From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from outgoing.mit.edu (outgoing-auth-1.mit.edu [18.9.28.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 41AAA14B09F for ; Thu, 13 Jun 2024 21:57:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=18.9.28.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718315856; cv=none; b=AjExbC3O5/Ons9J66ud0aU1teKxColXj97RJxsfJGGuR+KTUP3WeOdcXKxldvDcIXhLlbWQ7kjnuwT6STrLLNa5lPByaYqtWYd40NU3e3WseMHMYgBaVyfYmboFmcgvzUAocLNMl73DTzXr87DrlGXsdsASJ1F3lI0QbyA11m5w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718315856; c=relaxed/simple; bh=1H4KUBPxpm8hVaGmrXkqGRToMuoTEDG2zah8EkagM2Y=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VfuNQqgdrXoge0SJH9bJF53Umm01+lcW1meGBnHo7oBzwNHwQjA9/Wr6hos762MEWMcGJfsVMcmXzKVaA1mgdn7xeHkb79E6d9ONTE4aWZLJmJl5gI5GO8kN/OBvErj3DF7JVBWDfjlRSRWMAbJV2DKJ5SSHcpPWpcQI3Lyc4V8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=mit.edu; spf=pass smtp.mailfrom=mit.edu; dkim=pass (2048-bit key) header.d=mit.edu header.i=@mit.edu header.b=iS/pjxIw; arc=none smtp.client-ip=18.9.28.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=mit.edu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mit.edu Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mit.edu header.i=@mit.edu header.b="iS/pjxIw" Received: from macsyma.thunk.org ([204.93.149.86]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 45DLuvLw029951 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 13 Jun 2024 17:57:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mit.edu; s=outgoing; t=1718315832; bh=jEzJNwHQDxbRySEdEpZpwvnORAbr8LsWzKdES99EzUw=; h=Date:From:Subject:Message-ID:MIME-Version:Content-Type; b=iS/pjxIw3aaB+Xl4h+y+yyz3o/3Pd74lA8BsE95EF2RWsy0GF96PtZ5dusXuCYNh0 bLS/brjZ+vvnRHmctoiZJgeQPC2m1ClyEQ+pY+m1QwJ/DWQjnPBjAlulwuZsPUT87X RIuU0+rvJQ+Lm2RDxuWmmZ1sc1WjR3DqgC9kI2iJfhO7bEgiPnODsGfl0uxWMN6DLh LiqZ4JX1YZwyxEENWpE3YUG0CNjpJjRKoSGR8qGwcdlOno8F0z6tzUdsviHbrpQ9V3 aJ66umICT4RLW4bV1hQ0W9DQWBNWeuGIxiKsvY6uWxmJV7ZF8DWO4V21hevsezr+k9 68F7qdHP0AC8g== Received: by macsyma.thunk.org (Postfix, from userid 15806) id B52F134169C; Thu, 13 Jun 2024 23:56:39 +0200 (CEST) Date: Thu, 13 Jun 2024 22:56:39 +0100 From: "Theodore Ts'o" To: "Darrick J. Wong" Cc: Linux Filesystem Development List , fstests@vger.kernel.org Subject: Re: Flaky test: generic:269 (EBUSY on umount) Message-ID: <20240613215639.GE1906022@mit.edu> References: <20240612162948.GA2093190@mit.edu> <20240612194136.GA2764780@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240612194136.GA2764780@frogsfrogsfrogs> On Wed, Jun 12, 2024 at 12:41:36PM -0700, Darrick J. Wong wrote: > > I don't see this problem; if you apply this to fstests to turn off > io_uring: > https://lore.kernel.org/fstests/169335095953.3534600.16325849760213190849.stgit@frogsfrogsfrogs/#r > > do the problems go away? Thanks for pointing out the mail thread; I had a vague memory that this had been raised as a problem before. Looking at the discussion (from August 2023, so over 9 months ago), this is a bug that has been acknowledged as an io_uring bug, but it still hasn't been fixed. Using Zorro's sugestion of adding "-f uring_read=0 -f uring_write=0" to the fsstress options makes the EBUSY umount failures go away. I've also created a new test which relaibly reproduces the "fsstress ; umount" EBUSY bug (as opposed to the existing test failures which only fail 1-10% of the time). So with that I can with a clean conscience suggest that we omit io_uring calls from those tests using fsstress to thest some non-io_uring related bug if they run into the umount EBUSY bug, since there is now a new bug which reliably shows off the problem.... - Ted