ChangeLog/5.0

From QEMU

System emulation

Incompatible changes

  • The bluetooth code has been removed without replacement. It was quite neglected over the years and likely not usable anymore. You can passthrough a dedicated USB bluetooth dongle to guests on most machines instead if you still need bluetooth in your guest.
  • The -virtfs_synth option has been removed. You can use -fsdev synth together with -device virtio-9p-... instead.
  • The pc-0.12, pc-0.13, pc-0.14, pc-0.15 machines have been removed.
  • The "-accel" and "-machine accel=" options are now incompatible with each other.
  • The "-tb-size N" option has been replaced by "-accel tcg,tb-size=N".

New deprecated options and features

Consult the "Deprecated Features" appendix for the full list of historically deprecated features/options.

Alpha

68k

Arm

  • The Cortex-M7 CPU is now supported
  • New board: tacoma-bmc
  • QEMU now correctly implements trapping of more EL1 system register accesses to EL2 (eg HCR_EL2 TID1, TID2 bits, HSTR_EL2)
  • The no-op system registers required for a "trivial Jazelle" implementation have been added
  • The DC CVAP and DC CVADP instructions are now supported

HPPA

Microblaze

MIPS

Nios2

OpenRISC

PowerPC

  • pseries machine type
    • No longer require a reconfiguration reboot for a guest selecting XIVE interrupt controller when ic-mode=dual
    • Now consumes less host resources when running a KVM guest with XIVE (with a recent enough host kernel). This allows running more concurrent guests with KVM accelerated XIVE.
  • powernv machine type
    • Numerous improvements to the model
    • Can now run KVM guests under a TCG emulated powernv machine
    • Basic POWER10 support

RISC-V

s390

SH

SPARC

TileGX

Tricore

x86

Xtensa

Device emulation and assignment

ACPI

Audio

Block devices

Graphics

Input devices

IPMI

Network devices

NVDIMM

PCI/PCIe

SCSI

SMBIOS

TPM

USB

VFIO

virtio

Xen

fw_cfg

9pfs

Semihosting

Audio

Character devices

Crypto subsystem

GUI

Host support

Memory backends

Monitor

QMP

Migration

Network

Block device backends and tools

Tracing

Miscellaneous

  • It is now possible to specify multiple "-accel" options. The first available accelerator will be used.
  • KVM and Xen-specific machine options have been moved to "-accel"; the previous way to set the option is still available for backwards-compatibility. The options that were moved are:
    • "-machine kernel_irqchip=" (now "-accel kvm,kernel-irqchip=")
    • "-machine kvm_shadow_mem=" (now "-accel kvm,kvm-shadow-mem=")
    • "-machine igd-passthru=" (now "-accel xen,igd-passthrough=")

User-mode emulation

TCG

Guest agent

  • The 'set-guest-time' command is now fenced off on systems that do not have the 'hwclock' command available (e.g. on s390x).

Build Information

Python

GIT submodules

Container Based Builds

Build Dependencies

Testing

Windows

Known issues