kconfig: check for pkg-config on make {menu,n,g,x}config

Each of 'make {menu,n,g,x}config' uses (needs) pkg-config to make sure
that other required files are present and to determine build flags
settings, but none of these check that pkg-config itself is present.
Add a check for all 4 of these targets and update
Documentation/process/changes.rst to mention 'pkg-config'.

Fixes kernel bugzilla #77511:
https://bugzilla.kernel.org/show_bug.cgi?id=77511

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Bjørn Forsman <bjorn.forsman@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

2 files changed, 9 insertions, 0 deletions

diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index a3ac2c91331c..49edb9cc9410 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -215,6 +215,7 @@ $(obj)/zconf.tab.o: $(obj)/zconf.lex.c
 
 # check if necessary packages are available, and configure build flags
 define filechk_conf_cfg
+        $(CONFIG_SHELL) $(srctree)/scripts/kconfig/check-pkgconfig.sh; \
         $(CONFIG_SHELL) $<
 endef
 
diff --git a/scripts/kconfig/check-pkgconfig.sh b/scripts/kconfig/check-pkgconfig.sh
new file mode 100644
index 000000000000..7a1c40bfb58c
--- /dev/null
+++ b/scripts/kconfig/check-pkgconfig.sh
@@ -0,0 +1,8 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# Check for pkg-config presence
+
+if [ -z $(command -v pkg-config) ]; then
+        echo "'make *config' requires 'pkg-config'. Please install it." 1>&2
+        exit 1
+fi