From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54651) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UoUH8-0002RX-6g for qemu-devel@nongnu.org; Mon, 17 Jun 2013 03:54:56 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UoUH5-0000FO-Ur for qemu-devel@nongnu.org; Mon, 17 Jun 2013 03:54:54 -0400 Received: from mx1.redhat.com ([209.132.183.28]:12725) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UoUH5-0000F1-NA for qemu-devel@nongnu.org; Mon, 17 Jun 2013 03:54:51 -0400 Message-ID: <51BEC148.50009@redhat.com> Date: Mon, 17 Jun 2013 09:56:56 +0200 From: Laszlo Ersek MIME-Version: 1.0 References: <1371416189-29563-1-git-send-email-mst@redhat.com> In-Reply-To: <1371416189-29563-1-git-send-email-mst@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 1/2] pvpanic: initialization cleanup List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: Hu Tao , Anthony Liguori , qemu-devel@nongnu.org, Markus Armbruster On 06/16/13 22:59, Michael S. Tsirkin wrote: > Avoid use of static variables: PC systems initialize pvpanic device > through pvpanic_init, so we can simply create the fw_cfg file at that > point. Others don't use fw_cfg at all. This also makes it possible to > assert if fw_cfg is not there rather than skipping the device silently. > > Signed-off-by: Michael S. Tsirkin > --- > hw/misc/pvpanic.c | 23 ++++++++++------------- > 1 file changed, 10 insertions(+), 13 deletions(-) > > diff --git a/hw/misc/pvpanic.c b/hw/misc/pvpanic.c > index 060099b..9ed9897 100644 > --- a/hw/misc/pvpanic.c > +++ b/hw/misc/pvpanic.c > @@ -97,25 +97,22 @@ static void pvpanic_isa_realizefn(DeviceState *dev, Error **errp) > { > ISADevice *d = ISA_DEVICE(dev); > PVPanicState *s = ISA_PVPANIC_DEVICE(dev); > - static bool port_configured; > - FWCfgState *fw_cfg; > > isa_register_ioport(d, &s->io, s->ioport); > - > - if (!port_configured) { > - fw_cfg = fw_cfg_find(); > - if (fw_cfg) { > - fw_cfg_add_file(fw_cfg, "etc/pvpanic-port", > - g_memdup(&s->ioport, sizeof(s->ioport)), > - sizeof(s->ioport)); > - port_configured = true; > - } > - } > } > > int pvpanic_init(ISABus *bus) > { > - isa_create_simple(bus, TYPE_ISA_PVPANIC_DEVICE); > + ISADevice *dev = isa_create_simple(bus, TYPE_ISA_PVPANIC_DEVICE); > + PVPanicState *s = ISA_PVPANIC_DEVICE(dev); > + FWCfgState *fw_cfg = fw_cfg_find(); > + > + assert(fw_cfg); Won't the assert fire if: xen_enabled() && machine != "pc-0.10" && machine != "pc-0.11" && machine != "pc-0.12" && machine != "pc-0.13" && machine != "pc-q35-1.4" Because under the above condition "has_pvpanic" remains "true", but fw_cfg is not initialized. (pc_init_pci_no_kvmclock() in "hw/i386/pc_piix.c" sets "has_pvpanic" to "false", and claims to be "reused by xenfv", so the above condition may be constant false.) > + > + fw_cfg_add_file(fw_cfg, "etc/pvpanic-port", > + g_memdup(&s->ioport, sizeof(s->ioport)), > + sizeof(s->ioport)); > + > return 0; > } > > Series looks good to me otherwise. Thanks Laszlo