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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 EE699C76190 for ; Fri, 26 Jul 2019 13:45:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C753B22CBF for ; Fri, 26 Jul 2019 13:45:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564148731; bh=PAj6zUAmFM17o7AjZUCKjS16bLP6pFFJOAO8OFZD/kA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=cuOU2c3rzAl7yY7PieykvUpoVgulswgn54TffTVu0Zy9Uq2uEH7U3WLqiFP9NgPUL S7KrAman4DrPQkIXzI5ugGYNif5hTLJt6d3GweyYotcm1El8Y8ZFf3BkshZRizkhSb hh3b4CsjH+Rc91YkFGxbDBYSVxLX8CKFsuetlXCY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728145AbfGZNpa (ORCPT ); Fri, 26 Jul 2019 09:45:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:54428 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387751AbfGZNp1 (ORCPT ); Fri, 26 Jul 2019 09:45:27 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8436022CE9; Fri, 26 Jul 2019 13:45:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564148726; bh=PAj6zUAmFM17o7AjZUCKjS16bLP6pFFJOAO8OFZD/kA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XXnhMX4a6L00XqDxq3b64jp6IHRknimgdSxLtVzyoSBYhRRak+crqrBopgySO9BWz 0+ws/lG1bOkPvH7aqJ6jrq5HLbWdeZeU1XOMJeqaCeS60k6FtvHOw62C4vjKB7yQ5g DNhuO93VPUkyJjTpaWxgRim+Sj9A0E+e0pREfmAc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Prarit Bhargava , Barret Rhoden , David Arcari , Jessica Yu , Heiko Carstens , Sasha Levin Subject: [PATCH AUTOSEL 4.4 03/23] kernel/module.c: Only return -EEXIST for modules that have finished loading Date: Fri, 26 Jul 2019 09:45:02 -0400 Message-Id: <20190726134522.13308-3-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190726134522.13308-1-sashal@kernel.org> References: <20190726134522.13308-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Prarit Bhargava [ Upstream commit 6e6de3dee51a439f76eb73c22ae2ffd2c9384712 ] Microsoft HyperV disables the X86_FEATURE_SMCA bit on AMD systems, and linux guests boot with repeated errors: amd64_edac_mod: Unknown symbol amd_unregister_ecc_decoder (err -2) amd64_edac_mod: Unknown symbol amd_register_ecc_decoder (err -2) amd64_edac_mod: Unknown symbol amd_report_gart_errors (err -2) amd64_edac_mod: Unknown symbol amd_unregister_ecc_decoder (err -2) amd64_edac_mod: Unknown symbol amd_register_ecc_decoder (err -2) amd64_edac_mod: Unknown symbol amd_report_gart_errors (err -2) The warnings occur because the module code erroneously returns -EEXIST for modules that have failed to load and are in the process of being removed from the module list. module amd64_edac_mod has a dependency on module edac_mce_amd. Using modules.dep, systemd will load edac_mce_amd for every request of amd64_edac_mod. When the edac_mce_amd module loads, the module has state MODULE_STATE_UNFORMED and once the module load fails and the state becomes MODULE_STATE_GOING. Another request for edac_mce_amd module executes and add_unformed_module() will erroneously return -EEXIST even though the previous instance of edac_mce_amd has MODULE_STATE_GOING. Upon receiving -EEXIST, systemd attempts to load amd64_edac_mod, which fails because of unknown symbols from edac_mce_amd. add_unformed_module() must wait to return for any case other than MODULE_STATE_LIVE to prevent a race between multiple loads of dependent modules. Signed-off-by: Prarit Bhargava Signed-off-by: Barret Rhoden Cc: David Arcari Cc: Jessica Yu Cc: Heiko Carstens Signed-off-by: Jessica Yu Signed-off-by: Sasha Levin --- kernel/module.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/kernel/module.c b/kernel/module.c index bcc78f4c15e9..b940b2825b7b 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3225,8 +3225,7 @@ static bool finished_loading(const char *name) sched_annotate_sleep(); mutex_lock(&module_mutex); mod = find_module_all(name, strlen(name), true); - ret = !mod || mod->state == MODULE_STATE_LIVE - || mod->state == MODULE_STATE_GOING; + ret = !mod || mod->state == MODULE_STATE_LIVE; mutex_unlock(&module_mutex); return ret; @@ -3385,8 +3384,7 @@ static int add_unformed_module(struct module *mod) mutex_lock(&module_mutex); old = find_module_all(mod->name, strlen(mod->name), true); if (old != NULL) { - if (old->state == MODULE_STATE_COMING - || old->state == MODULE_STATE_UNFORMED) { + if (old->state != MODULE_STATE_LIVE) { /* Wait in case it fails to load. */ mutex_unlock(&module_mutex); err = wait_event_interruptible(module_wq, -- 2.20.1