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=-6.0 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=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 C8500C43381 for ; Mon, 1 Apr 2019 18:10:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 986C82146E for ; Mon, 1 Apr 2019 18:10:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554142244; bh=us4Nj+9dtFwj9PlRB3x0nW0aBqmZvsSlbgRM/Pbvgyo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=V2JH/BsmiILe0kGyZhTX9XTRHLXj4Y+pREqzZ4ePn5vs6YPL5wk9RnX4VCY3n6M3h lGvC2Awe4vKB+d9VOuyMj4UQg1a3NQO+w0cjLM4tO3Sp3Y0CA37XblPiJFLFYsOF69 yxxNfWW6Ct0Yt+VjS3ywb7F0XLNQhWUqqvgZ0fXY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729521AbfDARHl (ORCPT ); Mon, 1 Apr 2019 13:07:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:53954 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729511AbfDARHk (ORCPT ); Mon, 1 Apr 2019 13:07:40 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 1102321934; Mon, 1 Apr 2019 17:07:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554138459; bh=us4Nj+9dtFwj9PlRB3x0nW0aBqmZvsSlbgRM/Pbvgyo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dcQcuLt801kEZSHTPDU2ZihWY8SSvGGoooQd6FB8WNnxahTwIFfemHQW/NALhDzat EXZaiW0nu2aTDitqx6ugSzSKZpZIV1rrH4nEzEEoOHgdoUMiSrriwcfHsxoG1jcm+A dwU5BZxmtzoZULsAEbz2AYibYBHo/qlzCO9m2udU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andreas Schneider , Neil Brown , Jeff Layton Subject: [PATCH 5.0 045/146] locks: wake any locks blocked on request before deadlock check Date: Mon, 1 Apr 2019 19:00:57 +0200 Message-Id: <20190401170052.385151385@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190401170048.449559024@linuxfoundation.org> References: <20190401170048.449559024@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 5.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Layton commit 945ab8f6de94430c23a82f3cf2e3f6d6f2945ff7 upstream. Andreas reported that he was seeing the tdbtorture test fail in some cases with -EDEADLCK when it wasn't before. Some debugging showed that deadlock detection was sometimes discovering the caller's lock request itself in a dependency chain. While we remove the request from the blocked_lock_hash prior to reattempting to acquire it, any locks that are blocked on that request will still be present in the hash and will still have their fl_blocker pointer set to the current request. This causes posix_locks_deadlock to find a deadlock dependency chain when it shouldn't, as a lock request cannot block itself. We are going to end up waking all of those blocked locks anyway when we go to reinsert the request back into the blocked_lock_hash, so just do it prior to checking for deadlocks. This ensures that any lock blocked on the current request will no longer be part of any blocked request chain. URL: https://bugzilla.kernel.org/show_bug.cgi?id=202975 Fixes: 5946c4319ebb ("fs/locks: allow a lock request to block other requests.") Cc: stable@vger.kernel.org Reported-by: Andreas Schneider Signed-off-by: Neil Brown Signed-off-by: Jeff Layton Signed-off-by: Greg Kroah-Hartman --- fs/locks.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/fs/locks.c +++ b/fs/locks.c @@ -1160,6 +1160,11 @@ static int posix_lock_inode(struct inode */ error = -EDEADLK; spin_lock(&blocked_lock_lock); + /* + * Ensure that we don't find any locks blocked on this + * request during deadlock detection. + */ + __locks_wake_up_blocks(request); if (likely(!posix_locks_deadlock(request, fl))) { error = FILE_LOCK_DEFERRED; __locks_insert_block(fl, request,