On Wed, 23 May 2018 09:38:33 +0200 Auger Eric <eric.au...@redhat.com> wrote:
> Hi, > > On 05/10/2018 07:45 PM, Peter Maydell wrote: > > From: Igor Mammedov <imamm...@redhat.com> > > > > load_dtb() depends on arm_load_kernel() to figure out place > > in RAM where it should be loaded, but it's not required for > > arm_load_kernel() to work. Sometimes it's neccesary for > > devices added with -device/device_add to be enumerated in > > DTB as well, which's lead to [1] and surrounding commits to > > add 2 more machine_done notifiers with non obvious ordering > > to make dynamic sysbus devices initialization happen in > > the right order. > > > > However instead of moving whole arm_load_kernel() in to > > machine_done, it's sufficient to move only load_dtb() into > > virt_machine_done() notifier and remove ArmLoadKernelNotifier/ > > /PlatformBusFDTNotifierParams notifiers, which saves us ~90LOC > > and simplifies code flow quite a bit. > > Later would allow to consolidate DTB generation within one > > function for 'mach-virt' board and make it reentrant so it > > could generate updated DTB in device hotplug secenarios. > > > > While at it rename load_dtb() to arm_load_dtb() since it's > > public now. > > > > Add additional field skip_dtb_autoload to struct arm_boot_info > > to allow manual DTB load later in mach-virt and to avoid touching > > all other boards to explicitly call arm_load_dtb(). > > > > 1) (ac9d32e hw/arm/boot: arm_load_kernel implemented as a machine init > > done notifier) > > I face a regression that looks to be caused by this patch (bisect > session result). Reverting it allows the guest to boot. Otherwise I get: > > in kvm_device_access() at > /home/augere/UPSTREAM/qemu/accel/kvm/kvm-all.c:2164: > 2018-05-22T18:02:17.210175Z qemu-system-aarch64: KVM_SET_DEVICE_ATTR > failed: Group 6 attr 0x000000000000c665: Invalid argument > > It happens when booting with -bios option only (with dt, it boots fine). > > I have not identified the root cause yet. Problem was with broken reset order, thanks for catching it early. Quick fix is posted under title "arm: fix qemu crash on startup with -bios option"