From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from list by lists.gnu.org with archive (Exim 4.71) id 1dt8AM-0007Mx-F3 for mharc-qemu-trivial@gnu.org; Sat, 16 Sep 2017 04:09:30 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36071) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dt8AJ-0007L2-Ec for qemu-trivial@nongnu.org; Sat, 16 Sep 2017 04:09:28 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dt8AI-0002Kn-A5 for qemu-trivial@nongnu.org; Sat, 16 Sep 2017 04:09:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45946) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dt8AB-0002JX-Tg; Sat, 16 Sep 2017 04:09:20 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2A3BA61461; Sat, 16 Sep 2017 08:09:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 2A3BA61461 Authentication-Results: ext-mx10.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx10.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=pbonzini@redhat.com Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 13AAA39BD; Sat, 16 Sep 2017 08:09:16 +0000 (UTC) Received: from zmail18.collab.prod.int.phx2.redhat.com (zmail18.collab.prod.int.phx2.redhat.com [10.5.83.21]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id BFB9D1808872; Sat, 16 Sep 2017 08:09:15 +0000 (UTC) Date: Sat, 16 Sep 2017 04:09:15 -0400 (EDT) From: Paolo Bonzini To: Eduardo Habkost Cc: Eduardo Otubo , qemu-devel@nongnu.org, qemu-trivial@nongnu.org, Michael Tokarev , Markus Armbruster , Alexander Graf Message-ID: <2144615425.6261195.1505549355346.JavaMail.zimbra@redhat.com> In-Reply-To: <20170915222113.GB10621@localhost.localdomain> References: <20170915090643.6043-1-otubo@redhat.com> <0d4bdcbb-3153-0064-d280-d9ca4f0671e4@redhat.com> <20170915222113.GB10621@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [78.12.246.117, 10.4.196.5, 10.4.195.12] Thread-Topic: dma/i82374: avoid double creation of i82374 device Thread-Index: 8Mxpho57qGQUR3vD6+No3YJBqJM8qg== X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Sat, 16 Sep 2017 08:09:18 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-trivial] [PATCH] dma/i82374: avoid double creation of i82374 device X-BeenThere: qemu-trivial@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 16 Sep 2017 08:09:28 -0000 ----- Original Message ----- > From: "Eduardo Habkost" > To: "Paolo Bonzini" > Cc: "Eduardo Otubo" , qemu-devel@nongnu.org, qemu-trivial@nongnu.org, "Michael Tokarev" > , "Markus Armbruster" , "Alexander Graf" > Sent: Saturday, September 16, 2017 12:21:13 AM > Subject: Re: [PATCH] dma/i82374: avoid double creation of i82374 device > > On Fri, Sep 15, 2017 at 12:18:11PM +0200, Paolo Bonzini wrote: > > On 15/09/2017 11:06, Eduardo Otubo wrote: > > > QEMU fails when used with the following command line: > > > > > > ./ppc64-softmmu/qemu-system-ppc64 -S -machine 40p,accel=tcg -device > > > i82374 > > > qemu-system-ppc64: hw/isa/isa-bus.c:110: isa_bus_dma: Assertion > > > `!bus->dma[0] && !bus->dma[1]' failed. > > > Aborted (core dumped) > > > > > > The 40p machine type already creates the device i82374. If specified in > > > the > > > command line, it will try to create it again, hence generating the error. > > > The > > > function isa_bus_dma() isn't supposed to be called twice for the same > > > bus. One > > > way to avoid this problem is to set user_creatable=false. > > > > > > A possible fix in a near future would be making > > > isa_bus_dma()/DMA_init()/i82374_realize() return an error instead of > > > asserting > > > as well. > > > > > > Signed-off-by: Eduardo Otubo > > > --- > > > hw/dma/i82374.c | 5 +++++ > > > 1 file changed, 5 insertions(+) > > > > > > diff --git a/hw/dma/i82374.c b/hw/dma/i82374.c > > > index 6c0f975df0..e76dea8dc7 100644 > > > --- a/hw/dma/i82374.c > > > +++ b/hw/dma/i82374.c > > > @@ -139,6 +139,11 @@ static void i82374_class_init(ObjectClass *klass, > > > void *data) > > > dc->realize = i82374_realize; > > > dc->vmsd = &vmstate_i82374; > > > dc->props = i82374_properties; > > > + dc->user_creatable = false; > > > + /* > > > + * Reason: i82374_realize() crashes (assertion failure inside > > > isa_bus_dma() > > > + * if the device is instantiated twice. > > > + */ > > > } > > > > > > static const TypeInfo i82374_info = { > > > > > > > This breaks "make check", doesn't it? > > Why would it? I don't see any test code using -device i82374. > (endianness-test uses -device i82378). You're right, both Aurelien and I were confused. If you want to accept this patch it would be fine then, even if giving an error may be preferrable. Paolo