From: Markus Armbruster <armbru@redhat.com>
To: "Philippe Mathieu-Daudé" <philmd@redhat.com>
Cc: "Peter Maydell" <peter.maydell@linaro.org>,
"Marcelo Tosatti" <mtosatti@redhat.com>,
"Daniel P. Berrangé" <berrange@redhat.com>,
"Eduardo Habkost" <ehabkost@redhat.com>,
"Like Xu" <like.xu@linux.intel.com>,
"David Hildenbrand" <david@redhat.com>,
"Cornelia Huck" <cohuck@redhat.com>,
qemu-devel@nongnu.org, qemu-s390x@nongnu.org,
qemu-arm@nongnu.org, qemu-ppc@nongnu.org,
"Paolo Bonzini" <pbonzini@redhat.com>,
"David Gibson" <david@gibson.dropbear.id.au>,
"Richard Henderson" <rth@twiddle.net>
Subject: Re: [PATCH v2 07/10] qdev: Abort if the root machine container is missing
Date: Tue, 21 Jan 2020 13:45:06 +0100 [thread overview]
Message-ID: <87k15ldlm5.fsf@dusky.pond.sub.org> (raw)
In-Reply-To: <20200121110349.25842-8-philmd@redhat.com> ("Philippe =?utf-8?Q?Mathieu-Daud=C3=A9=22's?= message of "Tue, 21 Jan 2020 12:03:46 +0100")
Philippe Mathieu-Daudé <philmd@redhat.com> writes:
> The QEMU device API (qdev) relies on having the '/machine'
> container always available.
>
> If it is missing, QEMU will later crash dereferencing a NULL
> pointer, we will get a SEGV, open a debugger, look at the
> backtrace, and figure out we messed with QOM.
> Or we can use g_assert() which abort, displaying the filename
> and line number, so we can quickly open our favorite IDE.
> Prefer the later, to save time to developers.
>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> v2: New patch
> ---
> hw/core/qdev.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/hw/core/qdev.c b/hw/core/qdev.c
> index 58e87d336d..d30cf6320b 100644
> --- a/hw/core/qdev.c
> +++ b/hw/core/qdev.c
> @@ -1143,6 +1143,7 @@ Object *qdev_get_machine(void)
>
> if (dev == NULL) {
> dev = container_get(object_get_root(), "/machine");
> + g_assert(dev != NULL);
> }
>
> return dev;
container_get()'s contract promises it won't return null. I think the
assertion belongs there instead.
next prev parent reply other threads:[~2020-01-21 13:54 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-21 11:03 [PATCH v2 00/10] Cleanups around the 'current_machine' global variable Philippe Mathieu-Daudé
2020-01-21 11:03 ` [PATCH v2 01/10] hw/ppc/spapr_rtas: Use local MachineState variable Philippe Mathieu-Daudé
2020-01-21 11:03 ` [PATCH v2 02/10] hw/ppc/spapr_rtas: Access MachineState via SpaprMachineState argument Philippe Mathieu-Daudé
2020-01-21 11:03 ` [PATCH v2 03/10] hw/ppc/spapr_rtas: Remove local variable Philippe Mathieu-Daudé
2020-01-22 3:27 ` David Gibson
2020-01-21 11:03 ` [PATCH v2 04/10] target/arm/kvm: Use CPUState::kvm_state in kvm_arm_pmu_supported() Philippe Mathieu-Daudé
2020-01-21 11:03 ` [PATCH v2 05/10] target/s390x: Remove duplicated ifdef macro Philippe Mathieu-Daudé
2020-01-21 13:52 ` Cornelia Huck
2020-01-21 16:45 ` Cornelia Huck
2020-01-21 11:03 ` [PATCH v2 06/10] qom/object: Display more helpful message when a parent is missing Philippe Mathieu-Daudé
2020-01-21 13:54 ` Cornelia Huck
2020-01-21 11:03 ` [PATCH v2 07/10] qdev: Abort if the root machine container " Philippe Mathieu-Daudé
2020-01-21 12:45 ` Markus Armbruster [this message]
2020-01-21 11:03 ` [PATCH v2 08/10] accel: Introduce the current_accel() wrapper Philippe Mathieu-Daudé
2020-01-21 13:56 ` Cornelia Huck
2020-01-21 11:03 ` [PATCH v2 09/10] accel: Replace current_machine->accelerator by " Philippe Mathieu-Daudé
2020-01-21 14:03 ` Cornelia Huck
2020-01-22 3:28 ` David Gibson
2020-01-21 11:03 ` [PATCH v2 10/10] accel/tcg: Sanitize include path Philippe Mathieu-Daudé
2020-01-21 14:06 ` Cornelia Huck
2020-01-21 12:47 ` [PATCH v2 00/10] Cleanups around the 'current_machine' global variable Markus Armbruster
2020-01-21 12:49 ` Philippe Mathieu-Daudé
2020-01-21 16:27 ` Paolo Bonzini
2020-01-21 16:44 ` Cornelia Huck
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