ChangeLog/4.0

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Revision as of 12:47, 14 March 2019 by Berto (talk | contribs) (New QMP command: x-blockdev-reopen)

System emulation

Incompatible changes

  • The "handle" option to -fsdev and -virtfs has been removed. The "local" or "proxy" options should be used instead.
  • The "-virtioconsole" option has been removed. Use "-device virtconsole" instead.
  • The "-no-frame" option has been removed. It was only usable with SDL1.2, and support for this library has been suspended now.
  • The "-enable-hax" option has been removed. Use "-accel hax" instead.
  • The legacy "ivshmem" device has been removed. Use "ivshmem-doorbell" or "ivshmem-plain" instead.
  • The x86 machine types "pc-0.10" and "pc-0.11" have been removed. Use a newer machine type instead.
  • The "irq" property of the "spapr-vscsi", "spapr-vlan" and "spapr-vty" devices has been removed with no replacement.
  • The "memory-backend-memfd" backend object type will be reported as unavailable on hosts systems without memfd sealing support. On previous versions, "memory-backend-memfd" was reported as available, but didn't work properly without sealing support.

New deprecated options and features

  • cpu-add QMP/HMP command
  • machine-types pc-0.12, pc-0.13, pc-0.14 and pc-0.15
  • qemu-nbd --partition=N option

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

Alpha

Arm

  • Implement the ARMv8.0-SB extension
  • Implement the ARMv8.0-PredInv extension
  • Implement the ARMv8.1-HPD extension
  • Implement the ARMv8.1-LOR extension (as the trivial "no limited ordering regions provided" minimum)
  • Implement the ARMv8.2-FHM extension
  • Implement the ARMv8.2-AA32HPD extension
  • Implement the ARMv8.3-PAuth extension
  • Implement the ARMv8.3-JSConv extension
  • Implement the ARMv8.4-CondM extension
  • Implement the ARMv8.5-CondM extension
  • Implement the ARMv8.5-FRINT extension
  • Implement the Armv8.5-BTI extension for system emulation mode
  • New machines "musca-a" and "musca-b1" -- these model the Arm "Musca" development boards
  • New machine "mps2-an521" -- this is a model of the AN521 FPGA image for the MPS2 devboard
  • Support TBI (top-byte-ignore) properly for linux-user mode
  • The micro:bit board now boots simple MicroPython programs since device emulation for the timer, GPIO, NVMC and RNG has been added
  • The cubieboard model now implements the 'A' SRAM
  • AArch64 processors can now boot from a kernel placed over 4GB into RAM
  • The stellaris boards ("lm3s6965evb", "lm3s811evb") now implement the watchdog timer device
  • The BLK_MAX register in the TZ MPC device now reports the correct value
  • The u-boot "noload" image type is now supported for the Arm virt board
  • The Arm virt board now permits more than 255GB of RAM
  • stm32f2xx_usart: Do not update data register when device is disabled
  • virt board ACPI tables: COHACC override flag now correctly set in IORT SMMUv3 node
  • AArch32 exception return is fixed to permit a switch from Mon->Hyp mode
  • ftgmac100: implement the new MDIO interface on Aspeed SoC
  • Emulation of the ARM PMU has been improved
  • Fix various places where we failed to UNDEF invalid A64 instructions
  • Don't UNDEF a valid FCMLA on 32-bit inputs
  • Make FPSCR/FPCR trapped-exception bits RAZ/WI
  • Fixed a bug in handling clearing of FPSCR/FPSR exception status bits
  • armv7m_nvic: Allow byte accesses to SHPR1 register
  • linux-user: support HWCAP_CPUID which exposes ID registers to user code
  • Fixed a bug where the v8M MPU was always using the background region if it was enabled, rather than only if there was no hit on a more specific region

HPPA

  • Fix condition code generation for "add,<" & "add,<=".
  • Fix the output for "dcor".
  • Fix pci config address access.
  • Map CPU HPA regions into PCI address space.

M68k

  • The "mcf5208evb" machine now supports loading of firmware binaries with the "-bios" option.

Microblaze

MIPS

  • Added support for I7200 CPU (nanoMIPS32 ISA + DSP ASE; system mode only).
  • Added support for I6500 CPU (MIPS64R6 ISA + MSA ASE + multicore features).
  • Added support for QMP-based querying of the available CPU types.
  • Added support for SAARI and SAAR configuration registers.
  • Added support for MTTCG (multi-threaded TCG).
  • Improved support for ITU (Interthread Communication Unit).
  • Improved support for Fulong 2E machine.
  • Improved end user documentation.
  • Fixed build for MIPS n32 hosts.

Nios2

OpenRISC

PowerPC

  • POWER9 large decrementer is now supported (pseries & powernv machines, TCG & KVM)
  • sam460ex can now have 2GB memory
  • pseries default CPU type is now POWER9
  • pseries now supports the XIVE interrupt controller of POWER9 (emulated version only)
  • pseries can now select its interrupt controller through a new ic-mode machine option
  • pseries can now control the exposure of the host model and system-id through the new host-model and host-serial machine options
  • pseries now supports "-vga cirrus"
  • pseries now supports hot plug and unplug of PCI Host Bridges (PHBs)
  • pseries now enables Spectre/Meltdown mitigations by default (this will cause warnings with TCG which doesn't have the mitigations implemented)
  • pseries now supports the proposed count-cache-flush mitigation for Spectre (this requires guest co-operation, but should be lower cost than the current approaches)
  • powernv now supports POWER9 cpus
  • powernv now allows kernel images up to 256MiB
  • gdbstub can now access SPRs
  • mac99 machine now defaults to sungem NIC instead of ne2k_pci
  • e500 now has a device for its I2C controller
  • e500 has had an update to a newer U-Boot version
  • ref405, sam460ex and taihu now have flash memory of fixed size matching the physical hardware instead of deriving it from -drive if-pflash

RISC-V

  • The virt board now supports PCI and USB.
  • The FS field of mstatus now supports three states (dirty, clean, and off).
  • The TSR, TW, and TVM fields of mstatus are now implemented.
  • The misa CSR is now writable.

s390

CPU models

  • The 'zpci' feature bit is now indicated by default in the 'qemu' cpu model.
  • The z14 cpu model now includes the multiple epoch and PTFF enhancement features per default.
  • A cpu model for the z14 GA 2 has been added.

Devices

  • vfio-ap now no longer inhibits usage of memory ballooners.
  • zPCI devices now provide some instruction counters to the guest (for a Linux guest, check /sys/kernel/debug/pci/<function>/statistics).
  • zPCI devices are now explicitly marked as unmigratable. No change in functionality, migration support for zPCI devices had never been implemented.
  • vfio-ap now supports hot(un)plug of the vfio-ap device.

TCG

  • Support for the floating-point extension facility has been added.
  • Code for vector support instructions has been added.

SH

  • Machine r2d's flash memory size doubled to 16MiB to match physical hardware.

SPARC

  • Fix Solaris boot on SS-10/SS-20 machines with OpenBIOS (OpenBIOS)

TileGX

Tricore

  • Fixed mixed up operands in CADDN and CADD

x86

  • The HAX accelerator is now supported for POSIX hosts other than Darwin, including Linux and NetBSD.
  • Machines pc-* now support configuring firmware with -machine pflash0=ID0,pflash1=ID1 in addition to -drive if=pflash,... This permits use of -blockdev.

Xtensa

  • xtfpga boards provide SMP support expected by linux (interrupt distributor, IPI and runstall)
  • New test_mmuhifi_c3 core configuration capable of running SMP linux
  • Flexible length instructions extension (FLIX) is now supported

Device emulation and assignment

ACPI

Audio

Block devices

  • IDE/via: Implement PCI IDE mode
  • virtio-blk: DISCARD and WRITE_ZEROES support

Graphics

Input devices

I2C

  • smbus_eeprom: Will now transfer its state
  • pm_smbus: I2C block transfers will now work properly
  • pm_smbus: state transfer will now work properly

IPMI

Network devices

  • pvrdma: Add support for RDMA MAD
  • pvrdma: Removed the dev-caps-max-sge parameter

NVDIMM

PCI/PCIe

  • Generic PCIe root port link speed and width enhancements: Starting with the Q35 QEMU 4.0 machine type, generic pcie-root-port will default to the maximum PCIe link speed (16GT/s) and width (x32) provided by the PCIe 4.0 specification. Experimental options x-speed= and x-width= are provided for custom tuning, but it is expected that the default over-provisioning of bandwidth is optimal for the vast majority of use cases. Previous machine versions and ioh3420 root ports will continue to default to 2.5GT/x1 links.

SCSI

SMBIOS

TPM

  • ACPI HID for TPM TIS for TPM 2.0 has been corrected to MSFT0101; this should allow all Operating Systems to use the TPM 2.0 through the TIS interface
  • QEMU support for TPM PPI (Physical Presence Interface) allows OS to use PPI functionality if the firmware supports it

USB

VFIO

  • EDID interface for supported mdevs (Intel vGPU, host kernel v5.0+). Use options xres= and yres= to specify display resolution.

virtio

Xen

fw_cfg

9pfs

Audio

Character devices

  • The "wait" option for the socket backend is now forbidden for client sockets. It previously had no functional effect except for server sockets.
  • The "reconnect" option for the socket backend is now forbidden for server sockets. It previously had no functional effect except for client sockets.

Crypto subsystem

  • The block storage encryption backends are now capable of using multiple threads for encryption/decryption

GUI

  • Add -display spice-app: configure & launch a Spice client. With upcoming virt-viewer 8.0, this will present a UI similar to QEMU GTK (with monitor & console etc), but running in a separate process.
  • Support for building against SDL1.2 has been deleted. SDL2 should be used instead.
  • The VNC server will no longer accidentally delete its UNIX listener socket when clients disconnect
  • The VNC server supports two new options "tls-authz" and "sasl-authz". These provide the ID of a previously create "authz" object to be used for authorization checks on incoming client identities.
  • The VNC server "acl" option has been deprecated in favour of "tls-authz" and "sasl-authz"

Host support

Memory backends

Monitor

  • QMP can now execute a few commands "out of band". This is useful for postcopy recovery. For details, see docs/interop/qmp-spec.txt.
  • query-qmp-schema reflects QEMU's build configuration more closely. For instance, stuff related to replication is properly absent when QEMU was built with --disable-replication, and stuff specific to other targets is properly absent.
  • QMP events SHUTDOWN and RESET now carry a reason
  • New QMP command query-current-machine
  • QMP/HMP command system_wakeup now fails when the guest isn't suspended, or doesn't even support suspend.
  • QMP/HMP command cpu-add is now deprecated
  • New QMP commands block-dirty-bitmap-enable, block-dirty-bitmap-disable, and block-dirty-bitmap-merge, plus enhancements to transaction, nbd-server-add, query-block, and block-dirty-bitmap-add, allow a management application to perform incremental backups with an NBD client as a consumer learning which portions of the disk were changed while the bitmap was enabled. The experimental commands x-block-dirty-bitmap-enable, x-block-dirty-bitmap-disable, x-block-dirty-bitmap-merge and x-nbd-server-add-bitmap were removed in favor of the stable commands.
  • The HMP commands acl_show, acl_reset, acl_policy, acl_add, acl_remove are deprecated with no direct replacement. The new authorization framework provides an alternative object based approach to the authorization / access control problem, with pluggable implementations.
  • New experimental QMP command x-blockdev-reopen that allows reopening any block device in use with a new set of options.

Migration

  • free page hinting through virtio-balloon to avoid migrating unused pages
  • ignore-shared feature for skipping shared memory blocks for migration-on-same-host hacks

Network

  • new QMP/HMP command announce_self to trigger generation of broadcast RARP frames to update network switches.

Block devices and tools

  • Improved tracing and error diagnostics for NBD code
  • Fix infinite loop in DMG image format
  • A new qemu-nbd --bitmap option allows the exposure of a persistent dirty bitmap for a qcow2 image not in use by a guest, in a simpler manner than the older procedure of using QMP commands to a temporary qemu process attached to the file.
  • A new qemu-nbd --list option enables the ability to probe a remote NBD server for information about what it is exporting.
  • The qemu-nbd --partition=N option has been deprecated; it does not support GPT partitions, and has always been broken for MBR logical partition 6 and beyond. Its functionality of exporting a subset of the guest-visible data can still be accomplished with --image-opts driver=raw,offset=X,size=Y.
  • qemu-img info now displays information about persistent bitmaps stored in qcow2 files.
  • The size of qcow2 L2 cache entries is reduced by default to make better use of the memory and increase the I/O performance.
  • A new qemu-nbd --tls-authz command line argument and counterpart tls-authz argument to QMP nbd-server-start permit an NBD server to fine-tune which clients may connect to a TLS session.

Tracing

  • The new qemu-trace-stap script makes it convenient to collect traces without writing SystemTap scripts. See "man qemu-trace-stap" for details.

Miscellaneous

  • QEMU's builtin gdbstub now supports the gdb multiprocess extension. Boards which have more than one cluster of CPUs (like the 'xlnx-zcu102' board when run with '-smp 6') will report them as being two processes (each of which has one thread per CPU in the cluster). You will need at least GDB 7.2. Attach to QEMU with a GDB command sequence like:
target extended :1234
add-inferior
inferior 2
attach 2
and then the "info threads" command should show 2 processes.
  • QEMU will default to KVM when compiled with --disable-tcg or when launched from an executable whose name ends with "kvm".
  • Common Python code now lives under "python", instead of under "scripts". That directory now contains a proper "qemu" Python module. qmp Python libraries, previously under "scripts/qmp" have also moved to the same location.
  • The curses front-end now allows to type non-ascii letters. Emulating pressing escape now takes 25ms instead of 1s.
  • The curses front-end now supports printing all non-ascii letters. The VGA font encoding can now be set with e.g. "-display curses,charset=CP850" . The default charset is CP437 (default VGA font).

User-mode emulation

  • The docker.py script now checks the path and persistence status of binfmt_misc entries when installing and updating user-mode docker containers

TCG

Guest agent

Build Information

CI

GIT submodules

Build Dependencies

  • QEMU now requires at least GCC version 4.8 or Clang version 3.4 (equivalent to Clang from Xcode 5.1 on macOS) to be built
  • Running the QEMU testsuite now requires the Perl Test::Harness module. Most Linux and BSD distributions however install it by default together with Perl.
  • For OSX hosts, our minimum supported version is now OSX 10.10. We have fixed the bug which meant that some guests would crash when running with the Cocoa UI on OSX 10.14 Mojave.
  • We now have some documentation in rST format which we process with Sphinx. The host system must now have the 'build-sphinx' program available (version 1.3 or better) in order for any of the documentation to be built.

Known issues