are found by my static analysis tool DSAC. Signed-off-by: Jia-Ju Bai Reviewed-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- drivers/lightnvm/pblk-recovery.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/lightnvm/pblk-recovery.c b/drivers/lightnvm/pblk-recovery.c index d83466b3821b..958bda8a69b7 100644 --- a/drivers/lightnvm/pblk-recovery.c +++ b/drivers/lightnvm/pblk-recovery.c @@ -956,12 +956,14 @@ struct pblk_line *pblk_recov_l2p(struct pblk *pblk) } } - spin_lock(&l_mg->free_lock); if (!open_lines) { + spin_lock(&l_mg->free_lock); WARN_ON_ONCE(!test_and_clear_bit(meta_line, &l_mg->meta_bitmap)); + spin_unlock(&l_mg->free_lock); pblk_line_replace_data(pblk); } else { + spin_lock(&l_mg->free_lock); /* Allocate next line for preparation */ l_mg->data_next = pblk_line_get(pblk); if (l_mg->data_next) { @@ -969,8 +971,8 @@ struct pblk_line *pblk_recov_l2p(struct pblk *pblk) l_mg->data_next->type = PBLK_LINETYPE_DATA; is_next = 1; } + spin_unlock(&l_mg->free_lock); } - spin_unlock(&l_mg->free_lock); if (is_next) pblk_line_erase(pblk, l_mg->data_next); -- 2.17.1