From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49849) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cu4HE-0004Qg-7X for qemu-devel@nongnu.org; Fri, 31 Mar 2017 17:40:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cu4HB-0002uE-5C for qemu-devel@nongnu.org; Fri, 31 Mar 2017 17:40:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41702) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cu4HA-0002qn-Vh for qemu-devel@nongnu.org; Fri, 31 Mar 2017 17:40:09 -0400 Date: Sat, 1 Apr 2017 00:40:00 +0300 From: "Michael S. Tsirkin" Message-ID: <20170401003951-mutt-send-email-mst@kernel.org> References: <20170331044711.21749-1-aik@ozlabs.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170331044711.21749-1-aik@ozlabs.ru> Subject: Re: [Qemu-devel] [PATCH qemu] pci: Only unmap bus_master_enabled_region if was added previously List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexey Kardashevskiy Cc: qemu-devel@nongnu.org, Marcel Apfelbaum , John Snow , Max Reitz , Paolo Bonzini On Fri, Mar 31, 2017 at 03:47:11PM +1100, Alexey Kardashevskiy wrote: > Normally pci_init_bus_master() would be called either via > bus->machine_done.notify or directly from do_pci_register_device(). > > However if a device's realize() failed, pci_init_bus_master() is not > called, and do_pci_unregister_device() fails on > memory_region_del_subregion() as it was not mapped. > > This adds a check that subregion was mapped before unmapping it. > > Fixes: c53598ed18e4 ("pci: Add missing drop of bus master AS reference") > Signed-off-by: Alexey Kardashevskiy Applied, thanks everyone. > --- > This is to pass iotest 051 which does run QEMU like this: > > ppc64-softmmu/qemu-system-ppc64 -nodefaults -machine accel=qtest -nographic -monitor stdio -serial none -drive if=virtio > > which normally fails with: > > qemu-system-ppc64: -drive if=virtio: Device needs media, but drive is empty > > or asserts (without this patch): > > qemu-system-ppc64: /home/aik/p/qemu-kvm/memory.c:2118: memory_region_del_subregion: Assertion `subregion->container == mr' failed. > --- > hw/pci/pci.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/hw/pci/pci.c b/hw/pci/pci.c > index bd8043c460..259483b1c0 100644 > --- a/hw/pci/pci.c > +++ b/hw/pci/pci.c > @@ -869,8 +869,10 @@ static void do_pci_unregister_device(PCIDevice *pci_dev) > pci_dev->bus->devices[pci_dev->devfn] = NULL; > pci_config_free(pci_dev); > > - memory_region_del_subregion(&pci_dev->bus_master_container_region, > - &pci_dev->bus_master_enable_region); > + if (memory_region_is_mapped(&pci_dev->bus_master_enable_region)) { > + memory_region_del_subregion(&pci_dev->bus_master_container_region, > + &pci_dev->bus_master_enable_region); > + } > address_space_destroy(&pci_dev->bus_master_as); > } > > -- > 2.11.0