add package: kernel-modules-hook-hardlinks

kernel-modules-hook-hardlinks/10-linux-modules-post.hook

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+[Trigger]
+Operation = Remove
+Type = Path
+Target = usr/lib/modules/*/vmlinuz
+
+[Action]
+Description = Restoring Linux kernel modules...
+When = PostTransaction
+Exec = /usr/share/libalpm/scripts/linux-modules-restore
+NeedsTargets

kernel-modules-hook-hardlinks/10-linux-modules-pre.hook

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+[Trigger]
+Operation = Install
+Operation = Remove
+Type = Path
+Target = usr/lib/modules/*/vmlinuz
+
+[Action]
+Description = Saving Linux kernel modules directory (hardlinks)...
+When = PreTransaction
+Exec = /usr/share/libalpm/scripts/linux-modules-save
+NeedsTargets

kernel-modules-hook-hardlinks/PKGBUILD

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+# Maintainer: Max Gautier <mg+archlinux@max.gautier.name>
+# Contributor: Artoria Pendragon <saber-nyan@ya.ru>
+_pkgname=kernel-modules-hook
+pkgname=${_pkgname}-hardlinks
+pkgver=0.2.3
+pkgrel=1
+pkgdesc="Keeps your system fully functional after a kernel upgrade"
+arch=('any')
+provides=("$_pkgname")
+url="https://github.com/VannTen/$_pkgname"
+license=('GPL3')
+source=("linux-modules-cleanup.conf"
+        "10-linux-modules-post.hook"
+        "10-linux-modules-pre.hook"
+        "linux-modules-restore"
+        "linux-modules-save"
+)
+sha256sums=('950f851eba08dac4d0b93ff62b3fb16ddacd4f8ebb98a2435f80bf05f2ea5a29'
+            'fc4d53dec520c80fe97dfda65b238c7d678e7ef26aaebffc5b43f924477ea4f4'
+            '087e5ed70b2fc512d814fbded9e873955b1da5b6bf1e31975174d704ad143156'
+            '28b995f6ea62899620d43d71e542bfc3432ad3ce90a6582f4ded1173fe8c0837'
+            '5d9092689d9baa3d8e5ac65ae92d1c201e23c4ef42c99d131f9465c99d6505ef')
+
+package() {
+	install -Dm644 'linux-modules-cleanup.conf' "${pkgdir}/usr/lib/tmpfiles.d/linux-modules-cleanup.conf"
+	install -Dm644 10-linux-modules-{pre,post}.hook -t "${pkgdir}/usr/share/libalpm/hooks/"
+	install -Dm755 linux-modules-{save,restore} -t "${pkgdir}/usr/share/libalpm/scripts/"
+}

kernel-modules-hook-hardlinks/README.md

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+# kernel-modules-hook
+
+This is an alpm hook for Archlinux (or other pacman-based distribution) to keep the kernel modules of the running kernel available during a kernel upgrade.
+
+It relies on hardlinks and bind mount for saving and restoring, and systemd-tmpfiles for cleanup.
+
+## Installation
+
+### Archlinux
+[AUR](https://aur.archlinux.org/packages/kernel-modules-hook-hardlinks/)
+
+Use your AUR helper of choise, or use makepkg.

kernel-modules-hook-hardlinks/linux-modules-cleanup.conf

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+R! /usr/lib/modules/running-kernel
+r /usr/lib/modules/*

kernel-modules-hook-hardlinks/linux-modules-restore

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+#!/bin/bash -e
+
+kver=$(uname -r)
+while read -r line; do
+    # We only care about the running kernel
+    if [[ "$line" == usr/lib/modules/$kver/vmlinuz && -d "${line/$kver/running-kernel}" ]];then
+        mount --mkdir --bind --options ro /usr/lib/modules/{running-kernel,$kver}
+        # Mounting read-only since the only modification here should be unmounting
+        # when rebooting or reinstalling the running kernel
+    fi
+done

kernel-modules-hook-hardlinks/linux-modules-save

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+#!/bin/bash -e
+
+kver=$(uname -r)
+while read -r line; do
+    # We only care about the running kernel
+    if [[ "$line" == "usr/lib/modules/$kver/vmlinuz" ]];then
+        if mountpoint --nofollow --quiet ${line%vmlinuz};then
+            # Mount point is already present
+            # This means we already ran that hook during 'remove case'
+            #
+            # Remove the mount so we can reinstall the kernel
+            umount ${line%vmlinuz}
+        elif [[ -f "$line" && ! -d "/usr/lib/modules/running-kernel/" ]];then
+            # Kernel install is present and we do not have a copy
+            #
+            # This is the removal case, so we save the kernel
+            mkdir /usr/lib/modules/running-kernel
+            cp --archive --link /usr/lib/modules/{$kver}/{kernel,modules*} \
+                /usr/lib/modules/running-kernel/
+        fi
+        # If we are re-removing the running kernel, (after removing + reinstalling),
+        # we already have a backup and this hook is a no-op
+    fi
+done