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Fix date format in manual pages.
2017-06-03 19:27:30 +00:00
.Dd October 5, 2015
Add manual pages.
2015-10-05 22:32:45 +00:00
.Dt KERNEL 7
.Os
.Sh NAME
.Nm kernel
.Nd operating system kernel
.Sh SYNOPSIS
.Pa /boot/sortix.bin
Refactor kernel command line parsing.
2017-02-25 22:25:53 +00:00
.Op Fl \-no-random-seed
.Op Fl \-
.Op Ar init ...
Add manual pages.
2015-10-05 22:32:45 +00:00
.Sh DESCRIPTION
.Pa /boot/sortix.bin
is the operating system
.Nm kernel .
It initializes and manages the hardware to provide a multitasking computing
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
2017-02-15 21:56:28 +00:00
environment.
The kernel is a
Add manual pages.
2015-10-05 22:32:45 +00:00
.Xr multiboot 7
compatible executable loaded by the bootloader along with a companion
.Xr initrd 7
that contains a userland.
.Pp
Refactor kernel command line parsing.
2017-02-25 22:25:53 +00:00
The kernel extracts the initrd into the initial kernel memory root filesystem.
The specified
.Ar init
program is invoked with the given arguments, defaulting to the
Add manual pages.
2015-10-05 22:32:45 +00:00
.Xr init 8
Refactor kernel command line parsing.
2017-02-25 22:25:53 +00:00
at
.Pa /sbin/init
if
.Ar init
is not specified.
If the
.Nm init
is to receive any argument starting with a dash, first pass the
.Fl \-
delimiter to stop kernel option parsing.
The computer is powered off if the
.Nm init
process exits 0, rebooted if it exits 1,
Print an kernel error rather than panicing if init(8) exits abnormally. This avoids the misimpression that a kernel bug happened and it avoids clearing the screen of potentially useful information about an init(8) crash.
2017-05-21 20:20:28 +00:00
halted with an complaint about an
.Nm init
fatality if it exits 2, and halted with a complaint about an unexpected exit code
otherwise.
Add manual pages.
2015-10-05 22:32:45 +00:00
.Pp
The options are as follows:
.Bl -tag -width "12345678"
Seed kernel entropy with randomness from the previous boot. The bootloader will now load the /boot/random.seed file if it exists, in which case the kernel will use it as the initial kernel entropy. The kernel warns if no random seed was loaded, unless the --no-random-seed option was given. This option is used for live environments that inherently have no prior secret state. The kernel initializes its entropy pool from the random seed as of the first things, so randomness is available very early on. init(8) will emit a fresh /boot/random.seed file on boot to avoid the same entropy being used twice. init(8) also writes out /boot/random.seed on system shutdown where the system has the most entropy. init(8) will warn if writing the file fails, except if /boot is a real-only filesystem, and keeping such state is impossible. The system administrator is then responsible for ensuring the bootloader somehow passes a fresh random seed on the next boot. /boot/random.seed must be owned by the root user and root group and must have file permissions 600 to avoid unprivileged users can read it. The file is passed to the kernel by the bootloader as a multiboot module with the command line --random-seed. If no random seed is loaded, the kernel attempts a poor quality fallback where it seeds the kernel arc4random(3) continuously with the current time. The timing variance may provide some effective entropy. There is no real kernel entropy gathering yet. The read of the CMOS real time clock is moved to an early point in the kernel boot, so the current time is available as fallback entropy. The kernel access of the random seed module is supposed to be infallible and happens before the kernel log is set up, but there is not yet a failsafe API for mapping single pages in the early kernel. sysupgrade(8) creates /boot/random.seed if it's absent as a temporary compatibility measure for people upgrading from the 1.0 release. The GRUB port will need to be upgraded with support for /boot/random.seed in the 10_sortix script. Installation with manual bootloader configuration will need to load the random seed with the --random-seed command line. With GRUB, this can be done with: module /boot/random.seed --random-seed
2016-08-20 00:27:33 +00:00
.It Fl \-no-random-seed
Don't warn if no random seed file was loaded by the bootloader (usually from
.Pa /boot/random.seed ) .
This option is useful for live environments where this situation is unavoidable.
Add manual pages.
2015-10-05 22:32:45 +00:00
.El
.Sh SEE ALSO
.Xr initrd 7 ,
.Xr init 8