Commit
5318321d367c ("samples: disable CONFIG_SAMPLES for UML") used
a big hammer to fix the build errors under the samples/ directory.
Only some samples actually include uapi headers from usr/include.
Introduce CONFIG_HEADERS_INSTALL since 'depends on HEADERS_INSTALL' is
clearer than 'depends on !UML'. If this option is enabled, uapi headers
are installed before starting directory descending.
I added 'depends on HEADERS_INSTALL' to per-sample CONFIG options.
This allows UML to compile some samples.
$ make ARCH=um allmodconfig samples/
[ snip ]
CC [M] samples/configfs/configfs_sample.o
CC [M] samples/kfifo/bytestream-example.o
CC [M] samples/kfifo/dma-example.o
CC [M] samples/kfifo/inttype-example.o
CC [M] samples/kfifo/record-example.o
CC [M] samples/kobject/kobject-example.o
CC [M] samples/kobject/kset-example.o
CC [M] samples/trace_events/trace-events-sample.o
CC [M] samples/trace_printk/trace-printk.o
AR samples/vfio-mdev/built-in.a
AR samples/built-in.a
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
targets := vmlinux
-# Some samples need headers_install.
-samples: headers_install
-
# The actual objects are generated when descending,
# make sure no implicit rule kicks in
$(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
$(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi dst=include HDRCHECK=1
+ifdef CONFIG_HEADERS_INSTALL
+prepare: headers_install
+endif
+
ifdef CONFIG_HEADERS_CHECK
all: headers_check
endif
PHONY += /
/: ./
-samples/: headers_install
%/: prepare FORCE
$(Q)$(MAKE) KBUILD_MODULES=1 $(build)=$(build-dir)
CONFIG_DEBUG_INFO=y
CONFIG_STRIP_ASM_SYMS=y
CONFIG_DEBUG_FS=y
+CONFIG_HEADERS_INSTALL=y
CONFIG_HEADERS_CHECK=y
CONFIG_DEBUG_SECTION_MISMATCH=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_INFO_DWARF4=y
CONFIG_GDB_SCRIPTS=y
CONFIG_READABLE_ASM=y
+CONFIG_HEADERS_INSTALL=y
CONFIG_HEADERS_CHECK=y
CONFIG_DEBUG_SECTION_MISMATCH=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_NLS_ISO8859_15=m
CONFIG_NLS_UTF8=m
CONFIG_DEBUG_FS=y
+CONFIG_HEADERS_INSTALL=y
CONFIG_HEADERS_CHECK=y
CONFIG_MAGIC_SYSRQ=y
# CONFIG_DEBUG_BUGVERBOSE is not set
CONFIG_NLS_ISO8859_1=m
CONFIG_NLS_ISO8859_15=m
CONFIG_NLS_UTF8=m
+CONFIG_HEADERS_INSTALL=y
CONFIG_HEADERS_CHECK=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_KERNEL=y
CONFIG_NLS_ISO8859_15=m
CONFIG_NLS_UTF8=m
CONFIG_DEBUG_FS=y
+CONFIG_HEADERS_INSTALL=y
CONFIG_HEADERS_CHECK=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_MUTEXES=y
CONFIG_NLS_KOI8_U=m
CONFIG_NLS_UTF8=y
CONFIG_DEBUG_FS=y
+CONFIG_HEADERS_INSTALL=y
CONFIG_HEADERS_CHECK=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_KERNEL=y
CONFIG_NLS_KOI8_U=m
CONFIG_DEBUG_INFO=y
CONFIG_UNUSED_SYMBOLS=y
+CONFIG_HEADERS_INSTALL=y
CONFIG_HEADERS_CHECK=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_KERNEL=y
CONFIG_FRAME_WARN=1024
CONFIG_READABLE_ASM=y
CONFIG_UNUSED_SYMBOLS=y
+CONFIG_HEADERS_INSTALL=y
CONFIG_HEADERS_CHECK=y
CONFIG_DEBUG_SECTION_MISMATCH=y
CONFIG_MAGIC_SYSRQ=y
If unsure, say N.
+config HEADERS_INSTALL
+ bool "Install uapi headers to usr/include"
+ depends on !UML
+ help
+ This option will install uapi headers (headers exported to user-space)
+ into the usr/include directory for use during the kernel build.
+ This is unneeded for building the kernel itself, but needed for some
+ user-space program samples. It is also needed by some features such
+ as uapi header sanity checks.
+
config HEADERS_CHECK
bool "Run sanity checks on uapi headers when building 'all'"
- depends on !UML
+ depends on HEADERS_INSTALL
help
- This option will extract the user-visible kernel headers when
- building the 'all' target, and will run basic sanity checks on them to
- ensure that exported files do not attempt to include files which
- were not exported, etc.
+ This option will run basic sanity checks on uapi headers when
+ building the 'all' target, for example, ensure that they do not
+ attempt to include files which were not exported, etc.
If you're making modifications to header files which are
relevant for userspace, say 'Y', and check the headers
# SPDX-License-Identifier: GPL-2.0-only
menuconfig SAMPLES
bool "Sample kernel code"
- depends on !UML
help
You can build and test sample kernel code here.
config SAMPLE_CONNECTOR
tristate "Build connector sample -- loadable modules only"
- depends on CONNECTOR && m
+ depends on CONNECTOR && HEADERS_INSTALL && m
help
When enabled, this builds both a sample kernel module for
the connector interface and a user space tool to communicate
with it.
See also Documentation/connector/connector.txt
+config SAMPLE_HIDRAW
+ bool "hidraw sample"
+ depends on HEADERS_INSTALL
+
+config SAMPLE_PIDFD
+ bool "pidfd sample"
+ depends on HEADERS_INSTALL
+
config SAMPLE_SECCOMP
bool "Build seccomp sample code"
- depends on SECCOMP_FILTER
+ depends on SECCOMP_FILTER && HEADERS_INSTALL
help
Build samples of seccomp filters using various methods of
BPF filter construction.
config SAMPLE_VFS
bool "Build example programs that use new VFS system calls"
+ depends on HEADERS_INSTALL
help
Build example userspace programs that use new VFS system calls such
as mount API and statx(). Note that this is restricted to the x86
obj-$(CONFIG_SAMPLE_ANDROID_BINDERFS) += binderfs/
obj-$(CONFIG_SAMPLE_CONFIGFS) += configfs/
obj-$(CONFIG_SAMPLE_CONNECTOR) += connector/
-subdir-y += hidraw
+subdir-$(CONFIG_SAMPLE_HIDRAW) += hidraw
obj-$(CONFIG_SAMPLE_HW_BREAKPOINT) += hw_breakpoint/
obj-$(CONFIG_SAMPLE_KDB) += kdb/
obj-$(CONFIG_SAMPLE_KFIFO) += kfifo/
obj-$(CONFIG_SAMPLE_KOBJECT) += kobject/
obj-$(CONFIG_SAMPLE_KPROBES) += kprobes/
obj-$(CONFIG_SAMPLE_LIVEPATCH) += livepatch/
-subdir-y += pidfd
+subdir-$(CONFIG_SAMPLE_PIDFD) += pidfd
obj-$(CONFIG_SAMPLE_QMI_CLIENT) += qmi/
obj-$(CONFIG_SAMPLE_RPMSG_CLIENT) += rpmsg/
subdir-$(CONFIG_SAMPLE_SECCOMP) += seccomp