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- 5 participants
- 10 discussions
16 Mar '21
This errored because of the undefined XDG_RUNTIME_DIR or
WAYLAND_DISPLAY. I'd tried to prevent that by disabling -e around
this part, but it turns out I should have disabled -u instead.
---
pkgs/os-specific/linux/spectrum/spectrum-vm/spectrum-vm.in | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/pkgs/os-specific/linux/spectrum/spectrum-vm/spectrum-vm.in b/pkgs/os-specific/linux/spectrum/spectrum-vm/spectrum-vm.in
index 4fa0287a805..8d95c178689 100755
--- a/pkgs/os-specific/linux/spectrum/spectrum-vm/spectrum-vm.in
+++ b/pkgs/os-specific/linux/spectrum/spectrum-vm/spectrum-vm.in
@@ -55,7 +55,7 @@ do
esac
done
-set +e
+set +u
if [ -n "$XDG_RUNTIME_DIR" ]
then
set -- -s "$XDG_RUNTIME_DIR" "$@"
@@ -63,7 +63,7 @@ then
then set -- --wayland-sock "$XDG_RUNTIME_DIR/$WAYLAND_DISPLAY" "$@"
fi
fi
-set -e
+set -u
exec "$crosvm" run \
-p init=/sbin/init \
--
2.27.0
2
4
minimize spectrum-vm kernel
---
pkgs/os-specific/linux/spectrum/linux/vm.nix | 449 +++++++++++++++++++
1 file changed, 449 insertions(+)
diff --git a/pkgs/os-specific/linux/spectrum/linux/vm.nix b/pkgs/os-specific/linux/spectrum/linux/vm.nix
index 9c9ba78b691..c313697eeb2 100644
--- a/pkgs/os-specific/linux/spectrum/linux/vm.nix
+++ b/pkgs/os-specific/linux/spectrum/linux/vm.nix
@@ -4,6 +4,7 @@ with lib.kernel;
linux.override {
structuredExtraConfig = {
+ VIRTIO_CONSOLE = yes;
VIRTIO_PCI = yes;
VIRTIO_BLK = yes;
VIRTIO_WL = yes;
@@ -21,5 +22,453 @@ linux.override {
NET_9P = yes;
NET_9P_VIRTIO = yes;
"9P_FS" = yes;
+
+ ACPI = no;
+ AD525X_DPOT = no;
+ ADIN_PHY = no;
+ AF_KCM = no;
+ ALTERA_STAPL = no;
+ ALTERA_TSE = no;
+ AMD_PHY = no;
+ APDS9802ALS = no;
+ AQUANTIA_PHY = no;
+ AT803X_PHY = no;
+ ATA = no;
+ ATA_OVER_ETH = no;
+ ATM_DRIVERS = no;
+ AX88796B_PHY = no;
+ B53 = no;
+ BCM87XX_PHY = no;
+ BCMA = no;
+ BCM_KONA_USB2_PHY = no;
+ BLK_DEV_DRBD = no;
+ BLK_DEV_FD = no;
+ BLK_DEV_LOOP = no;
+ BLK_DEV_NULL_BLK = no;
+ BLK_DEV_RBD = no;
+ BROADCOM_PHY = no;
+ BT = no;
+ C2PORT = no;
+ CAIF = no;
+ CAN = no;
+ CDROM_PKTCDVD = no;
+ CHROME_PLATFORMS = no;
+ CICADA_PHY = no;
+ CMA = no;
+ COMEDI = no;
+ CORTINA_PHY = no;
+ COUNTER = no;
+ DAVICOM_PHY = no;
+ DEV_DAX = no;
+ DMADEVICES = no;
+ DNET = no;
+ DP83822_PHY = no;
+ DP83848_PHY = no;
+ DP83867_PHY = no;
+ DP83TC811_PHY = no;
+ DRM_ETNAVIV = no;
+ DRM_PANEL_ORIENTATION_QUIRKS = module;
+ DS1682 = no;
+ DUMMY_IRQ = no;
+ ECHO = no;
+ ENCLOSURE_SERVICES = no;
+ ETHOC = no;
+ EXT2_FS = no;
+ EXT4_USE_FOR_EXT2 = yes;
+ EXTCON = no;
+ FIELDBUS_DEV = no;
+ FPGA = no;
+ FW_LOADER_USER_HELPER = no;
+ GENERIC_PHY = no;
+ GNSS = no;
+ GREYBUS = no;
+ GS_FPGABOOT = no;
+ HAMRADIO = no;
+ HMC6352 = no;
+ HSI = no;
+ HVC_XEN = no;
+ HW_RANDOM_TIMERIOMEM = no;
+ HW_RANDOM_VIA = no;
+ I2C_ALGOPCF = no;
+ I2C_CHARDEV = no;
+ I2C_COMPAT = no;
+ I2C_HELPER_AUTO = no;
+ I2C_SLAVE_EEPROM = no;
+ I2C_STUB = no;
+ I3C = no;
+ I8K = no;
+ ICPLUS_PHY = no;
+ ICS932S401 = no;
+ IEEE802154_DRIVERS = no;
+ IIO = no;
+ INFINIBAND = no;
+ INPUT_JOYSTICK = no;
+ INPUT_KEYBOARD = no;
+ INPUT_MISC = no;
+ INPUT_MOUSE = no;
+ INPUT_TABLET = no;
+ INPUT_TOUCHSCREEN = no;
+ INTEL_TH = no;
+ INTEL_XWAY_PHY = no;
+ INTERCONNECT = no;
+ IOMMU_IOVA = module;
+ IOSF_MBI = module;
+ IPACK_BUS = no;
+ IPMB_DEVICE_INTERFACE = no;
+ IPMI_HANDLER = no;
+ ISL29003 = no;
+ ISL29020 = no;
+ LEDS_APU = no;
+ LEDS_BD2802 = no;
+ LEDS_BLINKM = no;
+ LEDS_CLASS_FLASH = no;
+ LEDS_CLEVO_MAIL = no;
+ LEDS_GPIO = no;
+ LEDS_LM3530 = no;
+ LEDS_LM3532 = no;
+ LEDS_LM3533 = no;
+ LEDS_LM355x = no;
+ LEDS_LM3642 = no;
+ LEDS_LP3944 = no;
+ LEDS_LP3952 = no;
+ LEDS_LP5521 = no;
+ LEDS_LP5523 = no;
+ LEDS_LP5562 = no;
+ LEDS_LP8501 = no;
+ LEDS_MC13783 = no;
+ LEDS_MENF21BMC = no;
+ LEDS_MLXCPLD = no;
+ LEDS_MLXREG = no;
+ LEDS_MT6323 = no;
+ LEDS_PCA9532 = no;
+ LEDS_PCA955X = no;
+ LEDS_PCA963X = no;
+ LEDS_REGULATOR = no;
+ LEDS_TCA6507 = no;
+ LEDS_TI_LMU_COMMON = no;
+ LEDS_TLC591XX = no;
+ LEDS_TRIGGER_ACTIVITY = no;
+ LEDS_TRIGGER_BACKLIGHT = no;
+ LEDS_TRIGGER_CAMERA = no;
+ LEDS_TRIGGER_DEFAULT_ON = no;
+ LEDS_TRIGGER_GPIO = no;
+ LEDS_TRIGGER_HEARTBEAT = no;
+ LEDS_TRIGGER_NETDEV = no;
+ LEDS_TRIGGER_ONESHOT = no;
+ LEDS_TRIGGER_PATTERN = no;
+ LEDS_TRIGGER_TIMER = no;
+ LEDS_TRIGGER_TRANSIENT = no;
+ LEDS_USER = no;
+ LSI_ET1011C_PHY = no;
+ LXT_PHY = no;
+ MACINTOSH_DRIVERS = no;
+ MAILBOX = no;
+ MARVELL_10G_PHY = no;
+ MARVELL_PHY = no;
+ MCB = no;
+ MDIO_BITBANG = no;
+ MDIO_MSCC_MIIM = no;
+ MEDIA_SUPPORT = no;
+ MEMSTICK = no;
+ MFD_CROS_EC = no;
+ MICREL_PHY = no;
+ MICROCHIP_PHY = no;
+ MICROCHIP_T1_PHY = no;
+ MICROSEMI_PHY = no;
+ MMC = no;
+ MOST = no;
+ MTD = no;
+ MWAVE = no;
+ NATIONAL_PHY = no;
+ NET_DSA_BCM_SF2 = no;
+ NET_DSA_LANTIQ_GSWIP = no;
+ NET_DSA_LOOP = no;
+ NET_DSA_MICROCHIP_KSZ8795 = no;
+ NET_DSA_MICROCHIP_KSZ9477 = no;
+ NET_DSA_MT7530 = no;
+ NET_DSA_MV88E6060 = no;
+ NET_DSA_MV88E6XXX = no;
+ NET_DSA_QCA8K = no;
+ NET_DSA_REALTEK_SMI = no;
+ NET_DSA_SMSC_LAN9303_I2C = no;
+ NET_DSA_SMSC_LAN9303_MDIO = no;
+ NET_VENDOR_ALACRITECH = no;
+ NET_VENDOR_AMAZON = no;
+ NET_VENDOR_AQUANTIA = no;
+ NET_VENDOR_ARC = no;
+ NET_VENDOR_AURORA = no;
+ NET_VENDOR_CADENCE = no;
+ NET_VENDOR_CAVIUM = no;
+ NET_VENDOR_CORTINA = no;
+ NET_VENDOR_EZCHIP = no;
+ NET_VENDOR_GOOGLE = no;
+ NET_VENDOR_HUAWEI = no;
+ NET_VENDOR_INTEL = no;
+ NET_VENDOR_MARVELL = no;
+ NET_VENDOR_MELLANOX = no;
+ NET_VENDOR_MICREL = no;
+ NET_VENDOR_MICROCHIP = no;
+ NET_VENDOR_MICROSEMI = no;
+ NET_VENDOR_NATSEMI = no;
+ NET_VENDOR_NETRONOME = no;
+ NET_VENDOR_NI = no;
+ NET_VENDOR_PENSANDO = no;
+ NET_VENDOR_QUALCOMM = no;
+ NET_VENDOR_RENESAS = no;
+ NET_VENDOR_ROCKER = no;
+ NET_VENDOR_SAMSUNG = no;
+ NET_VENDOR_SEEQ = no;
+ NET_VENDOR_SOCIONEXT = no;
+ NET_VENDOR_SOLARFLARE = no;
+ NET_VENDOR_STMICRO = no;
+ NET_VENDOR_SYNOPSYS = no;
+ NET_VENDOR_VIA = no;
+ NET_VENDOR_WIZNET = no;
+ NET_VENDOR_XILINX = no;
+ NFC = no;
+ NULL_TTY = no;
+ NVME_FC = no;
+ NVME_TARGET = no;
+ N_GSM = no;
+ PARPORT = no;
+ PCCARD = no;
+ PHY_PXA_28NM_HSIC = no;
+ PHY_PXA_28NM_USB2 = no;
+ PMBUS = no;
+ PM_DEBUG = no;
+ QSEMI_PHY = no;
+ RAVE_SP_EEPROM = no;
+ RC_CORE = no;
+ RD_BZIP2 = no;
+ RD_LZ4 = no;
+ RD_LZMA = no;
+ RD_LZO = no;
+ RD_XZ = no;
+ RENESAS_PHY = no;
+ RESET_CONTROLLER = no;
+ RFKILL = no;
+ RMI4_I2C = no;
+ RMI4_SMB = no;
+ ROCKCHIP_PHY = no;
+ RTC_DRV_88PM80X = no;
+ RTC_DRV_ABB5ZES3 = no;
+ RTC_DRV_ABEOZ9 = no;
+ RTC_DRV_ABX80X = no;
+ RTC_DRV_BQ32K = no;
+ RTC_DRV_BQ4802 = no;
+ RTC_DRV_CMOS = no;
+ RTC_DRV_DA9063 = no;
+ RTC_DRV_DS1286 = no;
+ RTC_DRV_DS1307 = no;
+ RTC_DRV_DS1374 = no;
+ RTC_DRV_DS1511 = no;
+ RTC_DRV_DS1553 = no;
+ RTC_DRV_DS1672 = no;
+ RTC_DRV_DS1685_FAMILY = no;
+ RTC_DRV_DS1742 = no;
+ RTC_DRV_DS2404 = no;
+ RTC_DRV_DS3232 = no;
+ RTC_DRV_EM3027 = no;
+ RTC_DRV_FM3130 = no;
+ RTC_DRV_FTRTC010 = no;
+ RTC_DRV_ISL12022 = no;
+ RTC_DRV_ISL1208 = no;
+ RTC_DRV_M41T80 = no;
+ RTC_DRV_M48T35 = no;
+ RTC_DRV_M48T59 = no;
+ RTC_DRV_M48T86 = no;
+ RTC_DRV_MAX6900 = no;
+ RTC_DRV_MAX8907 = no;
+ RTC_DRV_MC13XXX = no;
+ RTC_DRV_MSM6242 = no;
+ RTC_DRV_MT6397 = no;
+ RTC_DRV_PCF2127 = no;
+ RTC_DRV_PCF50633 = no;
+ RTC_DRV_PCF85063 = no;
+ RTC_DRV_PCF8523 = no;
+ RTC_DRV_PCF85363 = no;
+ RTC_DRV_PCF8563 = no;
+ RTC_DRV_PCF8583 = no;
+ RTC_DRV_RP5C01 = no;
+ RTC_DRV_RS5C372 = no;
+ RTC_DRV_RV3028 = no;
+ RTC_DRV_RV3029C2 = no;
+ RTC_DRV_RV8803 = no;
+ RTC_DRV_RX8010 = no;
+ RTC_DRV_RX8025 = no;
+ RTC_DRV_RX8581 = no;
+ RTC_DRV_S35390A = no;
+ RTC_DRV_SD3078 = no;
+ RTC_DRV_STK17TA8 = no;
+ RTC_DRV_V3020 = no;
+ RTC_DRV_X1205 = no;
+ SENSORS_ABITUGURU = no;
+ SENSORS_ABITUGURU3 = no;
+ SENSORS_AD7414 = no;
+ SENSORS_AD7418 = no;
+ SENSORS_ADC128D818 = no;
+ SENSORS_ADM1021 = no;
+ SENSORS_ADM1025 = no;
+ SENSORS_ADM1026 = no;
+ SENSORS_ADM1029 = no;
+ SENSORS_ADM1031 = no;
+ SENSORS_ADM9240 = no;
+ SENSORS_ADS7828 = no;
+ SENSORS_ADT7410 = no;
+ SENSORS_ADT7411 = no;
+ SENSORS_ADT7462 = no;
+ SENSORS_ADT7470 = no;
+ SENSORS_ADT7475 = no;
+ SENSORS_AMC6821 = no;
+ SENSORS_APDS990X = no;
+ SENSORS_APPLESMC = no;
+ SENSORS_AS370 = no;
+ SENSORS_ASB100 = no;
+ SENSORS_ASC7621 = no;
+ SENSORS_ASPEED = no;
+ SENSORS_ATXP1 = no;
+ SENSORS_BH1770 = no;
+ SENSORS_CORETEMP = no;
+ SENSORS_DME1737 = no;
+ SENSORS_DS1621 = no;
+ SENSORS_DS620 = no;
+ SENSORS_EMC1403 = no;
+ SENSORS_EMC2103 = no;
+ SENSORS_EMC6W201 = no;
+ SENSORS_F71805F = no;
+ SENSORS_F71882FG = no;
+ SENSORS_F75375S = no;
+ SENSORS_FSCHMD = no;
+ SENSORS_G760A = no;
+ SENSORS_G762 = no;
+ SENSORS_GL518SM = no;
+ SENSORS_GL520SM = no;
+ SENSORS_HIH6130 = no;
+ SENSORS_INA209 = no;
+ SENSORS_INA2XX = no;
+ SENSORS_INA3221 = no;
+ SENSORS_IT87 = no;
+ SENSORS_JC42 = no;
+ SENSORS_LINEAGE = no;
+ SENSORS_LIS3_I2C = no;
+ SENSORS_LIS3_SPI = module;
+ SENSORS_LM63 = no;
+ SENSORS_LM73 = no;
+ SENSORS_LM75 = no;
+ SENSORS_LM77 = no;
+ SENSORS_LM78 = no;
+ SENSORS_LM80 = no;
+ SENSORS_LM83 = no;
+ SENSORS_LM85 = no;
+ SENSORS_LM87 = no;
+ SENSORS_LM90 = no;
+ SENSORS_LM92 = no;
+ SENSORS_LM93 = no;
+ SENSORS_LM95234 = no;
+ SENSORS_LM95241 = no;
+ SENSORS_LM95245 = no;
+ SENSORS_LTC2945 = no;
+ SENSORS_LTC2990 = no;
+ SENSORS_LTC4151 = no;
+ SENSORS_LTC4215 = no;
+ SENSORS_LTC4222 = no;
+ SENSORS_LTC4245 = no;
+ SENSORS_LTC4260 = no;
+ SENSORS_LTC4261 = no;
+ SENSORS_MAX16065 = no;
+ SENSORS_MAX1619 = no;
+ SENSORS_MAX1668 = no;
+ SENSORS_MAX197 = no;
+ SENSORS_MAX31790 = no;
+ SENSORS_MAX6621 = no;
+ SENSORS_MAX6639 = no;
+ SENSORS_MAX6642 = no;
+ SENSORS_MAX6650 = no;
+ SENSORS_MAX6697 = no;
+ SENSORS_MC13783_ADC = no;
+ SENSORS_MCP3021 = no;
+ SENSORS_MENF21BMC_HWMON = no;
+ SENSORS_NCT6683 = no;
+ SENSORS_NCT6775 = no;
+ SENSORS_NCT7802 = no;
+ SENSORS_NCT7904 = no;
+ SENSORS_NPCM7XX = no;
+ SENSORS_NTC_THERMISTOR = no;
+ SENSORS_PC87360 = no;
+ SENSORS_PC87427 = no;
+ SENSORS_PCF8591 = no;
+ SENSORS_POWR1220 = no;
+ SENSORS_SHT15 = no;
+ SENSORS_SHT21 = no;
+ SENSORS_SHT3x = no;
+ SENSORS_SHTC1 = no;
+ SENSORS_SMM665 = no;
+ SENSORS_SMSC47B397 = no;
+ SENSORS_SMSC47M1 = no;
+ SENSORS_SMSC47M192 = no;
+ SENSORS_STTS751 = no;
+ SENSORS_TC654 = no;
+ SENSORS_TC74 = no;
+ SENSORS_THMC50 = no;
+ SENSORS_TMP102 = no;
+ SENSORS_TMP103 = no;
+ SENSORS_TMP108 = no;
+ SENSORS_TMP401 = no;
+ SENSORS_TMP421 = no;
+ SENSORS_TSL2550 = no;
+ SENSORS_VIA_CPUTEMP = no;
+ SENSORS_VT1211 = no;
+ SENSORS_W83627EHF = no;
+ SENSORS_W83627HF = no;
+ SENSORS_W83773G = no;
+ SENSORS_W83781D = no;
+ SENSORS_W83791D = no;
+ SENSORS_W83792D = no;
+ SENSORS_W83793 = no;
+ SENSORS_W83795 = no;
+ SENSORS_W83L785TS = no;
+ SENSORS_W83L786NG = no;
+ SERIAL_NONSTANDARD = no;
+ SFP = no;
+ SIOX = no;
+ SLIMBUS = no;
+ SLIP = no;
+ SND_HDA_INTEL_DETECT_DMIC = no;
+ SND_SOC = no;
+ SND_X86 = no;
+ SND_XEN_FRONTEND = no;
+ SPI_MEM = no;
+ SPMI = no;
+ STE10XP = no;
+ STM = no;
+ TARGET_CORE = no;
+ TCG_ATMEL = no;
+ TCG_NSC = no;
+ TCG_TIS_ST33ZP24_I2C = no;
+ TCG_VTPM_PROXY = no;
+ TCG_XEN = no;
+ TELCLOCK = no;
+ TERANETICS_PHY = no;
+ THERMAL = no;
+ THUNDERBOLT = no;
+ TRACE_SINK = no;
+ UIO_PRUSS = no;
+ USB_SUPPORT = no;
+ UWB = no;
+ VIRTUALIZATION = no;
+ VITESSE_PHY = no;
+ WATCHDOG = no;
+ WIMAX = no;
+ WIRELESS = no;
+ WLAN = no;
+ X86_EXTENDED_PLATFORM = no;
+ X86_INTEL_MEMORY_PROTECTION_KEYS = no;
+ X86_PLATFORM_DEVICES = no;
+ XEN_BACKEND = no;
+ XEN_BLKDEV_FRONTEND = no;
+ XEN_NETDEV_FRONTEND = no;
+ XEN_XENBUS_FRONTEND = module;
+ XILINX_GMII2RGMII = no;
+ XILINX_SDFEC = no;
};
}
--
So here is a first draft for a more minimal kernel. It brings down the
kernel build time from around 40 minutes to around 10 minutes on my
machine (while watching videos on the side, so ymmv).
What I did was taking the kernel .config from a running spectrum vm and
worked with menuconfig and diffconfig from the kernel source tree.
I tried to remove as much support for physical devices as possible, on
top of that I removed support for virtual hosting and virtual guest for
everything that isn't kvm/virtio.
I tested the kernel by booting it up succesfully and confirming that
video acceleration still works.
I'm not satisfied with the missing documentation right now, but I'm not
sure how to practically improve on that, the sheer number of needed
changes seems to make that pretty hard, so I'd be happy for any suggestions.
Cheers,
Philipp
1
0
Last week I wasn't feeling well, so there was no This Week in Spectrum.
crosvm
------
Where we left off, I had been attempting to port vhost-user-net support
from cloud-hypervisor to crosvm. I'd been trying to port the first
incarnation of the code in cloud-hypervisor to the contemporary version
of crosvm from when it was added, thinking that that would be easier
because the two codebases together. But I ran into the problem that
this earliest incarnation of the vhost-user-net code from
cloud-hypervisor didn't actually work (at least with the backend I was
attempting to test it with). I'd been attempting to figure out exactly
which changes were required to make it work, but hadn't been successful
with that yet, and I thought I'd probably need to start the port over,
from the latest cloud-hypervisor and crosvm code.
The next day, I decided to give my previous strategy one more try,
though, and an hour or two later, I found the required cloud-hypervisor
change, applied it to crosvm, and it worked! So I now have a crosvm
tree capable of vhost-user-net[1].
This means that it's looking good for my plans for inter-guest
networking, and network hardware isolation. With that in place, I
decided to start thinking about other kinds of hardware isolation and
inter-VM communication, and that's what I did for most of the last two
weeks. Let's go through them:
Files will be shared between VMs using virtio-fs. This has the
unique feature of (soon) being able to bypass guest page caches, and
have only a single shared cache between VMs. This brings a performance
improvement, but as I understand it, should also reduce memory
consumption because each VM won't have to maintain its own copy of a
disk-backed page. Of course, this feature (DAX) is also a big side
channel, so it won't be appropriate for all use cases. But I think for
some things people want to do with Spectrum, this will be very
important.
The problem with this is that, because it uses the page cache of the
host kernel, the host has to know about the filesystem that's being
shared -- there's no running virtiofsd in a VM if we want DAX. But I'd
really like it if a (non-boot) block device could be used as a
filesystem without the host having to actually talk to the device. I
was stuck here, but edef pointed out to me that we could use the
kernel's 9P support to attach the block device to a VM, and then
mounting the filesystem in the host over 9P, either over a network
connection or (ideally) vsock. It looks like the kernel should be able
to handle 9P over vsock, but I haven't tested yet. We can use existing
virtiofsd and 9P software (there are promising Rust implementations of
each), and harden them against potential vulnerabilites like directory
traversals using kernel features like RESOLVE_BENEATH and
RESOLVE_NO_XDEV. For the boot device, maybe there's no reason not to
just mount it using the host kernel, or maybe there's something to be
gained by just reading a small bootstrap payload into memory from the
start of the disk once, and then making all future communication go via
a VM. I'm not really sure yet. But the important thing is we'll have
mechanisms for all this in place. Maybe we'll decide that non-boot
devices should just go over inter-VM 9P, but in any case, we'll still
need all these pieces.
GPU isolation should be possible by forwarding the GPU to a VM, but
there are a few problems here. The first is that it would mean rendered
surfaces have to be copied via shared memory to the VM with the GPU,
before being sent to the GPU. Additionally, sharing the GPU between VMs
for rendering at all would require significantly more work. The result
of this is that graphics performance using an isolated GPU will probably
be poor, at least for now. The final problem is that passthrough of
integrated GPUs seems to be very difficult to get right. I will
probably need to acquire some hardware that I've sene a report of this
working on, so I can figure out what I've been doing wrong on the two
computers I've tried it on so far. I suspect that I will get GPU
isolation working, but I'm not sure how reliable or performant it will
be.
For generic USB devices, I expect to be able to take an approach similar
to Qubes[2], having a VM to handle interactions with the hardware USB
controller, and exposing individual USB devices over USB/IP to other
VMs. It would be nice if I could use vsock for this too.
[1]: https://spectrum-os.org/git/crosvm/?h=vhost-user-net
[2]: https://www.qubes-os.org/doc/usb-devices/
spectrum-os.org
---------------
Philipp registered a Matrix room and bridged it to the #spectrum IRC
channel. I'm told that this should make it easier for Matrix users to
join the room, since some bug in Matrix's IRC bridge prevents people
from joining from Matrix the usual way. Philipp also sent a patch[3] to
improve the instructions for Matrix users joining the channel on the
website. Thanks Philipp!
[3]: https://spectrum-os.org/lists/archives/spectrum-devel/87wo247zu7.fsf@alyssa…
QEMU
----
I sent the previously requested patch[4] to resolve ambiguities in the
vhost-user spec. No response yet, though. I'll probably resend it some
time soon.
[4]: https://lore.kernel.org/qemu-devel/20200813094847.4288-1-hi@alyssa.is/
I'm finding it hard to keep going at the moment. The stuff I'm doing
now is probably the hardest part of implementing Spectrum, and it's
frustrating to realise that not everything I want to do is going to be
possible. So much of the KVM ecosystem assumes that things will be
host<->guest, and there's not always an easy solution. But, whatever we
end up with, it's going to be a lot better than what I'm using today,
and what lots of other people are using today. I think I'm going to be
able to deliver a good experience with a fairly high degree of
protection against malicious hardware. But it's not going to be
perfect.
I'm pushing quite hard to make it over the line with my hardware
isolation funding milestone. I'm so close, and I'm about to need the
money. But once I've hit that, I think I'm going to need a break. This
stuff is gruelling.
2
1
Programs assume this and it's useful to have.
---
pkgs/os-specific/linux/spectrum/rootfs/generic.nix | 2 +-
pkgs/os-specific/linux/spectrum/rootfs/stage1.nix | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/pkgs/os-specific/linux/spectrum/rootfs/generic.nix b/pkgs/os-specific/linux/spectrum/rootfs/generic.nix
index 778b18dafa0..0a99f99bd5b 100644
--- a/pkgs/os-specific/linux/spectrum/rootfs/generic.nix
+++ b/pkgs/os-specific/linux/spectrum/rootfs/generic.nix
@@ -31,7 +31,7 @@ let
mkdir $out
cd $out
- mkdir bin sbin dev proc run tmp
+ mkdir bin sbin dev proc run sys tmp
ln -s ${dash}/bin/dash bin/sh
ln -s ${makeStage1 { inherit run; }} sbin/init
cp -r ${./etc} etc
diff --git a/pkgs/os-specific/linux/spectrum/rootfs/stage1.nix b/pkgs/os-specific/linux/spectrum/rootfs/stage1.nix
index 75cfed56e7f..be7853316e9 100644
--- a/pkgs/os-specific/linux/spectrum/rootfs/stage1.nix
+++ b/pkgs/os-specific/linux/spectrum/rootfs/stage1.nix
@@ -27,6 +27,7 @@ writeScript "init-stage1" ''
if { s6-mount -t devpts -o gid=4,mode=620 none /dev/pts }
if { s6-mount -t tmpfs none /dev/shm }
if { s6-mount -t proc none /proc }
+ if { s6-mount -t sysfs none /sys }
if { s6-ln -s ${mesa.drivers} /run/opengl-driver }
export HOME /
--
2.27.0
1
0
Hi!
I read that development ist struggeling with long kernel build times
right now and as a former gentoo kid, I feel somewhat qualified to help
with that.
I had a look at the current way, nixos is building the kernel and I
think it's somewhat over engineered for spectrums needs right now, so I
propose to do the following:
* Exctract the current generic kernel .config from nixos
* make menuconfig with that on a generic linux kernel of the version
currently used in spectrum and remove as many modules as I can
* Circumvent the current nixos kernel configuration pretty much entirely
and supply the kernel .config by adding it directly to the git
repository for faster iteration
When a more elaborate kernel configuration scheme is needed again in the
future, the nixos one is still there and can be properly ported to
spectrums needs but right now I feel like it would only slow the process
down.
However I don't have much experience with the code, so when I get told
here that it's probably better to keep closer to nixpkgs, I'll give my
best with that, too.
Philipp
1
0
I'm a matrix user and fiddled around with the room there a bit. My
findings were that the room itself seems to be fine, but the pretty
alias is broken in some way that I don't understand. I came up with two
ways to join the room via the internal ID and I also took the liberty to
modify the old workaround a little and made it more precise.
---
participating.html | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/participating.html b/participating.html
index 811fcf4..58f2ff3 100644
--- a/participating.html
+++ b/participating.html
@@ -78,13 +78,15 @@ the web.
<h3>Note for Matrix users</h3>
<p>
-There appears to be an issue with Matrix's IRC bridge that prevents
-Matrix users from joining #spectrum. The workaround is as follows:
+There appears to be an issue with Matrix's IRC bridged room that prevents
+Matrix users from joining the channel with the normal alias <q>#freenode_#spectrum:matrix.org</q>. There are the following workarounds:
+
+<ul>
+ <li>Join the room via it's internal name: <q>/join !ZsIiqZmCTSWHpTQWaw:matrix.org</q>.
+ <li>Join the room via <a href="https://matrix.to/#/!ZsIiqZmCTSWHpTQWaw:matrix.org">matrix.to link</a>.</li>
+ <li>Ask the bridges appservice to invite you to the room: <q>/msg @appservice-irc:matrix.org !join #spectrum</q> and accept the invite.</li>
+</ul>
-<ol>
- <li>Post <q>!join #spectrum</q> in your "Freenode IRC Bridge" chat.</li>
- <li>Accept the invitation you are sent.</li>
-</ol>
<p>
If you experience this issue, kindly report it to the people who run
--
2.28.0
3
5
I want to make sure we're collecting copyright information right from
the start, because it's much easier to keep track of this as content
is created, rather than try to piece it together after the fact should
we ever need to.
---
CONTRIBUTING | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/CONTRIBUTING b/CONTRIBUTING
index b2941cf..6cbc106 100644
--- a/CONTRIBUTING
+++ b/CONTRIBUTING
@@ -17,6 +17,14 @@ self-close?), and CSS to a minimum. We want to optimise for the
website being as nice as possible to navigate in a text editor, to
encourage people to edit and improve the website.
+For any changes that are likely to be copyrightable (i.e. those that
+involve any amount of creative input from you), please add an
+SPDX-FileCopyrightText header to the file so we can keep track of
+copyright holders. Every file should already have at least one
+example of these that you can use as a template. If you'd rather not
+list your email address in the copyright notice, it's fine to omit
+that.
+
Please send patches to devel(a)spectrum-os.org. Instructions for how to
do this are provided in the contributing.html file.
--
2.27.0
2
2
See <https://reuse.software/>. NLnet are quite keen on this.
---
CONTRIBUTING | 3 +
LICENSES/CC-BY-SA-4.0.txt | 350 ++++++++++++++++++
LICENSES/CC0-1.0.txt | 119 +++++++
LICENSES/GFDL-1.3-or-later.txt | 416 ++++++++++++++++++++++
LICENSES/GPL-3.0-or-later.txt | 625 +++++++++++++++++++++++++++++++++
README | 7 +-
bibliography.html | 3 +
contributing.html | 3 +
design.html | 3 +
doc/index.html | 3 +
index.html | 3 +
motivation.html | 3 +
participating.html | 3 +
style.css | 3 +
todo.html | 3 +
15 files changed, 1543 insertions(+), 4 deletions(-)
create mode 100644 LICENSES/CC-BY-SA-4.0.txt
create mode 100644 LICENSES/CC0-1.0.txt
create mode 100644 LICENSES/GFDL-1.3-or-later.txt
create mode 100644 LICENSES/GPL-3.0-or-later.txt
diff --git a/CONTRIBUTING b/CONTRIBUTING
index 7ec8fba..b2941cf 100644
--- a/CONTRIBUTING
+++ b/CONTRIBUTING
@@ -1,3 +1,6 @@
+SPDX-FileCopyrightText: 2019 Alyssa Ross <hi(a)alyssa.is>
+SPDX-License-Identifier: CC0-1.0
+
----------------------------------------------------------------------
This file provides instructions for contributing to the website hosted
at <https://spectrum-os.org/>. If you would like to contribute to the
diff --git a/LICENSES/CC-BY-SA-4.0.txt b/LICENSES/CC-BY-SA-4.0.txt
new file mode 100644
index 0000000..f50cdd3
--- /dev/null
+++ b/LICENSES/CC-BY-SA-4.0.txt
@@ -0,0 +1,350 @@
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diff --git a/LICENSES/CC0-1.0.txt b/LICENSES/CC0-1.0.txt
new file mode 100644
index 0000000..a343ccd
--- /dev/null
+++ b/LICENSES/CC0-1.0.txt
@@ -0,0 +1,119 @@
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+2. Waiver. To the greatest extent permitted by, but not in contravention of,
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diff --git a/LICENSES/GFDL-1.3-or-later.txt b/LICENSES/GFDL-1.3-or-later.txt
new file mode 100644
index 0000000..90f814d
--- /dev/null
+++ b/LICENSES/GFDL-1.3-or-later.txt
@@ -0,0 +1,416 @@
+GNU Free Documentation License
+
+Version 1.3, 3 November 2008 Copyright (C) 2000, 2001, 2002, 2007, 2008 Free
+Software Foundation, Inc. <http://fsf.org/>
+
+Everyone is permitted to copy and distribute verbatim copies of this license
+document, but changing it is not allowed.
+
+ 0. PREAMBLE
+
+The purpose of this License is to make a manual, textbook, or other functional
+and useful document "free" in the sense of freedom: to assure everyone the
+effective freedom to copy and redistribute it, with or without modifying it,
+either commercially or noncommercially. Secondarily, this License preserves
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+
+This License is a kind of "copyleft", which means that derivative works of
+the document must themselves be free in the same sense. It complements the
+GNU General Public License, which is a copyleft license designed for free
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+
+We have designed this License in order to use it for manuals for free software,
+because free software needs free documentation: a free program should come
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+License is not limited to software manuals; it can be used for any textual
+work, regardless of subject matter or whether it is published as a printed
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+
+ 1. APPLICABILITY AND DEFINITIONS
+
+This License applies to any manual or other work, in any medium, that contains
+a notice placed by the copyright holder saying it can be distributed under
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+A "Modified Version" of the Document means any work containing the Document
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+A "Secondary Section" is a named appendix or a front-matter section of the
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+The "Invariant Sections" are certain Secondary Sections whose titles are designated,
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+A "Transparent" copy of the Document means a machine-readable copy, represented
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+The "Title Page" means, for a printed book, the title page itself, plus such
+following pages as are needed to hold, legibly, the material this License
+requires to appear in the title page. For works in formats which do not have
+any title page as such, "Title Page" means the text near the most prominent
+appearance of the work's title, preceding the beginning of the body of the
+text.
+
+The "publisher" means any person or entity that distributes copies of the
+Document to the public.
+
+A section "Entitled XYZ" means a named subunit of the Document whose title
+either is precisely XYZ or contains XYZ in parentheses following text that
+translates XYZ in another language. (Here XYZ stands for a specific section
+name mentioned below, such as "Acknowledgements", "Dedications", "Endorsements",
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+
+The Document may include Warranty Disclaimers next to the notice which states
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+considered to be included by reference in this License, but only as regards
+disclaiming warranties: any other implication that these Warranty Disclaimers
+may have is void and has no effect on the meaning of this License.
+
+ 2. VERBATIM COPYING
+
+You may copy and distribute the Document in any medium, either commercially
+or noncommercially, provided that this License, the copyright notices, and
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+in all copies, and that you add no other conditions whatsoever to those of
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+You may also lend copies, under the same conditions stated above, and you
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+
+ 3. COPYING IN QUANTITY
+
+If you publish printed copies (or copies in media that commonly have printed
+covers) of the Document, numbering more than 100, and the Document's license
+notice requires Cover Texts, you must enclose the copies in covers that carry,
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+If the required texts for either cover are too voluminous to fit legibly,
+you should put the first ones listed (as many as fit reasonably) on the actual
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+
+If you publish or distribute Opaque copies of the Document numbering more
+than 100, you must either include a machine-readable Transparent copy along
+with each Opaque copy, or state in or with each Opaque copy a computer-network
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+
+It is requested, but not required, that you contact the authors of the Document
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+to provide you with an updated version of the Document.
+
+ 4. MODIFICATIONS
+
+You may copy and distribute a Modified Version of the Document under the conditions
+of sections 2 and 3 above, provided that you release the Modified Version
+under precisely this License, with the Modified Version filling the role of
+the Document, thus licensing distribution and modification of the Modified
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+
+A. Use in the Title Page (and on the covers, if any) a title distinct from
+that of the Document, and from those of previous versions (which should, if
+there were any, be listed in the History section of the Document). You may
+use the same title as a previous version if the original publisher of that
+version gives permission.
+
+B. List on the Title Page, as authors, one or more persons or entities responsible
+for authorship of the modifications in the Modified Version, together with
+at least five of the principal authors of the Document (all of its principal
+authors, if it has fewer than five), unless they release you from this requirement.
+
+C. State on the Title page the name of the publisher of the Modified Version,
+as the publisher.
+
+ D. Preserve all the copyright notices of the Document.
+
+E. Add an appropriate copyright notice for your modifications adjacent to
+the other copyright notices.
+
+F. Include, immediately after the copyright notices, a license notice giving
+the public permission to use the Modified Version under the terms of this
+License, in the form shown in the Addendum below.
+
+G. Preserve in that license notice the full lists of Invariant Sections and
+required Cover Texts given in the Document's license notice. H. Include an
+unaltered copy of this License.
+
+I. Preserve the section Entitled "History", Preserve its Title, and add to
+it an item stating at least the title, year, new authors, and publisher of
+the Modified Version as given on the Title Page. If there is no section Entitled
+"History" in the Document, create one stating the title, year, authors, and
+publisher of the Document as given on its Title Page, then add an item describing
+the Modified Version as stated in the previous sentence.
+
+J. Preserve the network location, if any, given in the Document for public
+access to a Transparent copy of the Document, and likewise the network locations
+given in the Document for previous versions it was based on. These may be
+placed in the "History" section. You may omit a network location for a work
+that was published at least four years before the Document itself, or if the
+original publisher of the version it refers to gives permission.
+
+K. For any section Entitled "Acknowledgements" or "Dedications", Preserve
+the Title of the section, and preserve in the section all the substance and
+tone of each of the contributor acknowledgements and/or dedications given
+therein.
+
+L. Preserve all the Invariant Sections of the Document, unaltered in their
+text and in their titles. Section numbers or the equivalent are not considered
+part of the section titles.
+
+M. Delete any section Entitled "Endorsements". Such a section may not be included
+in the Modified Version.
+
+N. Do not retitle any existing section to be Entitled "Endorsements" or to
+conflict in title with any Invariant Section.
+
+ O. Preserve any Warranty Disclaimers.
+
+If the Modified Version includes new front-matter sections or appendices that
+qualify as Secondary Sections and contain no material copied from the Document,
+you may at your option designate some or all of these sections as invariant.
+To do this, add their titles to the list of Invariant Sections in the Modified
+Version's license notice. These titles must be distinct from any other section
+titles.
+
+You may add a section Entitled "Endorsements", provided it contains nothing
+but endorsements of your Modified Version by various parties--for example,
+statements of peer review or that the text has been approved by an organization
+as the authoritative definition of a standard.
+
+You may add a passage of up to five words as a Front-Cover Text, and a passage
+of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts
+in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover
+Text may be added by (or through arrangements made by) any one entity. If
+the Document already includes a cover text for the same cover, previously
+added by you or by arrangement made by the same entity you are acting on behalf
+of, you may not add another; but you may replace the old one, on explicit
+permission from the previous publisher that added the old one.
+
+The author(s) and publisher(s) of the Document do not by this License give
+permission to use their names for publicity for or to assert or imply endorsement
+of any Modified Version.
+
+ 5. COMBINING DOCUMENTS
+
+You may combine the Document with other documents released under this License,
+under the terms defined in section 4 above for modified versions, provided
+that you include in the combination all of the Invariant Sections of all of
+the original documents, unmodified, and list them all as Invariant Sections
+of your combined work in its license notice, and that you preserve all their
+Warranty Disclaimers.
+
+The combined work need only contain one copy of this License, and multiple
+identical Invariant Sections may be replaced with a single copy. If there
+are multiple Invariant Sections with the same name but different contents,
+make the title of each such section unique by adding at the end of it, in
+parentheses, the name of the original author or publisher of that section
+if known, or else a unique number. Make the same adjustment to the section
+titles in the list of Invariant Sections in the license notice of the combined
+work.
+
+In the combination, you must combine any sections Entitled "History" in the
+various original documents, forming one section Entitled "History"; likewise
+combine any sections Entitled "Acknowledgements", and any sections Entitled
+"Dedications". You must delete all sections Entitled "Endorsements".
+
+ 6. COLLECTIONS OF DOCUMENTS
+
+You may make a collection consisting of the Document and other documents released
+under this License, and replace the individual copies of this License in the
+various documents with a single copy that is included in the collection, provided
+that you follow the rules of this License for verbatim copying of each of
+the documents in all other respects.
+
+You may extract a single document from such a collection, and distribute it
+individually under this License, provided you insert a copy of this License
+into the extracted document, and follow this License in all other respects
+regarding verbatim copying of that document.
+
+ 7. AGGREGATION WITH INDEPENDENT WORKS
+
+A compilation of the Document or its derivatives with other separate and independent
+documents or works, in or on a volume of a storage or distribution medium,
+is called an "aggregate" if the copyright resulting from the compilation is
+not used to limit the legal rights of the compilation's users beyond what
+the individual works permit. When the Document is included in an aggregate,
+this License does not apply to the other works in the aggregate which are
+not themselves derivative works of the Document.
+
+If the Cover Text requirement of section 3 is applicable to these copies of
+the Document, then if the Document is less than one half of the entire aggregate,
+the Document's Cover Texts may be placed on covers that bracket the Document
+within the aggregate, or the electronic equivalent of covers if the Document
+is in electronic form. Otherwise they must appear on printed covers that bracket
+the whole aggregate.
+
+ 8. TRANSLATION
+
+Translation is considered a kind of modification, so you may distribute translations
+of the Document under the terms of section 4. Replacing Invariant Sections
+with translations requires special permission from their copyright holders,
+but you may include translations of some or all Invariant Sections in addition
+to the original versions of these Invariant Sections. You may include a translation
+of this License, and all the license notices in the Document, and any Warranty
+Disclaimers, provided that you also include the original English version of
+this License and the original versions of those notices and disclaimers. In
+case of a disagreement between the translation and the original version of
+this License or a notice or disclaimer, the original version will prevail.
+
+If a section in the Document is Entitled "Acknowledgements", "Dedications",
+or "History", the requirement (section 4) to Preserve its Title (section 1)
+will typically require changing the actual title.
+
+ 9. TERMINATION
+
+You may not copy, modify, sublicense, or distribute the Document except as
+expressly provided under this License. Any attempt otherwise to copy, modify,
+sublicense, or distribute it is void, and will automatically terminate your
+rights under this License.
+
+However, if you cease all violation of this License, then your license from
+a particular copyright holder is reinstated (a) provisionally, unless and
+until the copyright holder explicitly and finally terminates your license,
+and (b) permanently, if the copyright holder fails to notify you of the violation
+by some reasonable means prior to 60 days after the cessation.
+
+Moreover, your license from a particular copyright holder is reinstated permanently
+if the copyright holder notifies you of the violation by some reasonable means,
+this is the first time you have received notice of violation of this License
+(for any work) from that copyright holder, and you cure the violation prior
+to 30 days after your receipt of the notice.
+
+Termination of your rights under this section does not terminate the licenses
+of parties who have received copies or rights from you under this License.
+If your rights have been terminated and not permanently reinstated, receipt
+of a copy of some or all of the same material does not give you any rights
+to use it.
+
+ 10. FUTURE REVISIONS OF THIS LICENSE
+
+The Free Software Foundation may publish new, revised versions of the GNU
+Free Documentation License from time to time. Such new versions will be similar
+in spirit to the present version, but may differ in detail to address new
+problems or concerns. See http://www.gnu.org/copyleft/.
+
+Each version of the License is given a distinguishing version number. If the
+Document specifies that a particular numbered version of this License "or
+any later version" applies to it, you have the option of following the terms
+and conditions either of that specified version or of any later version that
+has been published (not as a draft) by the Free Software Foundation. If the
+Document does not specify a version number of this License, you may choose
+any version ever published (not as a draft) by the Free Software Foundation.
+If the Document specifies that a proxy can decide which future versions of
+this License can be used, that proxy's public statement of acceptance of a
+version permanently authorizes you to choose that version for the Document.
+
+ 11. RELICENSING
+
+"Massive Multiauthor Collaboration Site" (or "MMC Site") means any World Wide
+Web server that publishes copyrightable works and also provides prominent
+facilities for anybody to edit those works. A public wiki that anybody can
+edit is an example of such a server. A "Massive Multiauthor Collaboration"
+(or "MMC") contained in the site means any set of copyrightable works thus
+published on the MMC site.
+
+"CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0 license
+published by Creative Commons Corporation, a not-for-profit corporation with
+a principal place of business in San Francisco, California, as well as future
+copyleft versions of that license published by that same organization.
+
+"Incorporate" means to publish or republish a Document, in whole or in part,
+as part of another Document.
+
+An MMC is "eligible for relicensing" if it is licensed under this License,
+and if all works that were first published under this License somewhere other
+than this MMC, and subsequently incorporated in whole or in part into the
+MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated
+prior to November 1, 2008.
+
+The operator of an MMC Site may republish an MMC contained in the site under
+CC-BY-SA on the same site at any time before August 1, 2009, provided the
+MMC is eligible for relicensing. ADDENDUM: How to use this License for your
+documents
+
+To use this License in a document you have written, include a copy of the
+License in the document and put the following copyright and license notices
+just after the title page:
+
+Copyright (c) YEAR YOUR NAME. Permission is granted to copy, distribute and/or
+modify this document under the terms of the GNU Free Documentation License,
+Version 1.3 or any later version published by the Free Software Foundation;
+with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
+A copy of the license is included in the section entitled "GNU Free Documentation
+License".
+
+If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace
+the "with...Texts." line with this:
+
+with the Invariant Sections being LIST THEIR TITLES, with the Front-Cover
+Texts being LIST, and with the Back-Cover Texts being LIST.
+
+If you have Invariant Sections without Cover Texts, or some other combination
+of the three, merge those two alternatives to suit the situation.
+
+If your document contains nontrivial examples of program code, we recommend
+releasing these examples in parallel under your choice of free software license,
+such as the GNU General Public License, to permit their use in free software.
diff --git a/LICENSES/GPL-3.0-or-later.txt b/LICENSES/GPL-3.0-or-later.txt
new file mode 100644
index 0000000..e142a52
--- /dev/null
+++ b/LICENSES/GPL-3.0-or-later.txt
@@ -0,0 +1,625 @@
+GNU GENERAL PUBLIC LICENSE
+
+Version 3, 29 June 2007
+
+Copyright © 2007 Free Software Foundation, Inc. <https://fsf.org/>
+
+Everyone is permitted to copy and distribute verbatim copies of this license
+document, but changing it is not allowed.
+
+Preamble
+
+The GNU General Public License is a free, copyleft license for software and
+other kinds of works.
+
+The licenses for most software and other practical works are designed to take
+away your freedom to share and change the works. By contrast, the GNU General
+Public License is intended to guarantee your freedom to share and change all
+versions of a program--to make sure it remains free software for all its users.
+We, the Free Software Foundation, use the GNU General Public License for most
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+authors. You can apply it to your programs, too.
+
+When we speak of free software, we are referring to freedom, not price. Our
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+
+To protect your rights, we need to prevent others from denying you these rights
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+if you distribute copies of the software, or if you modify it: responsibilities
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+
+For example, if you distribute copies of such a program, whether gratis or
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+you must show them these terms so they know their rights.
+
+Developers that use the GNU GPL protect your rights with two steps: (1) assert
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+
+For the developers' and authors' protection, the GPL clearly explains that
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+
+Some devices are designed to deny users access to install or run modified
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+Finally, every program is threatened constantly by software patents. States
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+
+The precise terms and conditions for copying, distribution and modification
+follow.
+
+TERMS AND CONDITIONS
+
+ 0. Definitions.
+
+ "This License" refers to version 3 of the GNU General Public License.
+
+"Copyright" also means copyright-like laws that apply to other kinds of works,
+such as semiconductor masks.
+
+"The Program" refers to any copyrightable work licensed under this License.
+Each licensee is addressed as "you". "Licensees" and "recipients" may be individuals
+or organizations.
+
+To "modify" a work means to copy from or adapt all or part of the work in
+a fashion requiring copyright permission, other than the making of an exact
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+
+A "covered work" means either the unmodified Program or a work based on the
+Program.
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+
+ 7. Additional Terms.
+
+"Additional permissions" are terms that supplement the terms of this License
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+that are applicable to the entire Program shall be treated as though they
+were included in this License, to the extent that they are valid under applicable
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+may be used separately under those permissions, but the entire Program remains
+governed by this License without regard to the additional permissions.
+
+When you convey a copy of a covered work, you may at your option remove any
+additional permissions from that copy, or from any part of it. (Additional
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+you modify the work.) You may place additional permissions on material, added
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+Notwithstanding any other provision of this License, for material you add
+to a covered work, you may (if authorized by the copyright holders of that
+material) supplement the terms of this License with terms:
+
+a) Disclaiming warranty or limiting liability differently from the terms of
+sections 15 and 16 of this License; or
+
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+
+All other non-permissive additional terms are considered "further restrictions"
+within the meaning of section 10. If the Program as you received it, or any
+part of it, contains a notice stating that it is governed by this License
+along with a term that is a further restriction, you may remove that term.
+If a license document contains a further restriction but permits relicensing
+or conveying under this License, you may add to a covered work material governed
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+
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+
+Additional terms, permissive or non-permissive, may be stated in the form
+of a separately written license, or stated as exceptions; the above requirements
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+ 8. Termination.
+
+You may not propagate or modify a covered work except as expressly provided
+under this License. Any attempt otherwise to propagate or modify it is void,
+and will automatically terminate your rights under this License (including
+any patent licenses granted under the third paragraph of section 11).
+
+However, if you cease all violation of this License, then your license from
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+and (b) permanently, if the copyright holder fails to notify you of the violation
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+
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+this is the first time you have received notice of violation of this License
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+
+Termination of your rights under this section does not terminate the licenses
+of parties who have received copies or rights from you under this License.
+If your rights have been terminated and not permanently reinstated, you do
+not qualify to receive new licenses for the same material under section 10.
+
+ 9. Acceptance Not Required for Having Copies.
+
+You are not required to accept this License in order to receive or run a copy
+of the Program. Ancillary propagation of a covered work occurring solely as
+a consequence of using peer-to-peer transmission to receive a copy likewise
+does not require acceptance. However, nothing other than this License grants
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+copyright if you do not accept this License. Therefore, by modifying or propagating
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+
+ 10. Automatic Licensing of Downstream Recipients.
+
+Each time you convey a covered work, the recipient automatically receives
+a license from the original licensors, to run, modify and propagate that work,
+subject to this License. You are not responsible for enforcing compliance
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+
+An "entity transaction" is a transaction transferring control of an organization,
+or substantially all assets of one, or subdividing an organization, or merging
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+
+You may not impose any further restrictions on the exercise of the rights
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+license fee, royalty, or other charge for exercise of rights granted under
+this License, and you may not initiate litigation (including a cross-claim
+or counterclaim in a lawsuit) alleging that any patent claim is infringed
+by making, using, selling, offering for sale, or importing the Program or
+any portion of it.
+
+ 11. Patents.
+
+A "contributor" is a copyright holder who authorizes use under this License
+of the Program or a work on which the Program is based. The work thus licensed
+is called the contributor's "contributor version".
+
+A contributor's "essential patent claims" are all patent claims owned or controlled
+by the contributor, whether already acquired or hereafter acquired, that would
+be infringed by some manner, permitted by this License, of making, using,
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+grant patent sublicenses in a manner consistent with the requirements of this
+License.
+
+Each contributor grants you a non-exclusive, worldwide, royalty-free patent
+license under the contributor's essential patent claims, to make, use, sell,
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+In the following three paragraphs, a "patent license" is any express agreement
+or commitment, however denominated, not to enforce a patent (such as an express
+permission to practice a patent or covenant not to sue for patent infringement).
+To "grant" such a patent license to a party means to make such an agreement
+or commitment not to enforce a patent against the party.
+
+If you convey a covered work, knowingly relying on a patent license, and the
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+cause the Corresponding Source to be so available, or (2) arrange to deprive
+yourself of the benefit of the patent license for this particular work, or
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+to extend the patent license to downstream recipients. "Knowingly relying"
+means you have actual knowledge that, but for the patent license, your conveying
+the covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that country
+that you have reason to believe are valid.
+
+If, pursuant to or in connection with a single transaction or arrangement,
+you convey, or propagate by procuring conveyance of, a covered work, and grant
+a patent license to some of the parties receiving the covered work authorizing
+them to use, propagate, modify or convey a specific copy of the covered work,
+then the patent license you grant is automatically extended to all recipients
+of the covered work and works based on it.
+
+A patent license is "discriminatory" if it does not include within the scope
+of its coverage, prohibits the exercise of, or is conditioned on the non-exercise
+of one or more of the rights that are specifically granted under this License.
+You may not convey a covered work if you are a party to an arrangement with
+a third party that is in the business of distributing software, under which
+you make payment to the third party based on the extent of your activity of
+conveying the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory patent
+license (a) in connection with copies of the covered work conveyed by you
+(or copies made from those copies), or (b) primarily for and in connection
+with specific products or compilations that contain the covered work, unless
+you entered into that arrangement, or that patent license was granted, prior
+to 28 March 2007.
+
+Nothing in this License shall be construed as excluding or limiting any implied
+license or other defenses to infringement that may otherwise be available
+to you under applicable patent law.
+
+ 12. No Surrender of Others' Freedom.
+
+If conditions are imposed on you (whether by court order, agreement or otherwise)
+that contradict the conditions of this License, they do not excuse you from
+the conditions of this License. If you cannot convey a covered work so as
+to satisfy simultaneously your obligations under this License and any other
+pertinent obligations, then as a consequence you may not convey it at all.
+For example, if you agree to terms that obligate you to collect a royalty
+for further conveying from those to whom you convey the Program, the only
+way you could satisfy both those terms and this License would be to refrain
+entirely from conveying the Program.
+
+ 13. Use with the GNU Affero General Public License.
+
+Notwithstanding any other provision of this License, you have permission to
+link or combine any covered work with a work licensed under version 3 of the
+GNU Affero General Public License into a single combined work, and to convey
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+General Public License, section 13, concerning interaction through a network
+will apply to the combination as such.
+
+ 14. Revised Versions of this License.
+
+The Free Software Foundation may publish revised and/or new versions of the
+GNU General Public License from time to time. Such new versions will be similar
+in spirit to the present version, but may differ in detail to address new
+problems or concerns.
+
+Each version is given a distinguishing version number. If the Program specifies
+that a certain numbered version of the GNU General Public License "or any
+later version" applies to it, you have the option of following the terms and
+conditions either of that numbered version or of any later version published
+by the Free Software Foundation. If the Program does not specify a version
+number of the GNU General Public License, you may choose any version ever
+published by the Free Software Foundation.
+
+If the Program specifies that a proxy can decide which future versions of
+the GNU General Public License can be used, that proxy's public statement
+of acceptance of a version permanently authorizes you to choose that version
+for the Program.
+
+Later license versions may give you additional or different permissions. However,
+no additional obligations are imposed on any author or copyright holder as
+a result of your choosing to follow a later version.
+
+ 15. Disclaimer of Warranty.
+
+THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE
+LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
+OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
+EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM
+PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR
+CORRECTION.
+
+ 16. Limitation of Liability.
+
+IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL
+ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM
+AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL,
+INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO
+USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED
+INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE
+PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER
+PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+If the disclaimer of warranty and limitation of liability provided above cannot
+be given local legal effect according to their terms, reviewing courts shall
+apply local law that most closely approximates an absolute waiver of all civil
+liability in connection with the Program, unless a warranty or assumption
+of liability accompanies a copy of the Program in return for a fee. END OF
+TERMS AND CONDITIONS
+
+How to Apply These Terms to Your New Programs
+
+If you develop a new program, and you want it to be of the greatest possible
+use to the public, the best way to achieve this is to make it free software
+which everyone can redistribute and change under these terms.
+
+To do so, attach the following notices to the program. It is safest to attach
+them to the start of each source file to most effectively state the exclusion
+of warranty; and each file should have at least the "copyright" line and a
+pointer to where the full notice is found.
+
+<one line to give the program's name and a brief idea of what it does.>
+
+Copyright (C) <year> <name of author>
+
+This program is free software: you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation, either version 3 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with
+this program. If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program does terminal interaction, make it output a short notice like
+this when it starts in an interactive mode:
+
+<program> Copyright (C) <year> <name of author>
+
+This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+
+This is free software, and you are welcome to redistribute it under certain
+conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands might
+be different; for a GUI interface, you would use an "about box".
+
+You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary. For
+more information on this, and how to apply and follow the GNU GPL, see <https://www.gnu.org/licenses/>.
+
+The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library. If this is what you want to do, use the GNU Lesser General Public
+License instead of this License. But first, please read <https://www.gnu.org/
+licenses /why-not-lgpl.html>.
diff --git a/README b/README
index 156141b..359ada0 100644
--- a/README
+++ b/README
@@ -1,3 +1,6 @@
+SPDX-FileCopyrightText: 2019 Alyssa Ross <hi(a)alyssa.is>
+SPDX-License-Identifier: CC0-1.0
+
These files contain the static portion of the website accessible at
<https://spectrum-os.org/>. CGit, Mailman, etc, are run seperately.
@@ -10,7 +13,3 @@ Documentation License (version 1.2 or later), at your option.
The source code of these web pages may be redistributed under the
terms of the GNU General Public License (version 3.0 or later).
-
-CC-BY-SA: <https://creativecommons.org/licenses/by-sa/4.0/>
-GNU Free Documentation License: <https://www.gnu.org/licenses/gfdl.html>
-GNU General Public License: <https://www.gnu.org/licenses/gpl-3.0.en.html>
\ No newline at end of file
diff --git a/bibliography.html b/bibliography.html
index b2ccd0a..ff80215 100644
--- a/bibliography.html
+++ b/bibliography.html
@@ -1,4 +1,7 @@
<!doctype html>
+<!-- SPDX-FileCopyrightText: 2019-2020 Alyssa Ross <hi(a)alyssa.is> -->
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 OR GFDL-1.3-or-later -->
+<!-- SPDX-License-Identifier: GPL-3.0-or-later -->
<html lang="en">
<head>
diff --git a/contributing.html b/contributing.html
index 8999fee..25522fc 100644
--- a/contributing.html
+++ b/contributing.html
@@ -1,4 +1,7 @@
<!doctype html>
+<!-- SPDX-FileCopyrightText: 2019-2020 Alyssa Ross <hi(a)alyssa.is> -->
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 OR GFDL-1.3-or-later -->
+<!-- SPDX-License-Identifier: GPL-3.0-or-later -->
<html lang="en">
<head>
diff --git a/design.html b/design.html
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--- a/design.html
+++ b/design.html
@@ -1,4 +1,7 @@
<!doctype html>
+<!-- SPDX-FileCopyrightText: 2019-2020 Alyssa Ross <hi(a)alyssa.is> -->
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 OR GFDL-1.3-or-later -->
+<!-- SPDX-License-Identifier: GPL-3.0-or-later -->
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<head>
diff --git a/doc/index.html b/doc/index.html
index c6acecc..a77d4ac 100644
--- a/doc/index.html
+++ b/doc/index.html
@@ -1,4 +1,7 @@
<!doctype html>
+<!-- SPDX-FileCopyrightText: 2019-2020 Alyssa Ross <hi(a)alyssa.is> -->
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 OR GFDL-1.3-or-later -->
+<!-- SPDX-License-Identifier: GPL-3.0-or-later -->
<html lang="en">
<head>
diff --git a/index.html b/index.html
index 08974b1..cbea331 100644
--- a/index.html
+++ b/index.html
@@ -1,4 +1,7 @@
<!doctype html>
+<!-- SPDX-FileCopyrightText: 2019-2020 Alyssa Ross <hi(a)alyssa.is> -->
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 OR GFDL-1.3-or-later -->
+<!-- SPDX-License-Identifier: GPL-3.0-or-later -->
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<head>
diff --git a/motivation.html b/motivation.html
index c7d5667..4076263 100644
--- a/motivation.html
+++ b/motivation.html
@@ -1,4 +1,7 @@
<!doctype html>
+<!-- SPDX-FileCopyrightText: 2019-2020 Alyssa Ross <hi(a)alyssa.is> -->
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 OR GFDL-1.3-or-later -->
+<!-- SPDX-License-Identifier: GPL-3.0-or-later -->
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<head>
diff --git a/participating.html b/participating.html
index 2d9acab..811fcf4 100644
--- a/participating.html
+++ b/participating.html
@@ -1,4 +1,7 @@
<!doctype html>
+<!-- SPDX-FileCopyrightText: 2019-2020 Alyssa Ross <hi(a)alyssa.is> -->
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 OR GFDL-1.3-or-later -->
+<!-- SPDX-License-Identifier: GPL-3.0-or-later -->
<html lang="en">
<head>
diff --git a/style.css b/style.css
index b2b23c0..e9fd751 100644
--- a/style.css
+++ b/style.css
@@ -1,3 +1,6 @@
+/* SPDX-FileCopyrightText: 2019 Alyssa Ross <hi(a)alyssa.is> */
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+
/*
Less is more.
*/
diff --git a/todo.html b/todo.html
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--- a/todo.html
+++ b/todo.html
@@ -1,4 +1,7 @@
<!doctype html>
+<!-- SPDX-FileCopyrightText: 2019-2020 Alyssa Ross <hi(a)alyssa.is> -->
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 OR GFDL-1.3-or-later -->
+<!-- SPDX-License-Identifier: GPL-3.0-or-later -->
<html lang="en">
<head>
--
2.27.0
2
2
Last week, I'd just finished getting the cloud-hypervisor vhost-user-net
frontend code to build as part of crosvm, and the next step was testing
it.
crosvm
------
I wrote some hacky code that replaced the virtio-net device creation in
crosvm with an instance of the ported vhost-user-net code. When I
booted crosvm, there were some of the expected simple oversights of mine
that needed to be addressed, but once those were taken care of, it still
didn't quite work. The VM boots, sees a network interface, and even
communicates with the vhost-user-net backend! But, it doesn't quite
work. The vhost-user-net code never realises/gets told that it has
traffic, and so it's never processed. Unsure of what to do about this,
I decided to turn to cloud-hypervisor and look at how the code ran
there.
cloud-hypervisor
----------------
I wanted to try running the cloud-hypervisor v-u-n backend I was using
for testing (because it's much simpler than DPDK -- it just sends
traffic to a TAP device) with QEMU as the
frontend, because QEMU is a VMM I'm familiar with (much more so than
cloud-hypervisor as the frontend), and I thought it would be useful to
have a working frontend/backend combination to compare to.
I had some problems, though, because apparently nobody had ever wanted
to use QEMU with the cloud-hypervisor vhost-user-net backend before --
or if they had, they hadn't wanted to enough to make it work. The
cloud-hypervisor backend didn't implement the vhost-user spec correctly
in a few subtle ways that made it incompatible with QEMU. I won't
explain every subtle issue, but I ended up writing a few patches[1][2]
for cloud-hypervisor and the "vhost" crate it depends on (that is in the
process of being moved under the rust-vmm umbrella).
One interesting issue I will go into a little detail of was that the
wording in the spec was a little unclear, and QEMU interpreted it one
way, and cloud-hypervisor the other. I ended up sending an email[3] to
the author of the spec asking for clarification. He answered my
question, and we discussed how the wording could be improved. He liked
my second attempt at improving my working, and asked me to send a patch,
but preferably not right now, because QEMU is currently gearing up for a
release, scheduled for next week if everything goes well.
Since I wrote these cloud-hypervisor patches, and had to test them, I
ended up having to learn how to use cloud-hypervisor anyway to make sure
I hadn't broken it in fixing the backend up to work with QEMU. Oh well.
Once this was done, I could use both QEMU and cloud-hypervisor with the
backend, but not crosvm. But it was a little more complex than that.
When I ported the v-u-n code to crosvm, I ported the first version of it
that was added to the cloud-hypervisor tree, rather than the latest
version. The theory here was that the earlier version would be closer
to crosvm, because cloud-hypervisor would have had less time to diverge.
Then, once I had that working, I could add on the later changes
gradually. What I didn't account for here is that the initial version
of the v-u-n frontend in cloud-hypervisor didn't really work properly,
and needed some time to bake before it did. So having now had this
experience I think it might be better to try to port the latest version,
and accept that porting might be a bit harder, but the end result is
more likely to work.
[1]: https://github.com/cloud-hypervisor/vhost/pull/22
[2]: https://github.com/cloud-hypervisor/cloud-hypervisor/pull/1565
[3]: https://lore.kernel.org/qemu-devel/87sgd1ktx9.fsf@alyssa.is/
libgit2
-------
While bisecting cloud-hypervisor to see if I could figure out when the
v-u-n frontend started working properly, I encountered a large section
of commits that I couldn't build any more, because Cargo couldn't
resolve a git dependency. The dependency was locked to a commit that
was no longer in the branch it had been in when the cloud-hypervisor
commit was from. Despite knowing the exact commit it needed, Cargo
fetched the branch the commit used to be on. This is because it is
generally not possible to fetch arbitrary commits with git. Some
servers, like GitHub, do however allow this, and I wondered why Cargo
wouldn't at least fall back to trying that.
As it turns out, it actually couldn't do that, though! Cargo uses
libgit2, and libgit2 doesn't support fetching arbitrary commits. So I
wrote a quick patch to libgit2 to support this[4]. It's only a partial
implementation, though, because I don't find libgit2 to be a
particularly easy codebase to work in (although it's better than git!).
So I'm hoping somebody who knows more about it than me will help me
figure out how to finish it.
[4]: https://github.com/libgit2/libgit2/pull/5603
Next week, I'm hoping that I'll be able to get to vhost-user-net in
crosvm working. I think this will probably mean porting the code again,
using the latest version. Which is a bit of a shame, but at least I
have an idea of what to do next.
I am, overall, feeling pretty optimistic, though. I'm pretty confident
that we can get some sort of decent but imperfect network hardware
isolation even though virtio-vhost-user might not be ready yet, which
was something I was worried about before. I don't want to really go
into detail in that now though because this is already a long email and
it's already a day late because I was tired yesterday, but essentially,
we could forward the network device to a VM that would run the driver,
and forward traffic back to the host over virtio-net. The host could
handle this either in kernelspace or userspace with DPDK, but the
important thing is that the only network driver it would need to support
would be virtio-net. No talking to hundreds of different Wi-Fi cards
and hoping that none of the drivers have a vulnerability. So, not
perfect compared to proper guest<->guest networking, but a step in the
right direction, and one that should be as simple as possible to upgrade
to virtio-vhost-user once that becomes possible.
1
0
DPDK
----
Last week, I'd just figured out how to do a normal vhost-user setup with
a QEMU VM connected to DPDK. This week, I wanted to try to move DPDK
into another VM using the experimental virtio-vhost-user driver, taking
the host system out of the networking equation altogether.
In theory this should have been a very simple change, but I couldn't get
it to work. DPDK claimed to be forwarding packets to the ethernet
device I'd attached to the backend VM (the one running DPDK), but
networking in the frontend VM (what you might think of as the
application VM) didn't work at all. It tried and failed to do DHCP, and
so couldn't progress beyond that.
A breakthrough came when I thought to look at the logs of my local DHCP
server. I saw that it was actually receiving requests from the VM, and
assigning it an IP address. Once I realised this, I hypothesised that
outgoing traffic was working, but not incoming.
Finally having something to look for, I had a look through the DPDK
virtio-vhost-user driver[1], and my suspicion was confirmed in an
unexpected way. It looks like incoming traffic (from the perspective of
the virtio-vhost-user frontend) is not actually implemented at all!
But with outbound traffic working, this means that I'm confident enough
I understand virtio-vhost-user enough to be able to leave this here for
now. From Spectrum's side, I can now be pretty sure that everything
should be workable, so we can just wait a bit for virtio-vhost-user to
get a bit further along and then revisit it. And since the frontend
has no idea it's talking to virtio-vhost-user instead of normal
vhost-user, we can use normal (host-based) vhost-user for now, and drop
virtio-vhost-user in down the line.
A couple of outstanding questions I still don't know the answer to about
DPDK are:
- How will routing work if I have multiple frontend VMs with multiple
virtio-vhost-user connections all wanting to use the same network
device? Will I want to use something like Open vSwitch[2] for that?
- DPDK by default uses a busyloop to check for data to process, for
efficiency. This is obviously not appropriate for a
workstation-focused operating system. There is an interrupt-based
mode, though, but I don't know how to use it yet.
Since I consider the concept proven, though, I'm going to punt on these
for now. The longer I leave these questions, the more likely it is that
a kernel driver for virtio-vhost-user will emerge and we can use that
instead. That's not to say I want to leave inter-guest networking
hanging forever, but I have other inter-guest networking bits I can
switch focus to for now, and once those are down I can revisit the
virtio-vhost-user backend situation.
[1]: https://github.com/ndragazis/dpdk-next-virtio/blob/2d60e63/drivers/virtio_v…
[2]: https://www.openvswitch.org/
crosvm
------
I started integrating the vhost-user-net code from Cloud Hypervisor into
crosvm. I'm at the point where I can get all the copied Cloud
Hypervisor code to compile in crosvm, which is pretty good! I have not
yet written the code to actually start one of these devices yet, though,
so I haven't been able to test it yet.
It's been interesting to look at Cloud Hypervisor because it's a
codebase that is heavily based on crosvm (even more so than Firecracker
is), but that has also evolved and diverged from it. It's especially
interesting to see stuff where parallel evolution occurred between the
crosvm and Cloud Hypervisor codebases, or when Cloud Hypervisor changed
how some crosvm code worked, and then later changed it back again.
The codebases were still similar enough that I could have the
cloud-hypervisor device integrated into the crosvm codebase in a day,
although there's lots of code duplication that will have to be dealt
with -- I copied over a bunch of supporting code rather than trying to
integrate it into the crosvm equivalents to get the code running for the
first time in an environment as similar as possible to the one it was
designed for. I expect that when I test the device in crosvm it'll
probably work fairly quickly if not first try. The more complicated
part will be a bit of a change to how crosvm does guest memory that
isn't strictly necessary but is important for security.
crosvm allocates all guest memory in a single memfd. This means that,
to share guest memory with another process, like when using vhost-user,
the only option is to share all of guest memory. This would sort of
defeat the purpose of hardware isolation in Spectrum! But from what I
could tell -- I'm not 100% on this -- the guest memory abstraction in
cloud-hypervisor is more advanced, and I think it might support multiple
memfds backing guest memory for this sort of thing. I'll have to adapt
crosvm to that model to be able to use vhost-user securely.
website
-------
The new "Bibliography" page is up[3]! Lots of links to relevant resources
about concepts important to Spectrum. :)
[3]: https://spectrum-os.org/bibliography.html
It's a bit of a relief to have returned from the uncertain world of DPDK
to the familiar territory of crosvm. I'm confident that the next bit of
work here (vhost-user in crosvm) won't be that much of a big deal.
Hopefully, we'll have at interim networking to a reasonable degree
fairly soon. After that, I plan to look at file sharing, possibly with
vhost-user-fs (virtio-fs over vhost-user), which I noticed
cloud-hypervisor implements today. That should be pretty similar to the
networking stuff, although I don't think any virtio-fs virtio-vhost-user
code exists at the moment.
1
0