This is the last LTS version buildable using GCC 4.0.x. The next one,
version 4.19, requires at least GCC 4.6.
Fortunately, this is also the first version of the Linux kernel
without firmware blobs being included in /firmware, so the FSFLA
deblob scripts aren't needed anymore to ensure a fully auditable
kernel - the 3 remaining drivers that do include blobs masquerading
as source code are removed via a patch, avoiding all the other side
effects of the deblob scripts.
This doesn't compromise the trustworthiness of the bootstrapped
environment, since all the other drivers deblob would remove use
the firmware loader mechanism, which does nothing when the actual
firmware blobs aren't installed on the system separately. Features
dependent on firmware still won't work, but many drivers that load
firmware do so only optionally. This includes r8169, the driver for
the Realtek gigabit NICs found on many x86 motherboards.
This kernel is considerably larger than 4.9.10, and we build more
of it (including drivers that would previously get stripped away by
the deblob script, such as r8169), so to accommodate that, Fiwix
initrd size is increased by 64MiB, while lowering kexec space by
the same amount to ensure enough userspace memory available in Fiwix.
Fiwix's maximum open file count is also bumped from 1.5K to 2.5K.
The Documentation folder is deleted before build, to further save
space in the ramdisk.
We spawn a shell:
- When Bash is first built, on tty2. This shell uses the old Bash,
so interactive mode needs to be emulated using redirection. Thus,
entering commands needs to be done using Enter followed by Ctrl+D,
and certain redirection features are unavailable.
- After moving the system to disk, on tty2. Old Bash, same limitations.
- After 2nd Bash is built, on tty3. This is a fully functional shell.
This is disabled in chroot-like bootstrap modes, or when -i is not set.
This was removed as part of the simplify refactor, severely slowing
down qemu and bare-metal builds. Restoring it brings us back to the
same build times that we saw before the refactor.
With this, finalize_fhs.sh can be rerun as needed, e.g. when rebooting.
Also, the preferred nameserver will persist after DHCP.
Thanks to devtmpfs, we no longer need to manage /dev once Linux is up.
These are implemented as dummy jumps with a script that just exits
with success. Since this script will be sourced, rather than called,
this causes the bootstrap process to exit at that point.
The breakpoints are conditional on INTERNAL_CI (we check for "pass1"
because that's the only pass when script-generator runs, but the
resulting effect is that each pass only bootstraps its own part of
the manifest).
