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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 3807CC64E7A for ; Tue, 17 Nov 2020 13:43:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD09C206A5 for ; Tue, 17 Nov 2020 13:43:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="kyRSLbgw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733026AbgKQNme (ORCPT ); Tue, 17 Nov 2020 08:42:34 -0500 Received: from mail.kernel.org ([198.145.29.99]:53488 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732521AbgKQNlM (ORCPT ); Tue, 17 Nov 2020 08:41:12 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 DDFA120870; Tue, 17 Nov 2020 13:41:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605620471; bh=XGQzUUIqVdnBFX5aIgJkBe9k651L/X8WLIcid+bDbdQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kyRSLbgwSSnD3ReRiG3Z2U8x5kWwbRmD8Dc8KlBPx2j5UmkEMIYSxXkMRq9dqLUOp hqbz0RSJkQUfrjIeqqbxrZZX+RJocNGgHnO0KPD2MjQjYJhtMxnnNiHTkeWP7AakAX 578DTCxI6D8scX5qARbQo7lRqkH/VSwc1NbV/rUo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kris Karas , "J. Bruce Fields" , Anna Schumaker Subject: [PATCH 5.9 231/255] NFSv4.2: fix failure to unregister shrinker Date: Tue, 17 Nov 2020 14:06:11 +0100 Message-Id: <20201117122150.181446172@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201117122138.925150709@linuxfoundation.org> References: <20201117122138.925150709@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: J. Bruce Fields commit 70438afbf17e5194dd607dd17759560a363b7bb4 upstream. 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 Fixes: 95ad37f90c33 "NFSv4.2: add client side xattr caching." Signed-off-by: J. Bruce Fields CC: stable@vger.kernel.org Signed-off-by: Anna Schumaker Signed-off-by: Greg Kroah-Hartman --- fs/nfs/nfs42xattr.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/nfs/nfs42xattr.c +++ b/fs/nfs/nfs42xattr.c @@ -1048,8 +1048,10 @@ out4: 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);