From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 633F02D5938; Wed, 3 Sep 2025 06:08:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756879713; cv=none; b=udQqxrwRjXsGpUBPV1BE4+8CFYhuDI4ylj0Lh9eysCe9qRo22OuzsJw0qqijGuhiLuAB86l4At2ZNIH6dOz3y7rYc2amtPC0AW/2UpDSmPBkCxU/0O1sGr/qBguGTt5cA2zPbcl3X7tdHaxd6jvPqLD52mlS827jQe6Z+gZagBI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756879713; c=relaxed/simple; bh=xoXZ8fI6UslXlNQFkGXP2ovZvb7oU9JUnj0hhiY1+q4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=m7xkFbRrzvJoZEclbMk+865VkPvV85P0hgsEtJ43qcKVfzl40MDkwCTUMvZqi7AvPXF8hAvstJjE+ohME6nHTc82qopaVoymDYPiLPjuUrz3hgnxhoGlS4Qjlr/Hpje0P4i/tUBqOW07jKgaQz/aJzhO7iTIcJi6FOSYEPn4STA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=vB0ywPsi; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="vB0ywPsi" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=L851IHbqrVpIrG6uFeEojRb7BABVfLuDX9yKbnxc82M=; b=vB0ywPsi0BiQ0RcWLFCg4b9CXM 8tfr/Yz9TErvtAmM90+NrYZsMZpdOe5SGTMu4slh80l/mmthTGXCrW8G5Gp4wCnPh9kB2wlptISfP Bc1OwxOzR6Z8fklu+6YKwonvY7CxxD7/SU/Nm4wocgKLdYA3IYrP59xOFDgneKbDyerNCsyxN/rLs W8A54YkMxXQt61lsuEr5TTemAOKc7pkiiuWH6aHcyX6VnJICvu0YHlRy/07zZf9zOFiMIVApAVKIW v0A0j8tl2GP062oziB2w0j76xrP5OhDLrvO5/5aQaGSsSn5zRZXEvHSoG8rWpXmO5h0VZ0bovgy4m Q6ceWpug==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1utgfX-00000004Tjn-3wiY; Wed, 03 Sep 2025 06:08:31 +0000 Date: Tue, 2 Sep 2025 23:08:31 -0700 From: Christoph Hellwig To: Dave Chinner Cc: syzbot , cem@kernel.org, linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [xfs?] KASAN: slab-use-after-free Read in xfs_buf_rele (4) Message-ID: References: <68b6d7b3.050a0220.3db4df.01cf.GAE@google.com> Precedence: bulk X-Mailing-List: linux-xfs@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: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Wed, Sep 03, 2025 at 11:05:57AM +1000, Dave Chinner wrote: > I think that the buftarg rhashtable needs to initialised before the > shrinker is registered, then freed from xfs_destroy_buftarg() after > the shrinker has been shut down as it must live longer than the > buftarg shrinker instance. i.e. the buftarg rhashtable needs to have > the same life cycle as the buftarg LRU list.... My RFC patch to switch back to a per-buftarg hashtable would do that: https://git.infradead.org/?p=users/hch/xfs.git;a=commitdiff;h=e3cc537864a7ab980abfa18a3efe01a111aad1d7 I still haven't gotten around doing serious performance testing on it, and I'm busy right now. But in about two weeks I'll probably have both a bit of time and access to a big enough system to do serious scalability testing on it.