lkmc v2-rc

Unsquashed version at v2-rc-unsquashed, but that cannot be merged as it
breaks bisects at several points. All bugs will not bisect to this
humongous change.

It all started with a conversion of the Bash scripts to Python, mainly
because I couldn't stand not being able to properly use --options for
run which has a million options.

Then since that required a full testing, I decided to do all the
refactorings that I had in mind at once, and so I did and it became
v2-rc.

This is the largest patch I have ever done! OMG a few weeks of extra time.
I'm never writing a Bash script for anything that starts getting big again.

Some of the features are:

* separate build-qemu and build-gem5 commands
* common: convert scripts to python. Add --option for everything
* rename build to build-buildroot now that we are splitting all the build
  commands, Linux kernel to follow
* move all git submodules to submodules/ and all buildroot packages to
  packages/
* refactor the out/ structure. Keep projects on toplevel, because guest
  projects separate archs and host ones don't, making a toplevel arch wrong
* do-release: rename to just release
  https://stackoverflow.com/questions/16174992/cant-get-argparse-to-read-quoted-string-with-dashes-in-it
* run: add --terminal and explain gem5 pdb
* just track the lvimrc
* store CLI kernel config fragment inside buildlroot to avoid conflicts
* gem5: document m5 initparam
* readme: make a bunch of things awesomer
* readme: fix broken refs
* parsec-benchmark: update to 75d55ac446a43c47efb1044844a108c6c330184c
  Could not fetch otherwise.
* gem5: M5_OVERRIDE_PY_SOURCE

kernel_config/default

@@ -0,0 +1,125 @@
+# Misc.
+CONFIG_BLK_DEV_INITRD=y
+CONFIG_DEBUG_FS=y
+CONFIG_DYNAMIC_DEBUG=y
+CONFIG_MODULE_SRCVERSION_ALL=y
+CONFIG_OVERLAY_FS=y
+CONFIG_STRICT_DEVMEM=n
+
+# GDB debugging.
+CONFIG_DEBUG_INFO=y
+CONFIG_DEBUG_KERNEL=y
+CONFIG_GDB_SCRIPTS=y
+
+# KGDB
+CONFIG_CONSOLE_POLL=y
+CONFIG_KDB_CONTINUE_CATASTROPHIC=0
+CONFIG_KDB_DEFAULT_ENABLE=0x1
+CONFIG_KDB_KEYBOARD=y
+CONFIG_KGDB=y
+CONFIG_KGDB_KDB=y
+CONFIG_KGDB_LOW_LEVEL_TRAP=y
+CONFIG_KGDB_SERIAL_CONSOLE=y
+CONFIG_KGDB_TESTS=y
+CONFIG_KGDB_TESTS_ON_BOOT=n
+CONFIG_MAGIC_SYSRQ=y
+CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE=0x1
+CONFIG_SERIAL_KGDB_NMI=n
+
+# Non-static variables show up on /proc/kallsyms
+# https://stackoverflow.com/questions/20196636/does-kallsyms-have-all-the-symbol-of-kernel-functions/44614878#44614878
+CONFIG_KALLSYMS_ALL=y
+
+# /proc/config.gz
+CONFIG_IKCONFIG=y
+CONFIG_IKCONFIG_PROC=y
+
+# TODO make example.
+# This seems to allow userspace to create arbitrary configuration trees,
+# which kernel modules can then read and interpret.
+CONFIG_CONFIGFS_FS=y
+
+# Module.symvers in kernel tree and modules tree contains CRC of signatures.
+# TODO: I think the CRC are stored in the built kernel and module, and checked
+# at insmod, but bgrep did not find it in kernel image.
+# Does not show in /proc/kallyms either.
+CONFIG_MODVERSIONS=y
+
+# ftrace
+CONFIG_DYNAMIC_FTRACE=y
+CONFIG_FTRACE=y
+CONFIG_FTRACE_SYSCALLS=y
+CONFIG_FUNCTION_GRAPH_TRACER=y
+CONFIG_FUNCTION_PROFILER=y
+CONFIG_FUNCTION_TRACER=y
+CONFIG_HWLAT_TRACER=y
+CONFIG_IRQSOFF_TRACER=y
+CONFIG_SCHED_TRACER=y
+CONFIG_STACK_TRACER=y
+CONFIG_TRACER_SNAPSHOT=y
+
+# Process tracing.
+CONFIG_CONNECTOR=y
+CONFIG_PROC_EVENTS=y
+
+# 9P
+CONFIG_9P_FS=y
+CONFIG_9P_FS_POSIX_ACL=y
+CONFIG_9P_FS_SECURITY=y
+CONFIG_NETWORK_FILESYSTEMS=y
+CONFIG_NET_9P=y
+CONFIG_NET_9P_DEBUG=y
+CONFIG_NET_9P_VIRTIO=y
+# 9P needed for ARM. Not fully minimized, but so be it.
+CONFIG_PCI=y
+CONFIG_PCI_HOST_COMMON=y
+CONFIG_PCI_HOST_GENERIC=y
+CONFIG_VIRTIO_PCI=y
+CONFIG_VIRTIO_BLK=y
+
+# Misc
+CONFIG_DUMMY_IRQ=m
+CONFIG_FRAMEBUFFER_CONSOLE_ROTATION=y
+# Requirement for LOGO.
+CONFIG_FB=y
+CONFIG_LOGO=y
+
+## Networking
+
+# Will everything blow up?
+# https://superuser.com/questions/684005/how-does-one-permanently-disable-gnu-linux-networking/1255015#1255015
+#CONFIG_NET=n
+
+# If given, we can use QEMU 2.9.0 default x86 networking without any -net or -netdev options,
+# since E1000 is the default networking device as mentioned at:
+# https://en.wikibooks.org/w/index.php?title=QEMU/Networking&oldid=3268753
+#CONFIG_E1000=y
+
+## x86
+
+# https://stackoverflow.com/questions/20069620/print-kernels-page-table-entries
+# cat /sys/kernel/debug/kernel_page_tables
+CONFIG_X86_PTDUMP=y
+
+## UIO
+
+# All other UIO depend on this module.
+CONFIG_UIO=m
+
+# Generic platform devices.
+# https://yurovsky.github.io/2014/10/10/linux-uio-gpio-interrupt/
+CONFIG_UIO_DMEM_GENIRQ=m
+CONFIG_UIO_PDRV_GENIRQ=m
+
+# https://github.com/rumpkernel/wiki/wiki/Howto:-Accessing-PCI-devices-from-userspace
+# /sys/class/uio/
+# /sys/class/uio/uio0
+CONFIG_UIO_PCI_GENERIC=m
+
+## ARM
+
+# Like CONFIG_X86_PTDUMP for ARM.
+CONFIG_ARM64_PTDUMP=y
+
+# For record and replay.
+CONFIG_8139CP=y

kernel_config/display

@@ -0,0 +1,9 @@
+CONFIG_DRM=y
+
+## QEMU
+CONFIG_DRM_VIRTIO_GPU=y
+
+## gem5
+CONFIG_DRM_HDLCD=y
+# Only present in the gem5 fork.
+CONFIG_DRM_VIRT_ENCODER=y

kernel_config/gpio

@@ -0,0 +1,4 @@
+CONFIG_ARM_AMBA=y
+CONFIG_GPIOLIB=y
+CONFIG_GPIO_SYSFS=y
+CONFIG_GPIO_PL061=y

kernel_config/leds

@@ -0,0 +1,12 @@
+CONFIG_LEDS_CLASS=y
+CONFIG_LEDS_CLASS_FLASH=y
+CONFIG_LEDS_SYSCON=y
+CONFIG_LEDS_TRIGGERS=y
+CONFIG_LEDS_TRIGGER_BACKLIGHT=y
+CONFIG_LEDS_TRIGGER_CPU=y
+CONFIG_LEDS_TRIGGER_DEFAULT_ON=y
+CONFIG_LEDS_TRIGGER_GPIO=y
+CONFIG_LEDS_TRIGGER_HEARTBEAT=y
+CONFIG_LEDS_TRIGGER_ONESHOT=y
+CONFIG_LEDS_TRIGGER_TIMER=y
+CONFIG_NEW_LEDS=y

kernel_config/min

@@ -0,0 +1,25 @@
+# This file contains only configs which are required to boot all configurations and get a shell.
+
+## gem5 x86
+
+# CONFIG_INPUT_MOUSE is not set
+# CONFIG_INPUT_MOUSEDEV_PSAUX is not set
+
+## qemu aarch64
+
+# For some reason not selected by the Buildroot kernel config by default as it was for arm,
+# and pci modules fail to build. Not that we have PCI working on ARM anyways.
+CONFIG_PCI=y
+
+## gem5 aarch64
+
+# Minimal options required to run gem5 aarch64 in addition to QEMU's aarch64 setup.
+# Doing such a minimal boot made the gem5 boot 3x faster on the P51, which is awesome.
+CONFIG_ATA_PIIX=y
+CONFIG_PCI_HOST_GENERIC=y
+
+## qemu aarch64 ext2
+
+# Also requires gem5 aarch64 options.
+# Not needed for initrd / initramfs.
+CONFIG_VIRTIO_PCI=y