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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 74E16D7877D for ; Thu, 21 Nov 2024 15:21:38 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tE8zI-0002n5-8A; Thu, 21 Nov 2024 10:20:56 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tE8zG-0002mD-3w for qemu-devel@nongnu.org; Thu, 21 Nov 2024 10:20:54 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tE8zE-0005Gw-B0 for qemu-devel@nongnu.org; Thu, 21 Nov 2024 10:20:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1732202451; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=NsgngFd0oKM3uJ0uRCOdxMUjEO3tFe3+cW3jqA5wdlY=; b=Qgz9U/aJf9HW30n4SSjywqGQCC6hAN4lsfeqiOoj084R+Kt0gJhTfQ6iRjhwHw+LNXEPoi 0XqufoZ6HL61FoFFjsWVY/yaxmBIaA47kYsiBUHpiHTe89CJmBNubbUatcegTMf+J7k8aE YbQdiFRm2jtxDyMUh8oowAXQczyFWWA= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-130-dBrYlWb7PhaNd5Wwk9X-4Q-1; Thu, 21 Nov 2024 10:20:48 -0500 X-MC-Unique: dBrYlWb7PhaNd5Wwk9X-4Q-1 X-Mimecast-MFC-AGG-ID: dBrYlWb7PhaNd5Wwk9X-4Q Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E36C61956096; Thu, 21 Nov 2024 15:20:46 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.194.95]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id BC9B319560A3; Thu, 21 Nov 2024 15:20:44 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 89E5921E6A28; Thu, 21 Nov 2024 16:20:42 +0100 (CET) From: Markus Armbruster To: Kevin Wolf Cc: qemu-devel@nongnu.org, peter.maydell@linaro.org, pbonzini@redhat.com, berrange@redhat.com, eduardo@habkost.net, qemu-stable@nongnu.org Subject: Re: [PATCH] qdev: Fix set_pci_devfn() to visit option only once In-Reply-To: <20241119120353.57812-1-kwolf@redhat.com> (Kevin Wolf's message of "Tue, 19 Nov 2024 13:03:53 +0100") References: <20241119120353.57812-1-kwolf@redhat.com> Date: Thu, 21 Nov 2024 16:20:42 +0100 Message-ID: <87plmohaut.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.14, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Kevin Wolf writes: > pci_devfn properties accept either a string or an integer as input. To > implement this, set_pci_devfn() first tries to visit the option as a > string, and if that fails, it visits it as an integer instead. While the > QemuOpts visitor happens to accept this, it is invalid according to the > visitor interface. QObject input visitors run into an assertion failure > when this is done. > > QObject input visitors are used with the JSON syntax version of -device > on the command line: > > $ ./qemu-system-x86_64 -enable-kvm -M q35 -device pcie-pci-bridge,id=pci.1,bus=pcie.0 -blockdev null-co,node-name=disk -device '{ "driver": "virtio-blk-pci", "drive": "disk", "id": "virtio-disk0", "bus": "pci.1", "addr": 1 }' > qemu-system-x86_64: ../qapi/qobject-input-visitor.c:143: QObject *qobject_input_try_get_object(QObjectInputVisitor *, const char *, _Bool): Assertion `removed' failed. > > The proper way to accept both strings and integers is using the > alternate mechanism, which tells us the type of the input before it's > visited. With this information, we can directly visit it as the right > type. > > This fixes set_pci_devfn() by using the alternate mechanism. > > Cc: qemu-stable@nongnu.org > Reported-by: Peter Maydell > Signed-off-by: Kevin Wolf > --- > hw/core/qdev-properties-system.c | 54 +++++++++++++++++++++----------- > 1 file changed, 36 insertions(+), 18 deletions(-) > > diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c > index 35deef05f3..91d3ff4719 100644 > --- a/hw/core/qdev-properties-system.c > +++ b/hw/core/qdev-properties-system.c > @@ -790,39 +790,57 @@ static void set_pci_devfn(Object *obj, Visitor *v, const char *name, > void *opaque, Error **errp) > { > Property *prop = opaque; > + GenericAlternate *alt; > int32_t value, *ptr = object_field_prop_ptr(obj, prop); > unsigned int slot, fn, n; > - char *str; > + g_autofree char *str = NULL; > + > + if (!visit_start_alternate(v, name, &alt, sizeof(*alt), errp)) { > + return; > + } > + > + switch (alt->type) { > + case QTYPE_QSTRING: > + if (!visit_type_str(v, name, &str, errp)) { > + goto out; > + } > > - if (!visit_type_str(v, name, &str, NULL)) { > + if (sscanf(str, "%x.%x%n", &slot, &fn, &n) != 2) { > + fn = 0; > + if (sscanf(str, "%x%n", &slot, &n) != 1) { > + goto invalid; > + } > + } > + if (str[n] != '\0' || fn > 7 || slot > 31) { > + goto invalid; > + } > + *ptr = slot << 3 | fn; > + break; > + > + case QTYPE_QNUM: > if (!visit_type_int32(v, name, &value, errp)) { > - return; > + goto out; > } > if (value < -1 || value > 255) { > error_setg(errp, QERR_INVALID_PARAMETER_VALUE, > name ? name : "null", "a value between -1 and 255"); > - return; > + goto out; > } > *ptr = value; > - return; > - } > + break; > > - if (sscanf(str, "%x.%x%n", &slot, &fn, &n) != 2) { > - fn = 0; > - if (sscanf(str, "%x%n", &slot, &n) != 1) { > - goto invalid; > - } > - } > - if (str[n] != '\0' || fn > 7 || slot > 31) { > - goto invalid; > + default: > + error_setg(errp, "Invalid parameter type for '%s', expected int or str", > + name ? name : "null"); > + goto out; This goto is redundant. > } > - *ptr = slot << 3 | fn; > - g_free(str); > - return; > + > + goto out; > > invalid: > error_set_from_qdev_prop_error(errp, EINVAL, obj, name, str); > - g_free(str); > +out: > + visit_end_alternate(v, (void **) &alt); > } > > static int print_pci_devfn(Object *obj, Property *prop, char *dest, Ugly control flow, but cleaning that up is not the patch's goal. Instead, it aims to just fix the bug. Fair. Reviewed-by: Markus Armbruster