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KLOADER(4)                   Device Drivers Manual                  KLOADER(4)

NAME
     kloader - in-kernel bootloader

SYNOPSIS
     options KLOADER
     options KLOADER_KERNEL_PATH="\"/netbsd\""

DESCRIPTION
     The kloader is the in-kernel bootloader for platforms that do not have a
     proper firmware.

     Some platforms supported by NetBSD do not have a firmware that can boot
     the NetBSD kernel.  Examples are game consoles (dreamcast and
     playstation2 ports), and handhelds (hpcarm, hpcmips, and hpcsh ports).
     On such platforms the bootloader is usually a host program that runs
     under the native OS.  This means that rebooting NetBSD is a lengthy
     process of booting into the native OS first, launching the bootloader
     program, and finally booting NetBSD again.  This problem is addressed by
     kloader, which allows the currently running kernel to serve as a
     bootloader for the kernel being booted, thus avoiding the burden of
     booting into the native OS first.

     When kloader is configured into the kernel, a call to reboot(2) causes
     the kloader to load the new kernel into memory, and arrange for control
     to be passed to the new kernel -- just like a standalone bootloader does.
     The new kernel then boots in the ordinary manner.

SEE ALSO
     reboot(2), boot(8), reboot(8)

HISTORY
     kloader first appeared in NetBSD 1.6.

BUGS
     kloader ignores howto and bootstr arguments passed to the reboot(2)
     system call, and reboots the system with the previous boot settings.

     kloader doesn't support booting compressed kernels.

     The hpcarm port doesn't support kloader yet.

NetBSD 10.99                     April 3, 2004                    NetBSD 10.99