[gentoo-commits] data/gentoo-news:master commit in: 2024-05-17-dracut-ext-kmods/

[gentoo-commits] data/gentoo-news:master commit in: 2024-05-17-dracut-ext-kmods/

[Andrew Ammerlaan]

commit:     c64a05c51a237c6011b0d57d3739cb27e1927f3d
Author:     Andrew Ammerlaan <andrewammerlaan <AT> gentoo <DOT> org>
AuthorDate: Fri May 17 08:19:31 2024 +0000
Commit:     Andrew Ammerlaan <andrewammerlaan <AT> gentoo <DOT> org>
CommitDate: Fri May 17 08:19:31 2024 +0000
URL:        https://gitweb.gentoo.org/data/gentoo-news.git/commit/?id=c64a05c5

2024-05-17-dracut-ext-kmods: add news item

Signed-off-by: Andrew Ammerlaan <andrewammerlaan <AT> gentoo.org>

 .../2024-05-17-dracut-ext-kmods.en.txt             | 106 +++++++++++++++++++++
 1 file changed, 106 insertions(+)

diff --git a/2024-05-17-dracut-ext-kmods/2024-05-17-dracut-ext-kmods.en.txt b/2024-05-17-dracut-ext-kmods/2024-05-17-dracut-ext-kmods.en.txt
new file mode 100644
index 0000000..ff2bdf6
--- /dev/null
+++ b/2024-05-17-dracut-ext-kmods/2024-05-17-dracut-ext-kmods.en.txt
@@ -0,0 +1,106 @@
+Title: Changes to dracut kernel module/microcode handling
+Author: Andrew Ammerlaan <andrewammerlaan@gentoo.org>
+Posted: 2024-05-17
+Revision: 1
+News-Item-Format: 2.0
+Display-If-Installed: sys-kernel/dracut
+Display-If-Installed: virtual/dist-kernel
+Display-If-Installed: sys-kernel/linux-firmware
+Display-If-Installed: sys-firmware/intel-microcode
+
+
+Impact
+====================
+
+Several changes were made regarding out-of-tree kernel modules, CPU
+microcode, and how these are handled in initial RAM file systems
+(initramfs) generated by sys-kernel/dracut for distribution kernels.
+Depending on the local Dracut and USE flag configuration, some
+configuration adjustments may be required as a result of these changes.
+
+Background (the problem)
+====================
+
+Previously Dracut implicitly included all out-of-tree kernel modules
+it could find. This leads to several problems:
+- It unnecessarily increases the size of the initramfs
+- It creates a bit of a mess when using distribution kernels, consider
+    the following:
+        1) Distribution kernel is upgraded
+        2) Initramfs for the new kernel is generated, it does not include
+            any out-of-tree kernel modules.
+        3) Portage triggers rebuild of the out-of-tree kernel modules
+        4) If zfs is installed, its rebuild will trigger an initramfs
+            re-installation. Otherwise no rebuild is triggered.
+    Problem: What is and is not included in the initramfs is now
+    ambiguous. It depends on the emerge order of the kernel modules
+    when zfs is used. And will completely change if at some later stage
+    regeneration of the initramfs is triggered manually via e.g.:
+        emerge --config sys-kernel/gentoo-kernel
+    As a result, Dracut's "--reproducible" setting is not working. And
+    the functionality of the initramfs may change (seemingly) at random.
+
+Background (the fix)
+====================
+
+Several things have been changed:
+- Out-of-tree kernel modules installed by portage are explicitly omitted
+    from the initramfs generated by Dracut by default.
+- Packages that install a kernel module for which it might make sense to
+    have it in the initramfs, have gained the "initramfs" USE flag. When
+    this flag is enabled, Dracut is instructed to include the installed
+    kernel modules. Packages for which it is essential that its kernel
+    modules are included in the initramfs have this new flag enabled
+    by default.
+- When distribution kernels are used (USE=dist-kernel), and a module
+    that should be in the initramfs is installed (USE=initramfs) the
+    initramfs is always re-generated.
+- The packages installing CPU microcode (sys-kernel/linux-firmware
+    and sys-firmware/intel-microcode) have been adjusted to mirror the
+    above changes for out-of-tree kernel modules. Both packages
+    have gained the "dist-kernel" USE flag, and the "initramfs" flag is
+    now enabled by default. When both flags are enabled, Dracut is
+    configured to include the installed microcode in the initramfs, and
+    then the initramfs is regenerated. When the "dist-kernel" flag is
+    disabled, the "initramfs" flag behaves as it previously did.
+
+User Action Required
+====================
+
+Users should double check two things:
+1) Please ensure that you are *not* globally enabling or disabling
+    the "initramfs" USE flag. Enabling it globally might result in an
+    unnecessarily large initramfs. Disabling it globally might result
+    in missing functionality in the initramfs. Which could lead to boot
+    failure if, for example, the zfs module is missing while the root
+    partition is a zfs.
+2) Any add_drivers, or omit_drivers lines in /etc/dracut.conf or
+    /etc/dracut.conf.d/* may override the Dracut configuration snippets
+    installed by the kernel module packages in
+    /usr/lib/dracut/dracut.conf.d.  Please review your Dracut
+    configuration files to ensure that you are not unintentionally
+    overriding the settings set by Portage.
+
+Frequently Asked Questions
+====================
+
+A package installing a kernel module I would like in my initramfs has
+not gained the "initramfs" USE flag. How do I proceed?
+
+    Please report a new bug on bugs.gentoo.org, requesting that the
+    package maintainer consider adding support to the package for
+    including the modules in the initramfs. In the meantime you can
+    locally override the configuration provided by the package (see
+    below). Note though that when distribution kernels are used,
+    regeneration of the initramfs must be triggered manually via e.g.:
+        emerge --config sys-kernel/gentoo-kernel
+
+How do I override the provided Dracut configuration snippets to
+include/exclude a custom list of modules?
+
+    To override the provided configuration snippet, create a new file
+    /etc/dracut.conf.d/10-PACKAGENAME.conf, replacing PACKAGENAME with
+    the name of the package providing the module. Add to this file:
+        omit_drivers+=" my list of drivers to omit "
+    and/or
+        add_drivers+=" my list of drivers to include "

[gentoo-commits] data/gentoo-news:master commit in: 2024-05-17-dracut-ext-kmods/

[Andrew Ammerlaan]

commit:     3557467d15bb3e848c1a73e70dfaa786a2de29d9
Author:     Andrew Ammerlaan <andrewammerlaan <AT> gentoo <DOT> org>
AuthorDate: Sun May 19 15:12:36 2024 +0000
Commit:     Andrew Ammerlaan <andrewammerlaan <AT> gentoo <DOT> org>
CommitDate: Sun May 19 15:12:36 2024 +0000
URL:        https://gitweb.gentoo.org/data/gentoo-news.git/commit/?id=3557467d

2024-05-17-dracut-ext-kmods: clarify the non-dracut/dist-kernel case

Signed-off-by: Andrew Ammerlaan <andrewammerlaan <AT> gentoo.org>

 .../2024-05-17-dracut-ext-kmods.en.txt             | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/2024-05-17-dracut-ext-kmods/2024-05-17-dracut-ext-kmods.en.txt b/2024-05-17-dracut-ext-kmods/2024-05-17-dracut-ext-kmods.en.txt
index ff2bdf6..af58a63 100644
--- a/2024-05-17-dracut-ext-kmods/2024-05-17-dracut-ext-kmods.en.txt
+++ b/2024-05-17-dracut-ext-kmods/2024-05-17-dracut-ext-kmods.en.txt
@@ -1,7 +1,7 @@
 Title: Changes to dracut kernel module/microcode handling
 Author: Andrew Ammerlaan <andrewammerlaan@gentoo.org>
 Posted: 2024-05-17
-Revision: 1
+Revision: 2
 News-Item-Format: 2.0
 Display-If-Installed: sys-kernel/dracut
 Display-If-Installed: virtual/dist-kernel
@@ -18,6 +18,7 @@ microcode, and how these are handled in initial RAM file systems
 Depending on the local Dracut and USE flag configuration, some
 configuration adjustments may be required as a result of these changes.
 
+
 Background (the problem)
 ====================
 
@@ -40,6 +41,7 @@ it could find. This leads to several problems:
     As a result, Dracut's "--reproducible" setting is not working. And
     the functionality of the initramfs may change (seemingly) at random.
 
+
 Background (the fix)
 ====================
 
@@ -64,10 +66,12 @@ Several things have been changed:
     then the initramfs is regenerated. When the "dist-kernel" flag is
     disabled, the "initramfs" flag behaves as it previously did.
 
-User Action Required
+
+User Action Required (Dracut and/or Distribution Kernel users)
 ====================
 
-Users should double check two things:
+Users of sys-kernel/dracut and/or Distribution Kernels should double
+check two things:
 1) Please ensure that you are *not* globally enabling or disabling
     the "initramfs" USE flag. Enabling it globally might result in an
     unnecessarily large initramfs. Disabling it globally might result
@@ -81,6 +85,18 @@ Users should double check two things:
     configuration files to ensure that you are not unintentionally
     overriding the settings set by Portage.
 
+
+User Action Required (other users)
+====================
+
+Other users may wish to disable the "initramfs" USE flag on
+sys-kernel/linux-firmware and/or sys-firmware/intel-microcode
+if they already have other mechanisms in place for updating the CPU
+microcode (such as kernel built-in CPU microcode). Users who do not
+use sys-kernel/dracut or Distribution Kernels can safely disable
+the "initramfs" USE flag globally.
+
+
 Frequently Asked Questions
 ====================