On Sep 24, 9:14am, Reinoud Zandijk wrote:
} Subject: Re: "Boot this kernel once" functionality? (amd64)
} On Wed, Sep 16, 2020 at 12:09:43PM +0200, Martin Husemann wrote:
} > On Wed, Sep 16, 2020 at 12:05:26PM +0200, Anthony Mallet wrote:
} > > I was also wondering if it would be possible to pass arguments to the
} > > primary or secondary bootloader via reboot(2) and the boothowto
} > > flags. But this doesn't seem doable. Right?
} >
} > This works fine on e.g. sparc*; I can do: shutdown -b netbsd.t -r now
} >
} > and it will pass "netbsd.t" as boot argument to the firmware, which passes
} > it on to the bootloader and then it boots /netbsd.t once.
}
} In shutdown(8) I read that the arguments are passed to reboot(8) and that is
} mentioned in kloader(4) so I guess its using that mechanism.
}
} As for amd64, it would be great if I could boot a kernel once. It could
} simplify testing out a new kernel. Not that a few lines of boot.cfg can't do
} that but still.
}
} > I don't know if there is enough of a persistent environment for UEFI boots
} > (I would guess there is), and probably no easy way for BIOS boot.
}
} I could imagine some BIOS/UEFI wiping all DRAM on reboot for security reasons.
UEFI has the concept of persistent variable storage (key/value
store). See Section 8.2 "Variable Services" of the UEFI spec.
}-- End of excerpt from Reinoud Zandijk
