Re: [gentoo-dev] [PATCH 2/4] kernel-build.eclass: sanity check the prepared kernel's release string

[Andrew Nowa Ammerlaan <andrewammerlaan@gentoo.org>]

Part of https://github.com/gentoo/gentoo/pull/37327

 From 021915604b90ee45332dc373f401e52afa832370 Mon Sep 17 00:00:00 2001
From: James Calligeros <jcalligeros99@gmail.com>
Date: Sat, 29 Jun 2024 01:55:12 +0000
Subject: [PATCH] kernel-build.eclass: sanity check the prepared kernel's
  release string

Previously, this was only checked by kernel-install_pkg_preinst(). This
means that the entire kernel would have to be built and stripped before
we knew if we had built the correct kernel or not.

Duplicate this check in kernel-build_src_configure() so that we don't waste
time and energy building an incorrectly-versioned kernel.

Signed-off-by: James Calligeros <jcalligeros99@gmail.com>
---
  eclass/kernel-build.eclass | 13 +++++++++++++
  1 file changed, 13 insertions(+)

diff --git a/eclass/kernel-build.eclass b/eclass/kernel-build.eclass
index 7d4b98ac027d9..408837c4c57a7 100644
--- a/eclass/kernel-build.eclass
+++ b/eclass/kernel-build.eclass
@@ -239,6 +239,19 @@ kernel-build_src_configure() {
  		local relfile=${WORKDIR}/build/include/config/kernel.release
  		KV_FULL=$(<"${relfile}") || die
  	fi
+
+	# Make sure we are about to build the correct kernel
+	if [[ ${PV} != *9999 ]]; then
+		local expected_ver=$(dist-kernel_PV_to_KV "${PV}")
+
+		if [[ ${KV_FULL} != ${expected_ver}* ]]; then
+			eerror "Kernel version does not match PV!"
+			eerror "Source version: ${KV_FULL}"
+			eerror "Expected (PV*): ${expected_ver}*"
+			eerror "Please ensure you are applying the correct patchset."
+			die "Kernel version mismatch: got ${KV_FULL}, expected ${expected_ver}*"
+		fi
+	fi
  }

  # @FUNCTION: kernel-build_src_compile