kbuild: force all architectures except um to include mandatory-y

Currently, every arch/*/include/uapi/asm/Kbuild explicitly includes
the common Kbuild.asm file. Factor out the duplicated include directives
to scripts/Makefile.asm-generic so that no architecture would opt out
of the mandatory-y mechanism.

um is not forced to include mandatory-y since it is a very exceptional
case which does not support UAPI.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Documentation/kbuild/makefiles.txt

@@ -1274,7 +1274,7 @@ See subsequent chapter for the syntax of the Kbuild file.
 
 --- 7.4 mandatory-y
 
-	mandatory-y is essentially used by include/(uapi/)asm-generic/Kbuild.asm
+	mandatory-y is essentially used by include/(uapi/)asm-generic/Kbuild
 	to define the minimum set of ASM headers that all architectures must have.
 
 	This works like optional generic-y. If a mandatory header is missing

Makefile

@@ -1098,9 +1098,11 @@ asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
 
 PHONY += asm-generic uapi-asm-generic
 asm-generic: uapi-asm-generic
-	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm
+	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
+	generic=include/asm-generic
 uapi-asm-generic:
-	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm
+	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
+	generic=include/uapi/asm-generic
 
 PHONY += prepare-objtool
 prepare-objtool: $(objtool_target)

arch/alpha/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generated-y += unistd_32.h

arch/arc/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generic-y += kvm_para.h
 generic-y += ucontext.h

arch/arm/include/uapi/asm/Kbuild

 # SPDX-License-Identifier: GPL-2.0
-include include/uapi/asm-generic/Kbuild.asm
 
 generated-y += unistd-common.h
 generated-y += unistd-oabi.h

arch/arm64/include/uapi/asm/Kbuild

 # SPDX-License-Identifier: GPL-2.0
-include include/uapi/asm-generic/Kbuild.asm
 
 generic-y += kvm_para.h

arch/c6x/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generic-y += kvm_para.h
 generic-y += ucontext.h

arch/csky/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generic-y += ucontext.h

arch/h8300/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generic-y += kvm_para.h
 generic-y += ucontext.h

arch/hexagon/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generic-y += ucontext.h

arch/ia64/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generated-y += unistd_64.h
 generic-y += kvm_para.h

arch/m68k/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generated-y += unistd_32.h
 generic-y += kvm_para.h

arch/microblaze/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generated-y += unistd_32.h
 generic-y += kvm_para.h
 generic-y += ucontext.h

arch/mips/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generated-y += unistd_n32.h
 generated-y += unistd_n64.h
 generated-y += unistd_o32.h

arch/nds32/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generic-y += ucontext.h

arch/nios2/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generic-y += kvm_para.h
 generic-y += ucontext.h

arch/openrisc/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generic-y += kvm_para.h
 generic-y += ucontext.h

arch/parisc/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generated-y += unistd_32.h
 generated-y += unistd_64.h
 generic-y += kvm_para.h

arch/powerpc/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generated-y += unistd_32.h
 generated-y += unistd_64.h

arch/riscv/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm

arch/s390/include/uapi/asm/Kbuild

 # SPDX-License-Identifier: GPL-2.0
-include include/uapi/asm-generic/Kbuild.asm
 
 generated-y += unistd_32.h
 generated-y += unistd_64.h

arch/sh/include/uapi/asm/Kbuild

 # SPDX-License-Identifier: GPL-2.0
-include include/uapi/asm-generic/Kbuild.asm
 
 generated-y += unistd_32.h
 generic-y += kvm_para.h

arch/sparc/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generated-y += unistd_32.h
 generated-y += unistd_64.h

arch/unicore32/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generic-y += kvm_para.h
 generic-y += ucontext.h

arch/x86/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generated-y += unistd_32.h
 generated-y += unistd_64.h
 generated-y += unistd_x32.h

arch/xtensa/include/uapi/asm/Kbuild

-include include/uapi/asm-generic/Kbuild.asm
-
 generated-y += unistd_32.h
 generic-y += kvm_para.h

include/asm-generic/Kbuild

+# SPDX-License-Identifier: GPL-2.0
+#
+# asm headers that all architectures except um should have
+# (This file is not included when SRCARCH=um since UML borrows several
+# asm headers from the host architecutre.)

include/uapi/asm-generic/Kbuild.asm → include/uapi/asm-generic/Kbuild

+# SPDX-License-Identifier: GPL-2.0
 #
 # Headers that are mandatory in usr/include/asm/
-#
+# (This file is not included when SRCARCH=um since UML does not support UAPI.)
+
 mandatory-y += auxvec.h
 mandatory-y += bitsperlong.h
 mandatory-y += bpf_perf_event.h

scripts/Makefile.asm-generic

@@ -12,6 +12,11 @@ all:
 src := $(subst /generated,,$(obj))
 -include $(src)/Kbuild
 
+# $(generic)/Kbuild lists mandatory-y. Exclude um since it is a special case.
+ifneq ($(SRCARCH),um)
+include $(generic)/Kbuild
+endif
+
 include scripts/Kbuild.include
 
 redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y))