From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from zeniv.linux.org.uk (zeniv.linux.org.uk [62.89.141.173]) (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 093E6184F; Wed, 31 Jan 2024 00:07:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.89.141.173 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706659660; cv=none; b=JuGg0XaorsM14hBAgXuC1n1oyvnPrXAiz1Ku3wbDII4FEjP81L3nJik6Mj+Ko1Os8Rezu/TBn5Yd+i5vq/7RHrJPOAQKlPPAfKFiSa69iuJnemsHY+0xiYnmyWoBG5s/fOd2hahbvNdnYYKSaWHH1qgshc/qu5f5e1qCTja6UcM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706659660; c=relaxed/simple; bh=Q9vGSke0CeUMqvDrrQjbDeVNJVHShXMK2uoebpMoBEE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gyBs0BTxGGShxQxXwIAfIS3WidOZmmcIf2ZFtH+Iv91wghiKQ20ZOdYpypdS/Za+AkzMZ/vnw6wyBwLYbFOT3DTeok0+oNapk852ecfwFnwTp066V0UKazFEUoXx+1sg34oTPVVOW6oYCA4StYjMiu0syewcDdM9VIUcj3ekAXM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk; spf=none smtp.mailfrom=ftp.linux.org.uk; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b=EUKWUUCT; arc=none smtp.client-ip=62.89.141.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=ftp.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b="EUKWUUCT" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=linux.org.uk; s=zeniv-20220401; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=K5UQD9zZvaq52bbDLYpIpYyrlxYHg6jTjLYeRl++9Vc=; b=EUKWUUCTpVrwKqNrLZx8yQsal4 aH30WA2M/jM9ACLa9/dW9mk8jrsvRMwsee0xg2pjLqdhbJnkIcCWyWxAZVazIuXzvcTvk2kbKmolg 5//JWQp0j5K4nfqSbl3yBeKMVN6MilXhr9jq/LdT8BpLz/e5atE/J2CtPTOlYnF9PnDILU2TZ9GiC Rv4SBCQpTMgG+HdsiJ+yPmeN/gGg2UzQgci4TGJXFSVqxcnT88Mq9CQmdjtO10fdXQixjUNav3a4W NuRnBc9NCe4NX0lpCezck3dlskdipouVz66i1DqblB5UpFBykSB64wljT1g3SSWNKARyOzj6eZFSL 7m/j6CIA==; Received: from viro by zeniv.linux.org.uk with local (Exim 4.96 #2 (Red Hat Linux)) id 1rUy8a-001jn2-2h; Wed, 31 Jan 2024 00:07:32 +0000 Date: Wed, 31 Jan 2024 00:07:32 +0000 From: Al Viro To: Steven Rostedt Cc: Linus Torvalds , Masami Hiramatsu , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH 3/6] tracefs: dentry lookup crapectomy Message-ID: <20240131000732.GM2087318@ZenIV> References: <20240130190355.11486-1-torvalds@linux-foundation.org> <20240130190355.11486-3-torvalds@linux-foundation.org> <20240130232621.GL2087318@ZenIV> <20240130185536.7ff14cb2@gandalf.local.home> Precedence: bulk X-Mailing-List: linux-trace-kernel@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: <20240130185536.7ff14cb2@gandalf.local.home> Sender: Al Viro On Tue, Jan 30, 2024 at 06:55:36PM -0500, Steven Rostedt wrote: > Actually it's the tracefs_start_creating() locks the inode, the > eventfs_start_creating() doesn't. Right. > > > > > if (unlikely(!inode)) > > > return eventfs_failed_creating(dentry); > > > > ... and that still unlocks it. This is still bogus, though - both the stray dput() and dropping a reference to internal mount. struct dentry *eventfs_failed_creating(struct dentry *dentry) { dput(dentry); simple_release_fs(&tracefs_mount, &tracefs_mount_count); return NULL; }