Note: This RFC has been sent to netdev as well as qemu-devel lists

This patchset implements XDP offload feature in qemu. The successful
operation of this feature depends on availability of XDP offload
feature in guest, qemu and host. When this feature isn't available in
qemu or host, the request from guest to offload an XDP program should
fail.

Patch 1/3 adds support for libbpf in configure script.
Patch 2/2 enables offloading of ebpf program.
Patch 3/3 enabled offloading of ebpf map.

Points for improvement (TODO):
- In future virtio can have feature bit for offloading capability

- TUNGETFEATURES should have a flag to notify about offloading
  capability

- Submit virtio spec patch to describe XDP offloading feature

- DoS: Offloaded map uses host's memory which is other than what has
  been allocated for the guest. Offloading many maps of large size can
  be one of the DoS strategy. Hence qemu should have parameter to
  limit how many maps guest can offload or how much memory offloaded
  maps use.

Note:
This set directly modifies virtio_net.h header instead of
importing it from existing kernel headers because relevant changes
aren't present in kernel repository yet. Hence changes to virtio_net.h
are for RFC purpose only.


Jason Wang (2):
  virtio-net: add support for offloading XDP program
  virtio-net: add support for offloading an ebpf map

Prashant Bhole (1):
  configure: add libbpf support

 configure                                   |  23 +++
 hw/net/Makefile.objs                        |   2 +
 hw/net/virtio-net.c                         | 157 ++++++++++++++++++++
 include/net/tap.h                           |   2 +
 include/standard-headers/linux/virtio_net.h |  50 +++++++
 net/Makefile.objs                           |   1 +
 net/tap-bsd.c                               |   5 +
 net/tap-linux.c                             |  48 ++++++
 net/tap-linux.h                             |   1 +
 net/tap-solaris.c                           |   5 +
 net/tap-stub.c                              |   5 +
 net/tap.c                                   |   7 +
 net/tap_int.h                               |   1 +
 13 files changed, 307 insertions(+)

-- 
2.20.1

Patchew URL: https://patchew.org/QEMU/20191126100914.5150-1-prashantbhole.linux@gmail.com/



Hi,

This series failed the docker-quick@centos7 build test. Please find the testing commands and
their output below. If you have Docker installed, you can probably reproduce it
locally.

=== TEST SCRIPT BEGIN ===
#!/bin/bash
make docker-image-centos7 V=1 NETWORK=1
time make docker-test-quick@centos7 SHOW_ENV=1 J=14 NETWORK=1
=== TEST SCRIPT END ===

  CC      ui/input-keymap.o
  CC      ui/input-legacy.o
  CC      ui/kbd-state.o
/tmp/qemu-test/src/net/tap-linux.c:34:21: fatal error: bpf/bpf.h: No such file or directory
 #include <bpf/bpf.h>
                     ^
compilation terminated.
---
  SIGN    pc-bios/optionrom/linuxboot.bin
  SIGN    pc-bios/optionrom/kvmvapic.bin
  BUILD   pc-bios/optionrom/linuxboot_dma.img
make: *** [net/tap-linux.o] Error 1
make: *** Waiting for unfinished jobs....
  BUILD   pc-bios/optionrom/pvh.img
  BUILD   pc-bios/optionrom/linuxboot_dma.raw
---
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['sudo', '-n', 'docker', 'run', '--label', 'com.qemu.instance.uuid=be849bfed02d4ea7b19f7746fe037bd5', '-u', '1001', '--security-opt', 'seccomp=unconfined', '--rm', '-e', 'TARGET_LIST=', '-e', 'EXTRA_CONFIGURE_OPTS=', '-e', 'V=', '-e', 'J=14', '-e', 'DEBUG=', '-e', 'SHOW_ENV=1', '-e', 'CCACHE_DIR=/var/tmp/ccache', '-v', '/home/patchew/.cache/qemu-docker-ccache:/var/tmp/ccache:z', '-v', '/var/tmp/patchew-tester-tmp-3d2z3wl3/src/docker-src.2019-11-26-05.31.05.21708:/var/tmp/qemu:z,ro', 'qemu:centos7', '/var/tmp/qemu/run', 'test-quick']' returned non-zero exit status 2.
filter=--filter=label=com.qemu.instance.uuid=be849bfed02d4ea7b19f7746fe037bd5
make[1]: *** [docker-run] Error 1
make[1]: Leaving directory `/var/tmp/patchew-tester-tmp-3d2z3wl3/src'
make: *** [docker-run-test-quick@centos7] Error 2

real    1m56.447s
user    0m8.519s


The full log is available at
http://patchew.org/logs/20191126100914.5150-1-prashantbhole.linux@gmail.com/testing.docker-quick@centos7/?type=message.
---
Email generated automatically by Patchew [https://patchew.org/].
Please send your feedback to patchew-devel@redhat.com

On 11/26/19 7:33 PM, no-reply@patchew.org wrote:
> Patchew URL: https://patchew.org/QEMU/20191126100914.5150-1-prashantbhole.linux@gmail.com/
> 
> 
> 
> Hi,
> 
> This series failed the docker-quick@centos7 build test. Please find the testing commands and
> their output below. If you have Docker installed, you can probably reproduce it
> locally.
> 
> === TEST SCRIPT BEGIN ===
> #!/bin/bash
> make docker-image-centos7 V=1 NETWORK=1
> time make docker-test-quick@centos7 SHOW_ENV=1 J=14 NETWORK=1
> === TEST SCRIPT END ===
> 
>    CC      ui/input-keymap.o
>    CC      ui/input-legacy.o
>    CC      ui/kbd-state.o
> /tmp/qemu-test/src/net/tap-linux.c:34:21: fatal error: bpf/bpf.h: No such file or directory
>   #include <bpf/bpf.h>

Sorry, I missed to enclose it in #ifdef CONFIG_LIBBPF.
It should be fixed whenever I'll post next revision.


Prashant


>                       ^
> compilation terminated.
> ---
>    SIGN    pc-bios/optionrom/linuxboot.bin
>    SIGN    pc-bios/optionrom/kvmvapic.bin
>    BUILD   pc-bios/optionrom/linuxboot_dma.img
> make: *** [net/tap-linux.o] Error 1
> make: *** Waiting for unfinished jobs....
>    BUILD   pc-bios/optionrom/pvh.img
>    BUILD   pc-bios/optionrom/linuxboot_dma.raw
> ---
>      raise CalledProcessError(retcode, cmd)
> subprocess.CalledProcessError: Command '['sudo', '-n', 'docker', 'run', '--label', 'com.qemu.instance.uuid=be849bfed02d4ea7b19f7746fe037bd5', '-u', '1001', '--security-opt', 'seccomp=unconfined', '--rm', '-e', 'TARGET_LIST=', '-e', 'EXTRA_CONFIGURE_OPTS=', '-e', 'V=', '-e', 'J=14', '-e', 'DEBUG=', '-e', 'SHOW_ENV=1', '-e', 'CCACHE_DIR=/var/tmp/ccache', '-v', '/home/patchew/.cache/qemu-docker-ccache:/var/tmp/ccache:z', '-v', '/var/tmp/patchew-tester-tmp-3d2z3wl3/src/docker-src.2019-11-26-05.31.05.21708:/var/tmp/qemu:z,ro', 'qemu:centos7', '/var/tmp/qemu/run', 'test-quick']' returned non-zero exit status 2.
> filter=--filter=label=com.qemu.instance.uuid=be849bfed02d4ea7b19f7746fe037bd5
> make[1]: *** [docker-run] Error 1
> make[1]: Leaving directory `/var/tmp/patchew-tester-tmp-3d2z3wl3/src'
> make: *** [docker-run-test-quick@centos7] Error 2
> 
> real    1m56.447s
> user    0m8.519s
> 
> 
> The full log is available at
> http://patchew.org/logs/20191126100914.5150-1-prashantbhole.linux@gmail.com/testing.docker-quick@centos7/?type=message.
> ---
> Email generated automatically by Patchew [https://patchew.org/].
> Please send your feedback to patchew-devel@redhat.com
> 

Patchew URL: https://patchew.org/QEMU/20191126100914.5150-1-prashantbhole.linux@gmail.com/



Hi,

This series failed the docker-mingw@fedora build test. Please find the testing commands and
their output below. If you have Docker installed, you can probably reproduce it
locally.

=== TEST SCRIPT BEGIN ===
#! /bin/bash
export ARCH=x86_64
make docker-image-fedora V=1 NETWORK=1
time make docker-test-mingw@fedora J=14 NETWORK=1
=== TEST SCRIPT END ===

  CC      aarch64-softmmu/hw/arm/musicpal.o
  CC      aarch64-softmmu/hw/arm/netduino2.o
  CC      aarch64-softmmu/hw/arm/nseries.o
/tmp/qemu-test/src/hw/net/virtio-net.c:636:12: error: 'peer_attach_ebpf' defined but not used [-Werror=unused-function]
 static int peer_attach_ebpf(VirtIONet *n, int len, void *insns, uint8_t gpl)
            ^~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make[1]: *** [/tmp/qemu-test/src/rules.mak:69: hw/net/virtio-net.o] Error 1
make[1]: *** Waiting for unfinished jobs....
  CC      aarch64-softmmu/hw/arm/omap_sx1.o
  CC      aarch64-softmmu/hw/arm/palm.o
make: *** [Makefile:491: x86_64-softmmu/all] Error 2
make: *** Waiting for unfinished jobs....
  CC      aarch64-softmmu/hw/arm/gumstix.o
  CC      aarch64-softmmu/hw/arm/spitz.o
---
  CC      aarch64-softmmu/gdbstub-xml.o
  CC      aarch64-softmmu/trace/generated-helpers.o
  CC      aarch64-softmmu/target/arm/translate-sve.o
/tmp/qemu-test/src/hw/net/virtio-net.c:636:12: error: 'peer_attach_ebpf' defined but not used [-Werror=unused-function]
 static int peer_attach_ebpf(VirtIONet *n, int len, void *insns, uint8_t gpl)
            ^~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make[1]: *** [/tmp/qemu-test/src/rules.mak:69: hw/net/virtio-net.o] Error 1
make: *** [Makefile:491: aarch64-softmmu/all] Error 2
Traceback (most recent call last):
  File "./tests/docker/docker.py", line 662, in <module>
    sys.exit(main())
---
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['sudo', '-n', 'docker', 'run', '--label', 'com.qemu.instance.uuid=5b6acc2ac7494ad6b59706c9dd26c3cd', '-u', '1001', '--security-opt', 'seccomp=unconfined', '--rm', '-e', 'TARGET_LIST=', '-e', 'EXTRA_CONFIGURE_OPTS=', '-e', 'V=', '-e', 'J=14', '-e', 'DEBUG=', '-e', 'SHOW_ENV=', '-e', 'CCACHE_DIR=/var/tmp/ccache', '-v', '/home/patchew/.cache/qemu-docker-ccache:/var/tmp/ccache:z', '-v', '/var/tmp/patchew-tester-tmp-4e2hnnd5/src/docker-src.2019-11-26-05.33.37.332:/var/tmp/qemu:z,ro', 'qemu:fedora', '/var/tmp/qemu/run', 'test-mingw']' returned non-zero exit status 2.
filter=--filter=label=com.qemu.instance.uuid=5b6acc2ac7494ad6b59706c9dd26c3cd
make[1]: *** [docker-run] Error 1
make[1]: Leaving directory `/var/tmp/patchew-tester-tmp-4e2hnnd5/src'
make: *** [docker-run-test-mingw@fedora] Error 2

real    2m24.967s
user    0m8.999s


The full log is available at
http://patchew.org/logs/20191126100914.5150-1-prashantbhole.linux@gmail.com/testing.docker-mingw@fedora/?type=message.
---
Email generated automatically by Patchew [https://patchew.org/].
Please send your feedback to patchew-devel@redhat.com