From feec5e1f74f5b735c0c5c02ec70673db1334173f Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@chromium.org>
Date: Thu, 31 Aug 2023 12:13:39 -0700
Subject: [PATCH] kbuild: Show marked Kconfig fragments in "help"
Currently the Kconfig fragments in kernel/configs and arch/*/configs
that aren't used internally aren't discoverable through "make help",
which consists of hard-coded lists of config fragments. Instead, list
all the fragment targets that have a "# Help: " comment prefix so the
targets can be generated dynamically.
Add logic to the Makefile to search for and display the fragment and
comment. Add comments to fragments that are intended to be direct targets.
Signed-off-by: Kees Cook <keescook@chromium.org>
Co-developed-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---
Makefile | 1 -
arch/arm/configs/dram_0x00000000.config | 1 +
arch/arm/configs/dram_0xc0000000.config | 1 +
arch/arm/configs/dram_0xd0000000.config | 1 +
arch/arm/configs/lpae.config | 1 +
arch/arm64/configs/virt.config | 1 +
arch/powerpc/configs/disable-werror.config | 1 +
arch/powerpc/configs/security.config | 4 +++-
arch/riscv/configs/32-bit.config | 1 +
arch/riscv/configs/64-bit.config | 1 +
arch/s390/configs/btf.config | 1 +
arch/s390/configs/kasan.config | 1 +
arch/x86/Makefile | 4 ----
kernel/configs/debug.config | 2 ++
kernel/configs/kvm_guest.config | 1 +
kernel/configs/nopm.config | 2 ++
kernel/configs/rust.config | 1 +
kernel/configs/x86_debug.config | 1 +
kernel/configs/xen.config | 2 ++
scripts/kconfig/Makefile | 15 ++++++++++++---
20 files changed, 34 insertions(+), 9 deletions(-)
diff --git a/Makefile b/Makefile
index e21bf66af6fd3..23cd62a5ff059 100644
--- a/Makefile
+++ b/Makefile
@@ -1552,7 +1552,6 @@ help:
@echo ' mrproper - Remove all generated files + config + various backup files'
@echo ' distclean - mrproper + remove editor backup and patch files'
@echo ''
- @echo 'Configuration targets:'
@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
@echo ''
@echo 'Other generic targets:'
diff --git a/arch/arm/configs/dram_0x00000000.config b/arch/arm/configs/dram_0x00000000.config
index db96dcb420ceb..8803a0f58343c 100644
--- a/arch/arm/configs/dram_0x00000000.config
+++ b/arch/arm/configs/dram_0x00000000.config
@@ -1 +1,2 @@
+# Help: DRAM base at 0x00000000
CONFIG_DRAM_BASE=0x00000000
diff --git a/arch/arm/configs/dram_0xc0000000.config b/arch/arm/configs/dram_0xc0000000.config
index 343d5333d973d..aab8f864686b5 100644
--- a/arch/arm/configs/dram_0xc0000000.config
+++ b/arch/arm/configs/dram_0xc0000000.config
@@ -1 +1,2 @@
+# Help: DRAM base at 0xc0000000
CONFIG_DRAM_BASE=0xc0000000
diff --git a/arch/arm/configs/dram_0xd0000000.config b/arch/arm/configs/dram_0xd0000000.config
index 61ba7045f8a13..4aabce4ea3d46 100644
--- a/arch/arm/configs/dram_0xd0000000.config
+++ b/arch/arm/configs/dram_0xd0000000.config
@@ -1 +1,2 @@
+# Help: DRAM base at 0xd0000000
CONFIG_DRAM_BASE=0xd0000000
diff --git a/arch/arm/configs/lpae.config b/arch/arm/configs/lpae.config
index a6d6f7ab3c01a..1ab94da8345d3 100644
--- a/arch/arm/configs/lpae.config
+++ b/arch/arm/configs/lpae.config
@@ -1,2 +1,3 @@
+# Help: Enable Large Physical Address Extension mode
CONFIG_ARM_LPAE=y
CONFIG_VMSPLIT_2G=y
diff --git a/arch/arm64/configs/virt.config b/arch/arm64/configs/virt.config
index 6865d54e68f88..c47c36f8f67b7 100644
--- a/arch/arm64/configs/virt.config
+++ b/arch/arm64/configs/virt.config
@@ -1,3 +1,4 @@
+# Help: Virtualization guest
#
# Base options for platforms
#
diff --git a/arch/powerpc/configs/disable-werror.config b/arch/powerpc/configs/disable-werror.config
index 6ea12a12432c9..7776b91da37f1 100644
--- a/arch/powerpc/configs/disable-werror.config
+++ b/arch/powerpc/configs/disable-werror.config
@@ -1 +1,2 @@
+# Help: Disable -Werror
CONFIG_PPC_DISABLE_WERROR=y
diff --git a/arch/powerpc/configs/security.config b/arch/powerpc/configs/security.config
index 1c91a35c6a733..0d54e29e2cdfc 100644
--- a/arch/powerpc/configs/security.config
+++ b/arch/powerpc/configs/security.config
@@ -1,3 +1,5 @@
+# Help: Common security options for PowerPC builds
+
# This is the equivalent of booting with lockdown=integrity
CONFIG_SECURITY=y
CONFIG_SECURITYFS=y
@@ -12,4 +14,4 @@ CONFIG_INIT_ON_ALLOC_DEFAULT_ON=y
# UBSAN bounds checking is very cheap and good for hardening
CONFIG_UBSAN=y
-# CONFIG_UBSAN_MISC is not set
\ No newline at end of file
+# CONFIG_UBSAN_MISC is not set
diff --git a/arch/riscv/configs/32-bit.config b/arch/riscv/configs/32-bit.config
index f6af0f708df4a..16ee163847b44 100644
--- a/arch/riscv/configs/32-bit.config
+++ b/arch/riscv/configs/32-bit.config
@@ -1,3 +1,4 @@
+# Help: Build a 32-bit image
CONFIG_ARCH_RV32I=y
CONFIG_32BIT=y
# CONFIG_PORTABLE is not set
diff --git a/arch/riscv/configs/64-bit.config b/arch/riscv/configs/64-bit.config
index 313edc554d84c..d872a2d533f20 100644
--- a/arch/riscv/configs/64-bit.config
+++ b/arch/riscv/configs/64-bit.config
@@ -1,2 +1,3 @@
+# Help: Build a 64-bit image
CONFIG_ARCH_RV64I=y
CONFIG_64BIT=y
diff --git a/arch/s390/configs/btf.config b/arch/s390/configs/btf.config
index 39227b4511aff..eb7f84f5925cf 100644
--- a/arch/s390/configs/btf.config
+++ b/arch/s390/configs/btf.config
@@ -1 +1,2 @@
+# Help: Enable BTF debug info
CONFIG_DEBUG_INFO_BTF=y
diff --git a/arch/s390/configs/kasan.config b/arch/s390/configs/kasan.config
index 700a8b25c3ffc..84c2b551e9927 100644
--- a/arch/s390/configs/kasan.config
+++ b/arch/s390/configs/kasan.config
@@ -1,3 +1,4 @@
+# Help: Enable KASan for debugging
CONFIG_KASAN=y
CONFIG_KASAN_INLINE=y
CONFIG_KASAN_VMALLOC=y
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index fdc2e3abd6152..c4b2a8a19fc83 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -335,9 +335,5 @@ define archhelp
echo ' bzdisk/fdimage*/hdimage/isoimage also accept:'
echo ' FDARGS="..." arguments for the booted kernel'
echo ' FDINITRD=file initrd for the booted kernel'
- echo ''
- echo ' kvm_guest.config - Enable Kconfig items for running this kernel as a KVM guest'
- echo ' xen.config - Enable Kconfig items for running this kernel as a Xen guest'
- echo ' x86_debug.config - Enable tip tree debugging options for testing'
endef
diff --git a/kernel/configs/debug.config b/kernel/configs/debug.config
index e8db8d9386617..4722b998a3245 100644
--- a/kernel/configs/debug.config
+++ b/kernel/configs/debug.config
@@ -1,3 +1,5 @@
+# Help: Debugging for CI systems and finding regressions
+#
# The config is based on running daily CI for enterprise Linux distros to
# seek regressions on linux-next builds on different bare-metal and virtual
# platforms. It can be used for example,
diff --git a/kernel/configs/kvm_guest.config b/kernel/configs/kvm_guest.config
index 208481d910903..d0877063d925c 100644
--- a/kernel/configs/kvm_guest.config
+++ b/kernel/configs/kvm_guest.config
@@ -1,3 +1,4 @@
+# Help: Bootable as a KVM guest
CONFIG_NET=y
CONFIG_NET_CORE=y
CONFIG_NETDEVICES=y
diff --git a/kernel/configs/nopm.config b/kernel/configs/nopm.config
index 81ff078635769..ebfdc3d8aa9ad 100644
--- a/kernel/configs/nopm.config
+++ b/kernel/configs/nopm.config
@@ -1,3 +1,5 @@
+# Help: Disable Power Management
+
CONFIG_PM=n
CONFIG_SUSPEND=n
CONFIG_HIBERNATION=n
diff --git a/kernel/configs/rust.config b/kernel/configs/rust.config
index 38a7c5362c9cf..2c6e001a72849 100644
--- a/kernel/configs/rust.config
+++ b/kernel/configs/rust.config
@@ -1 +1,2 @@
+# Help: Enable Rust
CONFIG_RUST=y
diff --git a/kernel/configs/x86_debug.config b/kernel/configs/x86_debug.config
index 6fac5b405334e..35f48671b8d5c 100644
--- a/kernel/configs/x86_debug.config
+++ b/kernel/configs/x86_debug.config
@@ -1,3 +1,4 @@
+# Help: Debugging options for tip tree testing
CONFIG_X86_DEBUG_FPU=y
CONFIG_LOCK_STAT=y
CONFIG_DEBUG_VM=y
diff --git a/kernel/configs/xen.config b/kernel/configs/xen.config
index 436f806aa1ed0..6878b9a49be8d 100644
--- a/kernel/configs/xen.config
+++ b/kernel/configs/xen.config
@@ -1,3 +1,5 @@
+# Help: Bootable as a Xen guest
+#
# global stuff - these enable us to allow some
# of the not so generic stuff below for xen
CONFIG_PARAVIRT=y
diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index af1c96198f491..4eee155121a8b 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -93,11 +93,13 @@ endif
%_defconfig: $(obj)/conf
$(Q)$< $(silent) --defconfig=arch/$(SRCARCH)/configs/$@ $(Kconfig)
-configfiles=$(wildcard $(srctree)/kernel/configs/$@ $(srctree)/arch/$(SRCARCH)/configs/$@)
+configfiles = $(wildcard $(srctree)/kernel/configs/$(1) $(srctree)/arch/$(SRCARCH)/configs/$(1))
+all-config-fragments = $(call configfiles,*.config)
+config-fragments = $(call configfiles,$@)
%.config: $(obj)/conf
- $(if $(call configfiles),, $(error No configuration exists for this target on this architecture))
- $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh -m .config $(configfiles)
+ $(if $(config-fragments),, $(error $@ fragment does not exists on this architecture))
+ $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh -m .config $(config-fragments)
$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
PHONY += tinyconfig
@@ -115,6 +117,7 @@ clean-files += tests/.cache
# Help text used by make help
help:
+ @echo 'Configuration targets:'
@echo ' config - Update current config utilising a line-oriented program'
@echo ' nconfig - Update current config utilising a ncurses menu based program'
@echo ' menuconfig - Update current config utilising a menu based program'
@@ -141,6 +144,12 @@ help:
@echo ' default value without prompting'
@echo ' tinyconfig - Configure the tiniest possible kernel'
@echo ' testconfig - Run Kconfig unit tests (requires python3 and pytest)'
+ @echo ''
+ @echo 'Configuration topic targets:'
+ @$(foreach f, $(all-config-fragments), \
+ if help=$$(grep -m1 '^# Help: ' $(f)); then \
+ printf ' %-25s - %s\n' '$(notdir $(f))' "$${help#*: }"; \
+ fi;)
# ===========================================================================
# object files used by all kconfig flavours
--
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