From d469acd4d505f9ea76dbead86c58274fa5711fd6 Mon Sep 17 00:00:00 2001
From: Emil Velikov <emil.l.velikov@gmail.com>
Date: Thu, 22 Aug 2024 17:04:21 +0100
Subject: [PATCH] build: remove linux/module.h check

We include the header for the UAPI MODULE_INIT_* constants, while we
also provide them locally.

At a glance, at least Arch and Alpine build kmod without the uapi
header, so just drop the check and ifndef guards all together.

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Lucas De Marchi <lucas.de.marchi@gmail.com>
Link: https://github.com/kmod-project/kmod/pull/86
Signed-off-by: Lucas De Marchi <lucas.de.marchi@gmail.com>
---
 configure.ac             |  3 ---
 libkmod/libkmod-module.c |  3 ---
 shared/missing.h         | 26 +++++++++++---------------
 3 files changed, 11 insertions(+), 21 deletions(-)

diff --git a/configure.ac b/configure.ac
index 62781470..5396436d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -55,9 +55,6 @@ AC_CHECK_MEMBERS([struct stat.st_mtim], [], [], [#include <sys/stat.h>])
 # not desired here
 AC_CHECK_DECLS_ONCE([[strndupa], [basename]], [], [], [[#include <string.h>]])
 
-# Check kernel headers
-AC_CHECK_HEADERS_ONCE([linux/module.h])
-
 AC_MSG_CHECKING([whether _Static_assert() is supported])
 AC_COMPILE_IFELSE(
 	[AC_LANG_SOURCE([[_Static_assert(1, "Test");]])],
diff --git a/libkmod/libkmod-module.c b/libkmod/libkmod-module.c
index c23159fb..9cfc8017 100644
--- a/libkmod/libkmod-module.c
+++ b/libkmod/libkmod-module.c
@@ -21,9 +21,6 @@
 #include <sys/syscall.h>
 #include <sys/types.h>
 #include <sys/wait.h>
-#ifdef HAVE_LINUX_MODULE_H
-#include <linux/module.h>
-#endif
 
 #include <shared/util.h>
 
diff --git a/shared/missing.h b/shared/missing.h
index 137c9a9f..86caf80a 100644
--- a/shared/missing.h
+++ b/shared/missing.h
@@ -3,21 +3,17 @@
 #include <unistd.h>
 #include <sys/syscall.h>
 
-#ifdef HAVE_LINUX_MODULE_H
-#include <linux/module.h>
-#endif
-
-#ifndef MODULE_INIT_IGNORE_MODVERSIONS
-# define MODULE_INIT_IGNORE_MODVERSIONS 1
-#endif
-
-#ifndef MODULE_INIT_IGNORE_VERMAGIC
-# define MODULE_INIT_IGNORE_VERMAGIC 2
-#endif
-
-#ifndef MODULE_INIT_COMPRESSED_FILE
-# define MODULE_INIT_COMPRESSED_FILE 4
-#endif
+/*
+ * Macros pulled from linux/module.h, to avoid pulling the header.
+ *
+ * In practise very few people have it installed and distros do not install the
+ * relevant package during their build.
+ *
+ * Values are UAPI, so they cannot change.
+ */
+#define MODULE_INIT_IGNORE_MODVERSIONS 1
+#define MODULE_INIT_IGNORE_VERMAGIC 2
+#define MODULE_INIT_COMPRESSED_FILE 4
 
 #ifndef __NR_finit_module
 # warning __NR_finit_module missing - kmod might not work correctly
-- 
2.47.3