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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 38445C43603 for ; Sat, 7 Dec 2019 16:18:36 +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 EF2F72176D for ; Sat, 7 Dec 2019 16:18:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="NFuWGLd3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EF2F72176D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:50882 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1idcmw-0007m3-UX for qemu-devel@archiver.kernel.org; Sat, 07 Dec 2019 11:18:34 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:57272) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1idcjj-00067x-Vz for qemu-devel@nongnu.org; Sat, 07 Dec 2019 11:15:17 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1idcjg-00048M-EC for qemu-devel@nongnu.org; Sat, 07 Dec 2019 11:15:14 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:20027 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1idcjg-00047u-03 for qemu-devel@nongnu.org; Sat, 07 Dec 2019 11:15:12 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1575735310; h=from:from:reply-to:reply-to:subject:subject: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=RgtK9b3B9Bdcu8CEacjV7/FRXPwRgLumnGE0VYf4yEI=; b=NFuWGLd33bjlQ9HFV2x0SxRhaSHeMNWzhSG+wvWdlHHx2dxlhO/EnPG4FpSjifv4+MzAzQ hdtCrS9akKNifW8W1bh9IeSnqhT/yrfnPJqNf/hEWc5Ffn73RvPgF7OuK9hwlDMOAPy00G exdm22GxHvYC1T264y/eygZniddcov8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-425-5HJDCgOxMEO8Fh7gTZQKfA-1; Sat, 07 Dec 2019 08:14:05 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 05E6A100551C; Sat, 7 Dec 2019 13:14:04 +0000 (UTC) Received: from localhost.localdomain (vpn2-54-34.bne.redhat.com [10.64.54.34]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E1DFE60308; Sat, 7 Dec 2019 13:14:02 +0000 (UTC) Subject: Re: [PATCH] hw/core: Fix data type in do_nmi() To: Greg Kurz References: <20191206063642.40942-1-gshan@redhat.com> <20191206175031.66f62929@bahia.w3ibm.bluemix.net> From: Gavin Shan Message-ID: <8b4e97d1-eddb-b7d2-1069-453ec4a4263a@redhat.com> Date: Sun, 8 Dec 2019 00:14:00 +1100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.0 MIME-Version: 1.0 In-Reply-To: <20191206175031.66f62929@bahia.w3ibm.bluemix.net> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: 5HJDCgOxMEO8Fh7gTZQKfA-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 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: , Reply-To: Gavin Shan Cc: qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 12/7/19 3:50 AM, Greg Kurz wrote: > On Fri, 6 Dec 2019 17:36:42 +1100 > Gavin Shan wrote: > >> object_dynamic_cast() should return machine (or GPIO) state instad of NMI >> state in do_nmi(). So it's wrong to convert it to NMI state unconditionally. >> > > object_dynamic_cast() returns either its first argument if it can be cast > to the given typename or NULL. Since the x86, ccw and spapr machines and > the PowerMac GPIO implement the NMI interface, nothing is wrong here. > > The do_nmi() function is called for all objects in the QOM tree and simply > filters out the ones that don't implement the NMI interface. > > I do agree that this isn't super obvious though. It would be clearer to > do the filtering in the foreach() function. Something like: > > https://patchwork.ozlabs.org/patch/1182232/ > Greg, Thanks for the review and comments. I think we're talking about different issues. I do agree it's worthy to simplify the code with the object_child_foreach_type(), but later. When we have below parameters to qemu, object_dynamic_cast(o, TYPE_NMI) returns object of "pc-q35-4.2-machine", which is passed to the subquent NMIClass::nmi_monitor_handler(). However, the function expects a NMIState from its prototype as below. This patch changes the prototype to fill the gap. void (*nmi_monitor_handler)(NMIState *n, int cpu_index, Error **errp); Changed to: void (*nmi_monitor_handler)(Object *parent, int cpu_index, Error **errp); ~/sandbox/src/qemu/qemu.main.x86/x86_64-softmmu/qemu-system-x86_64 \ --enable-kvm -machine type=q35,accel=kvm,kernel-irqchip=on -cpu host -smp 2 -m 1G \ -monitor none -serial mon:stdio -nographic -s \ -bios ~/sandbox/src/firmware/seabios/out/bios.bin \ -kernel ~/sandbox/src/linux/linux.main.x86/arch/x86/boot/bzImage \ -initrd ~/sandbox/src/util/buildroot/output/images/rootfs.cpio.xz \ -append "earlyprintk=ttyS0 console=ttyS0 debug" \ -device virtio-net-pci,netdev=unet,mac=52:54:00:f1:26:a6 \ -netdev user,id=unet,hostfwd=tcp::50959-:22 \ -drive file=~/sandbox/images/vm.img,if=none,format=raw,id=nvme0 \ -device nvme,drive=nvme0,serial=foo \ -drive file=~/sandbox/images/vm1.img,if=none,format=raw,id=nvme1 \ -device nvme,drive=nvme1,serial=foo1 >> This changes the prototype of NMIClass::nmi_monitor_handler() to accept >> the parent object of NMI state instead of itself. With this, he parent object >> is passed to the function, to avoid potential data corruption. >> >> Signed-off-by: Gavin Shan >> --- >> hw/core/nmi.c | 8 ++++---- >> hw/i386/x86.c | 2 +- >> hw/misc/macio/gpio.c | 6 +++--- >> hw/ppc/spapr.c | 2 +- >> hw/s390x/s390-virtio-ccw.c | 2 +- >> include/hw/nmi.h | 2 +- >> 6 files changed, 11 insertions(+), 11 deletions(-) >> >> diff --git a/hw/core/nmi.c b/hw/core/nmi.c >> index 481c4b3c7e..554708d0db 100644 >> --- a/hw/core/nmi.c >> +++ b/hw/core/nmi.c >> @@ -37,13 +37,13 @@ static void nmi_children(Object *o, struct do_nmi_s *ns); >> static int do_nmi(Object *o, void *opaque) >> { >> struct do_nmi_s *ns = opaque; >> - NMIState *n = (NMIState *) object_dynamic_cast(o, TYPE_NMI); >> + Object *parent = object_dynamic_cast(o, TYPE_NMI); >> >> - if (n) { >> - NMIClass *nc = NMI_GET_CLASS(n); >> + if (parent) { >> + NMIClass *nc = NMI_GET_CLASS(parent); >> >> ns->handled = true; >> - nc->nmi_monitor_handler(n, ns->cpu_index, &ns->err); >> + nc->nmi_monitor_handler(parent, ns->cpu_index, &ns->err); >> if (ns->err) { >> return -1; >> } >> diff --git a/hw/i386/x86.c b/hw/i386/x86.c >> index 394edc2f72..b98204f104 100644 >> --- a/hw/i386/x86.c >> +++ b/hw/i386/x86.c >> @@ -190,7 +190,7 @@ const CPUArchIdList *x86_possible_cpu_arch_ids(MachineState *ms) >> return ms->possible_cpus; >> } >> >> -static void x86_nmi(NMIState *n, int cpu_index, Error **errp) >> +static void x86_nmi(Object *parent, int cpu_index, Error **errp) >> { >> /* cpu index isn't used */ >> CPUState *cs; >> diff --git a/hw/misc/macio/gpio.c b/hw/misc/macio/gpio.c >> index 6cca6b27d6..6b4dfcc188 100644 >> --- a/hw/misc/macio/gpio.c >> +++ b/hw/misc/macio/gpio.c >> @@ -196,10 +196,10 @@ static void macio_gpio_reset(DeviceState *dev) >> macio_set_gpio(s, 1, true); >> } >> >> -static void macio_gpio_nmi(NMIState *n, int cpu_index, Error **errp) >> +static void macio_gpio_nmi(Object *parent, int cpu_index, Error **errp) >> { >> - macio_set_gpio(MACIO_GPIO(n), 9, true); >> - macio_set_gpio(MACIO_GPIO(n), 9, false); >> + macio_set_gpio(MACIO_GPIO(parent), 9, true); >> + macio_set_gpio(MACIO_GPIO(parent), 9, false); >> } >> >> static void macio_gpio_class_init(ObjectClass *oc, void *data) >> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c >> index e076f6023c..3b92e4013d 100644 >> --- a/hw/ppc/spapr.c >> +++ b/hw/ppc/spapr.c >> @@ -3377,7 +3377,7 @@ void spapr_do_system_reset_on_cpu(CPUState *cs, run_on_cpu_data arg) >> ppc_cpu_do_system_reset(cs); >> } >> >> -static void spapr_nmi(NMIState *n, int cpu_index, Error **errp) >> +static void spapr_nmi(Object *parent, int cpu_index, Error **errp) >> { >> CPUState *cs; >> >> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c >> index d3edeef0ad..a49952a8b9 100644 >> --- a/hw/s390x/s390-virtio-ccw.c >> +++ b/hw/s390x/s390-virtio-ccw.c >> @@ -431,7 +431,7 @@ static void s390_hot_add_cpu(MachineState *machine, >> s390x_new_cpu(object_class_get_name(oc), id, errp); >> } >> >> -static void s390_nmi(NMIState *n, int cpu_index, Error **errp) >> +static void s390_nmi(Object *parent, int cpu_index, Error **errp) >> { >> CPUState *cs = qemu_get_cpu(cpu_index); >> >> diff --git a/include/hw/nmi.h b/include/hw/nmi.h >> index a1e128724e..75afa67790 100644 >> --- a/include/hw/nmi.h >> +++ b/include/hw/nmi.h >> @@ -38,7 +38,7 @@ typedef struct NMIState NMIState; >> typedef struct NMIClass { >> InterfaceClass parent_class; >> >> - void (*nmi_monitor_handler)(NMIState *n, int cpu_index, Error **errp); >> + void (*nmi_monitor_handler)(Object *parent, int cpu_index, Error **errp); >> } NMIClass; >> >> void nmi_monitor_handle(int cpu_index, Error **errp); > Regards, Gavin