From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lwn.net header.i=@lwn.net header.b="l8tkBJCf" Received: from ms.lwn.net (ms.lwn.net [IPv6:2600:3c01:e000:3a1::42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 99E81B3; Fri, 17 Nov 2023 08:17:59 -0800 (PST) Received: from localhost (unknown [75.104.68.237]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ms.lwn.net (Postfix) with ESMTPSA id A3D712F3; Fri, 17 Nov 2023 16:17:57 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 ms.lwn.net A3D712F3 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lwn.net; s=20201203; t=1700237879; bh=mFiWwbKnYfvY3qTIUsUeh4zZYBejY47lhESfh35MH8g=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=l8tkBJCfW+xaqYswMUfTtjOw9T5AO/2mQFbZpmr2TYszVaIJwfXyarkk2GaUNUQ7K GVV8ZUL33tpFF16LeI2y7wBq75NDaLEMBdwyMCVsZRBO0VjiYKMMul/sopB0bt3y1d O39/v9voBBW83F6Isvk7fcwQhbmBEOS78sE/9AJrlmhbnrTyIFOq2uWlj/961jmPCX wrFKbEBxSD1dQnYcdzyutfqjhZ+vKVKDOkJgLnFVXDBcrxSJproeCQCSHyIWU1KQY3 1Czc/C7BShhTO1yV+3j00FchICtnj7gBC+jsC6OVspSBUScT0k/6hVtpuAyFAzY2sN PyNtUDX4XG6mQ== From: Jonathan Corbet To: Hunter Chasens Cc: linux-doc@vger.kernel.org, ardb@kernel.org, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, Hunter Chasens Subject: Re: [PATCH v3 1/2] docs: admin-guide: Update bootloader and installation instructions In-Reply-To: <20231114030208.30479-1-hunter.chasens18@ncf.edu> References: <20231114030208.30479-1-hunter.chasens18@ncf.edu> Date: Fri, 17 Nov 2023 09:17:50 -0700 Message-ID: <87wmugwdzl.fsf@meer.lwn.net> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain Hunter Chasens writes: > Updates the bootloader and installation instructions in > admin-guide/README.rst to align with modern practices. > > Details of Changes: > > - Added guidance on using EFISTUB for UEFI/EFI systems. > - Noted that LILO is no longer in active development and provides > alternatives. > - Kept LILO instructions but marked as Legacy LILO Instructions. > Suggest removal in future patch. > > Signed-off-by: Hunter Chasens > --- > Documentation/admin-guide/README.rst | 69 ++++++++++++++++++---------- > 1 file changed, 45 insertions(+), 24 deletions(-) These seem like good changes in general. Not too many of us are using LILO these days... > diff --git a/Documentation/admin-guide/README.rst b/Documentation/admin-guide/README.rst > index 9a969c0157f1..ad53f4245379 100644 > --- a/Documentation/admin-guide/README.rst > +++ b/Documentation/admin-guide/README.rst > @@ -262,9 +262,11 @@ Compiling the kernel > - Make sure you have at least gcc 5.1 available. > For more information, refer to :ref:`Documentation/process/changes.rst `. > > - - Do a ``make`` to create a compressed kernel image. It is also > - possible to do ``make install`` if you have lilo installed to suit the > - kernel makefiles, but you may want to check your particular lilo setup first. > + - Do a ``make`` to create a compressed kernel image. It is also possible to do > + ``make install`` if you have lilo installed or if your distribution has an > + install script recognised by the kernel's installer. Most popular > + distributions will have a recognized install script. You may want to > + check your distribution's setup first. Is there a reason to not just suggest looking for installkernel by name? This seems more obscure than it needs to be. > To do the actual install, you have to be root, but none of the normal > build should require that. Don't take the name of root in vain. > @@ -301,32 +303,51 @@ Compiling the kernel > image (e.g. .../linux/arch/x86/boot/bzImage after compilation) > to the place where your regular bootable kernel is found. > > - - Booting a kernel directly from a floppy without the assistance of a > - bootloader such as LILO, is no longer supported. > - > - If you boot Linux from the hard drive, chances are you use LILO, which > - uses the kernel image as specified in the file /etc/lilo.conf. The > - kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or > - /boot/bzImage. To use the new kernel, save a copy of the old image > - and copy the new image over the old one. Then, you MUST RERUN LILO > - to update the loading map! If you don't, you won't be able to boot > - the new kernel image. > - > - Reinstalling LILO is usually a matter of running /sbin/lilo. > - You may wish to edit /etc/lilo.conf to specify an entry for your > - old kernel image (say, /vmlinux.old) in case the new one does not > - work. See the LILO docs for more information. > - > - After reinstalling LILO, you should be all set. Shutdown the system, > + - Booting a kernel directly from non-volatile memory (e.g. a hard drive) "non-volatile memory" has a bit of a different meaning that could confuse things here. "a storage device" perhaps? > + without the assistance of a bootloader such as LILO or GRUB, is no longer > + supported in BIOS (non-EFI systems). On UEFI/EFI systems, however, you can > + use EFISTUB which allows the motherboard to boot directly to the kernel. > + On modern workstations and desktops, it's generally recommended to use a > + bootloader as difficulties can arise with multiple kernels and secure boot. > + For more details on EFISTUB, > + see :ref:`Documentation/admin-guide/efi-stub.rst `. You can just say "see Documentation/admin-guide/efi-stub.rst" here without the extra markup. > + - It's important to note that as of 2016 LILO (LInux LOader) is no longer in > + active development, though as it was extremely popular, it often comes up > + in documentation. Popular alternatives include GRUB2, rEFInd, Syslinux, > + systemd-boot, or EFISTUB. For various reasons, it's not recommended to use > + software that's no longer in active development. I honestly wonder if we need to mention LILO at all here. > + - Chances are your distribution includes an install script and running > + ``make install`` will be all that's needed. Should that not be the case > + you'll have to identify your bootloader and reference its documentation or > + configure your EFI. Again, name the script directly. > +Legacy LILO Instructions > +------------------------ > + > + > + - If you use LILO the kernel images are specified in the file /etc/lilo.conf. > + The kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or > + /boot/bzImage. To use the new kernel, save a copy of the old image and copy > + the new image over the old one. Then, you MUST RERUN LILO to update the > + loading map! If you don't, you won't be able to boot the new kernel image. > + > + - Reinstalling LILO is usually a matter of running /sbin/lilo. You may wish > + to edit /etc/lilo.conf to specify an entry for your old kernel image > + (say, /vmlinux.old) in case the new one does not work. See the LILO docs > + for more information. > + > + - After reinstalling LILO, you should be all set. Shutdown the system, > reboot, and enjoy! > > - If you ever need to change the default root device, video mode, > - etc. in the kernel image, use your bootloader's boot options > - where appropriate. No need to recompile the kernel to change > - these parameters. > + - If you ever need to change the default root device, video mode, etc. in the > + kernel image, use your bootloader's boot options where appropriate. No need > + to recompile the kernel to change these parameters. > > - Reboot with the new kernel and enjoy. If it were me I'd probably take this out too...but somebody is bound to complain. Thanks, jon