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Ziviani" References: <20210720223120.21711-1-jziviani@suse.de> <20210720223120.21711-3-jziviani@suse.de> From: Claudio Fontana Message-ID: Date: Wed, 21 Jul 2021 11:57:57 +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: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=195.135.220.29; envelope-from=cfontana@suse.de; helo=smtp-out2.suse.de X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 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=-0.001, 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, ehabkost@redhat.com, kraxel@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 7/21/21 11:34 AM, Daniel P. Berrangé wrote: > On Tue, Jul 20, 2021 at 07:31:20PM -0300, Jose R. Ziviani wrote: >> module_object_class_by_name() calls module_load_qom_one if the object >> is provided by a dynamically linked library. Such library might not be >> available at this moment - for instance, it can be a package not yet >> installed. Thus, instead of assert error messages, this patch outputs >> more friendly messages. >> >> Current error messages: >> $ ./qemu-system-x86_64 -machine q35 -accel tcg -kernel /boot/vmlinuz >> ... >> 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) >> [1] 31964 IOT instruction (core dumped) ./qemu-system-x86_64 ... >> >> New error message: >> $ ./qemu-system-x86_64 -machine q35 -accel tcg -kernel /boot/vmlinuz >> accel-tcg-x86_64 module is missing, install the package or config the library path correctly. >> >> Or with other modules, when possible: >> $ ./qemu-system-x86_64 -machine q35 -accel kvm -kernel /boot/vmlinuz -vga qxl ✹ >> hw-display-qxl module is missing, install the package or config the library path correctly. >> qemu-system-x86_64: QXL VGA not available >> >> $ make check >> ... >> Running test qtest-x86_64/test-filter-mirror >> Running test qtest-x86_64/endianness-test >> accel-qtest-x86_64 module is missing, install the package or config the library path correctly. >> accel-qtest-x86_64 module is missing, install the package or config the library path correctly. >> accel-qtest-x86_64 module is missing, install the package or config the library path correctly. >> accel-qtest-x86_64 module is missing, install the package or config the library path correctly. >> accel-qtest-x86_64 module is missing, install the package or config the library path correctly. >> accel-tcg-x86_64 module is missing, install the package or config the library path correctly. >> ... >> >> Signed-off-by: Jose R. Ziviani >> --- >> accel/accel-softmmu.c | 5 ++++- >> qom/object.c | 9 +++++++++ >> 2 files changed, 13 insertions(+), 1 deletion(-) >> >> 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); >> + } >> + >> if (ops->ops_init) { >> ops->ops_init(ops); >> } >> diff --git a/qom/object.c b/qom/object.c >> index 6a01d56546..3a170ea9df 100644 >> --- a/qom/object.c >> +++ b/qom/object.c >> @@ -10,6 +10,7 @@ >> * See the COPYING file in the top-level directory. >> */ >> >> +#include "qemu/module.h" >> #include "qemu/osdep.h" >> #include "hw/qdev-core.h" >> #include "qapi/error.h" >> @@ -1031,8 +1032,16 @@ ObjectClass *module_object_class_by_name(const char *typename) >> oc = object_class_by_name(typename); >> #ifdef CONFIG_MODULES >> if (!oc) { >> + const char *module_name = module_get_name_from_obj(typename); >> module_load_qom_one(typename); >> oc = object_class_by_name(typename); >> + if (!oc && module_name) { >> + if (!module_is_loaded(module_name)) { >> + fprintf(stderr, "%s module is missing, install the " >> + "package or config the library path " >> + "correctly.\n", module_name); >> + } >> + } >> } > > Introducing a call to module_is_loaded is feels like it isn't really > addressing the root cause. > > The error scenario here exists because module_load_qom_one() can > fail to load the requested module. We don't detect that failure > because module_load_qom_one() is "void" for some reason. There > are several possible causes of failure and missing file on disk > is only one of them. > > This general error message about "module_name" being missing is > misleading when there are dependancies involved. "module_name" > may well exist, but something it depends on might be missing. > Or the modules might have been built from wrong QEMU and be > unable to be dlopened despite existing. > > I think we need to fix module_load_qom_one() so that it can > actually report failure via an "Error **errp" parameter. Sounds right to me. > This will also entail fixing a number of methods it in turn > calls. > > > Regards, > Daniel > Thanks, Claudio