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=-15.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,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 17E8DC4338F for ; Fri, 23 Jul 2021 08:33:29 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8DBD660E77 for ; Fri, 23 Jul 2021 08:33:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 8DBD660E77 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:59262 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m6qcZ-0001Ad-Ev for qemu-devel@archiver.kernel.org; Fri, 23 Jul 2021 04:33:27 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:36862) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m6qbp-0000DG-HY for qemu-devel@nongnu.org; Fri, 23 Jul 2021 04:32:41 -0400 Received: from smtp-out2.suse.de ([195.135.220.29]:53436) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1m6qbn-0003Up-Oj for qemu-devel@nongnu.org; Fri, 23 Jul 2021 04:32:41 -0400 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 46A7C1FF64; Fri, 23 Jul 2021 08:32:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1627029158; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=AL98DLsOGC19VRbMytsvPWsUn5CdWdKP3Nd3YqM3ALc=; b=vRtGCpXEcRJVGq56QFFkP2dx9t+fT8Z5wHN33GwQwXV2sN/HX0Qi3drFUv/BsZwwigMw+R 644TeSMjxhIYWpZMfBxpNe6rfxB7k/cH+liN2hEyTHt3APag+GzDzcztHlez5cxW1GuuXv bF2mt5ZwE5Wjeb04OKgh6G6vhlbhHBI= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1627029158; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=AL98DLsOGC19VRbMytsvPWsUn5CdWdKP3Nd3YqM3ALc=; b=7oOKMC5vCuVdHwcjTHXrWJyqehzu7GWGNC9Yb+dljJDaVqigZk6aXxh08GuCE/VfzRM8Wv rtVrkQc7rIpnsTDQ== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 0347613DF5; Fri, 23 Jul 2021 08:32:37 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id T/3POaV++mAMaQAAMHmgww (envelope-from ); Fri, 23 Jul 2021 08:32:37 +0000 Subject: Re: [PATCH v2 1/1] modules: Improve error message when module is not found To: Markus Armbruster , "Jose R. Ziviani" References: <20210722220952.17444-1-jziviani@suse.de> <20210722220952.17444-2-jziviani@suse.de> <87a6mdcu39.fsf@dusky.pond.sub.org> From: Claudio Fontana Message-ID: Date: Fri, 23 Jul 2021 10:32:37 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <87a6mdcu39.fsf@dusky.pond.sub.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=195.135.220.29; envelope-from=cfontana@suse.de; helo=smtp-out2.suse.de X-Spam_score_int: -45 X-Spam_score: -4.6 X-Spam_bar: ---- X-Spam_report: (-4.6 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.203, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: pbonzini@redhat.com, richard.henderson@linaro.org, qemu-devel@nongnu.org, kraxel@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Hello Markus On 7/23/21 10:28 AM, Markus Armbruster wrote: > "Jose R. Ziviani" writes: > >> When a module is not found, specially accelerators, QEMU displays >> a error message that not easy to understand[1]. This patch improves >> the readability by offering a user-friendly message[2]. >> >> This patch also moves the accelerator ops check to runtine (instead >> of the original g_assert) because it works better with dynamic >> modules. >> >> [1] qemu-system-x86_64 -accel tcg >> ERROR:../accel/accel-softmmu.c:82:accel_init_ops_interfaces: assertion failed: >> (ops != NULL) >> Bail out! ERROR:../accel/accel-softmmu.c:82:accel_init_ops_interfaces: >> assertion failed: (ops != NULL) >> 31964 IOT instruction (core dumped) ./qemu-system-x86_64 ... > > This isn't an error message, it's a crash :) Yes, and the reason of the crash is that the code that needs to initialize ops is missing. The assert needs to _stay there_, this is a symptom, not the cause of the problem, we should not be blindly removing asserts. > >> [2] qemu-system-x86_64 -accel tcg >> accel-tcg-x86_64 module is missing, install the package or config the library path correctly. > > s/config/configure/ > > Also drop the period. > >> >> Signed-off-by: Jose R. Ziviani >> --- >> accel/accel-softmmu.c | 5 ++++- >> util/module.c | 14 ++++++++------ >> 2 files changed, 12 insertions(+), 7 deletions(-) >> >> diff --git a/accel/accel-softmmu.c b/accel/accel-softmmu.c >> index 67276e4f52..52449ac2d0 100644 >> --- a/accel/accel-softmmu.c >> +++ b/accel/accel-softmmu.c >> @@ -79,7 +79,10 @@ void accel_init_ops_interfaces(AccelClass *ac) >> * all accelerators need to define ops, providing at least a mandatory >> * non-NULL create_vcpu_thread operation. >> */ >> - g_assert(ops != NULL); >> + if (ops == NULL) { >> + exit(1); >> + } >> + > > Not your patch's fault: I'm not sure the comment makes sense. Yes, the comment makes sense. > >> if (ops->ops_init) { >> ops->ops_init(ops); >> } >> diff --git a/util/module.c b/util/module.c >> index 6bb4ad915a..268a8563fd 100644 >> --- a/util/module.c >> +++ b/util/module.c >> @@ -206,13 +206,10 @@ static int module_load_file(const char *fname, bool mayfail, bool export_symbols >> out: >> return ret; >> } >> -#endif > > Why do you need to mess with the ifdeffery? > >> >> bool module_load_one(const char *prefix, const char *lib_name, bool mayfail) >> { >> bool success = false; >> - >> -#ifdef CONFIG_MODULES >> char *fname = NULL; >> #ifdef CONFIG_MODULE_UPGRADES >> char *version_dir; >> @@ -300,6 +297,9 @@ bool module_load_one(const char *prefix, const char *lib_name, bool mayfail) >> >> if (!success) { >> g_hash_table_remove(loaded_modules, module_name); >> + fprintf(stderr, "%s module is missing, install the " >> + "package or config the library path " >> + "correctly.\n", module_name); >> g_free(module_name); >> } >> > > Again, not your patch's fault: reporting to stderr with fprintf() is > almost always wrong. > > When the thing we report is an error, we should use error_report() for > correct formatting. Likewise, warn_report() for warnings, info_report() > for informational messages. > > When the module load is triggered by a monitor command, we probably want > to report problems to the monitor. error_report() & friends do the > right thing for HMP. For QMP, you have to use the Error API, i.e. have > the function take an Error ** argument, which the callers propagate all > the way to the QMP core. > > To fix this issue, we first need to decide what kind of message this is: > error, warning, something else. > >> @@ -307,12 +307,9 @@ bool module_load_one(const char *prefix, const char *lib_name, bool mayfail) >> g_free(dirs[i]); >> } >> >> -#endif >> return success; >> } >> >> -#ifdef CONFIG_MODULES >> - >> static bool module_loaded_qom_all; >> >> void module_load_qom_one(const char *type) >> @@ -384,4 +381,9 @@ void qemu_load_module_for_opts(const char *group) {} >> void module_load_qom_one(const char *type) {} >> void module_load_qom_all(void) {} >> >> +bool module_load_one(const char *prefix, const char *lib_name, bool mayfail) >> +{ >> + return false; >> +} >> + >> #endif >