This enables a few features that should be useful and safe (they're
all used by the default Ubuntu kernel config), in particular zswap,
wakelocks, kernel load address randomization, userfaultfd (useful for
QEMU), paravirtualized spinlocks and automatic process group
scheduling.
Also removes some configuration conditional on kernel versions that we
no longer support.
The config option DEVPTS_MULTIPLE_INSTANCES now no longer exists since
torvalds/linux@eedf265aa0.
Built successfully on my Hydra instance:
https://headcounter.org/hydra/log/r4n6sv0zld0aj65r7l494757s2r8w8sr-linux-4.7-rc6.drv
Verified unpacked tarball with GnuPG:
ABAF 11C6 5A29 70B1 30AB E3C4 79BE 3E43 0041 1886
gpg: Signature made Mon 04 Jul 2016 08:13:05 AM CEST
gpg: using RSA key 79BE3E4300411886
gpg: Good signature from "Linus Torvalds <torvalds@linux-foundation.org>"
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
Per my own testing, the NixOS grsecurity kernel works both as a
KVM-based virtualisation host and guest; there appears to be no good
reason to making these conditional on `features.grsecurity`.
More generally, it's unclear what `features.grsecurity` *means*. If
someone configures a grsecurity kernel in such a fashion that it breaks
KVM support, they should know to disable KVM themselves.
This was presumably set for grsecurity compatibility, but now appears
redundant. Grsecurity does not expect nor require /dev/kmem to be
present and so it makes little sense to continue making its inclusion in
the standard kernel dependent on grsecurity.
More generally, given the large number of possible grsecurity
configurations, it is unclear what `features.grsecurity` even
*means* and its use should be discouraged.
- Enable BPF_SYSCALL and BPF_EVENTS
- Build modules for NET_CLS_BPF and NET_ACT_BPF
With these config options we can leverage the full potential of BPF for
tracing and instrumenting Linux systems, for example using
libraries/tools like those provided by the bcc project.
This hopefully fixes intermittent initrd failures where udevd cannot
create a Unix domain socket:
machine# running udev...
machine# error getting socket: Address family not supported by protocol
machine# error initializing udev control socket
machine# error getting socket: Address family not supported by protocol
The "unix" kernel module is supposed to be loaded automatically, and
clearly that works most of the time, but maybe there is a race
somewhere. In any case, no sane person would run a kernel without Unix
domain sockets, so we may as well make it builtin.
http://hydra.nixos.org/build/30001448
Systemd dropped support in 207 (would be nice if configure failed with a bad flag),
so all this does is add an annoying delay if firmware can't be found by the kernel
Namespace support is required by the `unshare` tool used in
`nixos-install`. It's enabled by the x86 defconfig, but not by
e.g. multi_v7_defconfig. So enable it here so that `nixos-install`
can work on ARM.
KVM_COMPAT apparently enables 32-bit compability syscalls for KVM, and
as such can be enabled only on a 64-bit system.
Resolves error http://hydra.nixos.org/build/23014132/nixlog/1/raw:
GOT: #
GOT: # configuration written to .config
GOT: #
GOT: make[1]: Leaving directory '/tmp/nix-build-linux-config-4.0.5.drv-0/build'
GOT: make: Leaving directory '/tmp/nix-build-linux-config-4.0.5.drv-0/linux-4.0.5'
unused option: KVM_COMPAT
builder for ‘/nix/store/7kskdvmzs116f1fm55ghm0crjniw9q0a-linux-config-4.0.5.drv’ failed with exit code 255
IKCONFIG must be enabled so IKCONFIG_PROC can be set. On x86 IKCONFIG
gets implicitly enabled by kernelAutoModules in platforms.nix. But ARM
doesn't use kernelAutoModules, so IKCONFIG_PROC won't get enabled
without this patch.
Commit 159fed47bc (nixos/grub: Fix video display on efi) changed BIOS
systems to start in non-text mode as well. Enable FB_VESA to get a
framebuffer console on BIOS systems. Change FRAMEBUFFER_CONSOLE to 'y'
instead of the default 'm' to so the user doesn't need to manually load
the fbcon module anymore.
Other distros have similar defaults, at least on Arch:
CONFIG_FB_VESA=y
CONFIG_FRAMEBUFFER_CONSOLE=y
and on Ubuntu (12.04):
CONFIG_FB_VESA=m
CONFIG_FRAMEBUFFER_CONSOLE=y
Fixes#8139
