| Message ID | 20210720223120.21711-3-jziviani@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Improve module accelerator error message | expand |
On 7/21/21 12:31 AM, 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 <jziviani@suse.de> > --- > 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); > + } > + Why? > 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); > + } > + } > } > #endif > return oc; >
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 <jziviani@suse.de> > --- > 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. This will also entail fixing a number of methods it in turn calls. Regards, Daniel
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 <jziviani@suse.de> >> --- >> 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
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); + } + } } #endif return oc;
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 <jziviani@suse.de> --- accel/accel-softmmu.c | 5 ++++- qom/object.c | 9 +++++++++ 2 files changed, 13 insertions(+), 1 deletion(-)