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=-11.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 AC8A5C2D0A3 for ; Thu, 12 Nov 2020 14:03:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0DCF820A8B for ; Thu, 12 Nov 2020 14:03:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fieldses.org header.i=@fieldses.org header.b="vg29WQ88" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728089AbgKLODl (ORCPT ); Thu, 12 Nov 2020 09:03:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55088 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727646AbgKLODl (ORCPT ); Thu, 12 Nov 2020 09:03:41 -0500 Received: from fieldses.org (fieldses.org [IPv6:2600:3c00:e000:2f7::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 46BB2C0613D1 for ; Thu, 12 Nov 2020 06:03:41 -0800 (PST) Received: by fieldses.org (Postfix, from userid 2815) id B1ECF200D; Thu, 12 Nov 2020 09:03:40 -0500 (EST) DKIM-Filter: OpenDKIM Filter v2.11.0 fieldses.org B1ECF200D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fieldses.org; s=default; t=1605189820; bh=2WIRvPt7Vxd+c58TxlOYQDoAfAYi3ZLfBSJaYTEfQkQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vg29WQ88y7/pUFkIEvrlm7tFZX1/ZWC1Brp50/qFublVnVUo0Wkc0heNs0jKESm/n WRFuz3rfKH0xhAINZrDt7hcxydAPPSdDNi75XHiqG7IbCjlwC/oBulqLpqjIctwZ+6 Fh+KCX3GJyQ9QVn4ltEHEMvrRnfY9IT7We32ogR8= Date: Thu, 12 Nov 2020 09:03:40 -0500 From: "J. Bruce Fields" To: Trond Myklebust , Anna Schumaker Cc: linux-nfs@vger.kernel.org Subject: Re: [PATCH] NFSv4.2: fix failure to unregister shrinker Message-ID: <20201112140340.GB9243@fieldses.org> References: <20201021143415.GA27122@fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201021143415.GA27122@fieldses.org> User-Agent: Mutt/1.5.21 (2010-09-15) Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Looks like this patch got lost, do you need me to resend? I should also have added a stable cc and a Fixes: 95ad37f90c33 "NFSv4.2: add client side xattr caching." --b. On Wed, Oct 21, 2020 at 10:34:15AM -0400, bfields wrote: > From: "J. Bruce Fields" > > We forgot to unregister the nfs4_xattr_large_entry_shrinker. > > That leaves the global list of shrinkers corrupted after unload of the > nfs module, after which possibly unrelated code that calls > register_shrinker() or unregister_shrinker() gets a BUG() with > "supervisor write access in kernel mode". > > And similarly for the nfs4_xattr_large_entry_lru. > > Reported-by: Kris Karas > Tested-By: Kris Karas > Signed-off-by: J. Bruce Fields > --- > fs/nfs/nfs42xattr.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/fs/nfs/nfs42xattr.c b/fs/nfs/nfs42xattr.c > index 86777996cfec..55b44a42d625 100644 > --- a/fs/nfs/nfs42xattr.c > +++ b/fs/nfs/nfs42xattr.c > @@ -1048,8 +1048,10 @@ int __init nfs4_xattr_cache_init(void) > > void nfs4_xattr_cache_exit(void) > { > + unregister_shrinker(&nfs4_xattr_large_entry_shrinker); > unregister_shrinker(&nfs4_xattr_entry_shrinker); > unregister_shrinker(&nfs4_xattr_cache_shrinker); > + list_lru_destroy(&nfs4_xattr_large_entry_lru); > list_lru_destroy(&nfs4_xattr_entry_lru); > list_lru_destroy(&nfs4_xattr_cache_lru); > kmem_cache_destroy(nfs4_xattr_cache_cachep); > -- > 2.26.2 >