I've confirmed this works correctly with the latest git. If you can reproduce it with the latest bits, please reopen a new bug report with details.
I've tested: commit d9b73e47a3d596c5b33802597ec5bd91ef3348e2 Author: Corentin Chary <corenti...@iksaif.net> Date: Tue Jun 1 23:05:44 2010 +0200 vnc: add missing target for vnc-encodings-*.o -- pci_del fails to remove PCI virtio storage device https://bugs.launchpad.net/bugs/544367 You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. Status in QEMU: New Bug description: In qemu monitor, command pci_del silently fails to remove a virtio storage device previously added with pci_add. It doesn't matter whether the guest actually makes use of the virtio device for this failure to happen. = QEMU command line = /usr/local/bin/qemu-system-x86_64 -S -snapshot -enable-kvm -smp 1 -cdrom /pub/gentoo/releases/x86/10.1/livedvd-x86-amd64-32ul-10.1.iso -boot order=d -m 512 -usb -name gentoo_livedvd -ctrl-grab -vga cirrus -chardev pty,id=serial0 -device isa-serial,chardev=serial0 -chardev socket,id=monitor,path=/tmp/gentoo_livedvd.monitor,server,nowait -mon chardev=monitor,mode=readline = Host information = Distribution: Gentoo Linux Portage 2.1.7.16 (default/linux/x86/10.0, gcc-4.3.4, glibc-2.10.1-r1, 2.6.31-gentoo-r6 i686) System uname: linux-2.6.31-gentoo-r6-i686-genuine_intel-r-_cpu_t13...@_1.66ghz-with-gentoo-1.12.13 = Guest information = Gentoo Linux 10.1 x86 LiveDVD