With the default kernel and thus with the build I have tested in
74ec94bfa2, we get an error during
modules_install:
make[2]: execvp: /nix/store/.../bin/bash: Argument list too long
I haven't noticed this build until I actually tried booting using this
kernel because make didn't fail here.
The reason this happens within Nix and probably didn't yet surface in
other distros is that programs only have a limited amount of memory
available for storing the environment and the arguments.
Environment variables however are quite common on Nix and thus we
stumble on problems like this way earlier - in this case Linux 4.8 - but
I have noticed this in 4.7-next as well already.
The fix is far from perfect and suffers performance overhead because we
now run grep for every *.mod file instead of passing all *.mod files
into one single invocation of grep.
But comparing the performance overhead (around 1s on my machine) with
the overall build time of the kernel I think the overhead really is
neglicible.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
Tested by only building the linux_testing attribute, but haven't yet
tested it in production.
I've also fixed the extraMeta.branch attribute.
Verified-with-PGP: ABAF 11C6 5A29 70B1 30AB E3C4 79BE 3E43 0041 1886
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
Previously, features.grsecurity wasn't actually set due to a bug in the
grsec builder. We now rely on the generic kernel builder to set features
from kernelPatches.
List of what to enable taken from https://lwn.net/Articles/672587/.
This doesn't change the resulting x86 configs, but is more useful for
other architectures. For instance, POSIX_MQUEUE is currently missing
on ARM.
glibc 2.24 deprecated readdir_r, breaking the perf build:
$ nix-build -A linuxPackages.perf
...
CC util/event.o
CC util/evlist.o
util/event.c: In function '__event__synthesize_thread':
util/event.c:448:2: error: 'readdir_r' is deprecated [-Werror=deprecated-declarations]
while (!readdir_r(tasks, &dirent, &next) && next) {
^
In file included from /nix/store/8ic0jwg3p5vcwx52k4781n987hmv0bks-glibc-2.24-dev/include/features.h:368:0,
from /nix/store/8ic0jwg3p5vcwx52k4781n987hmv0bks-glibc-2.24-dev/include/stdint.h:25,
from /nix/store/jsazxc1b86g2ww569ziwhhvkz8z43vjd-gcc-5.4.0/lib/gcc/x86_64-unknown-linux-gnu/5.4.0/include/stdint.h:9,
from /tmp/nix-build-perf-linux-4.4.19.drv-0/linux-4.4.19/tools/include/linux/types.h:6,
from util/event.c:1:
/nix/store/8ic0jwg3p5vcwx52k4781n987hmv0bks-glibc-2.24-dev/include/dirent.h:189:12: note: declared here
extern int __REDIRECT (readdir_r,
^
util/event.c: In function 'perf_event__synthesize_threads':
util/event.c:586:2: error: 'readdir_r' is deprecated [-Werror=deprecated-declarations]
while (!readdir_r(proc, &dirent, &next) && next) {
Fix by adding -Wno-error=deprecated-declarations compile flag.
Until we've made sure that most things actually work out of the box, we
need to give people a way of continuing to use the system without
completely disabling grsecurity.
Set sysctl kernel.pax.softmode=1 or boot with pax.softmode=1