Sometimes we have situations when we want linux/foo.h include asm/bar.h if the latter exists; one example is includes of asm/syscall_wrapper.h. Right now there are two ways to do that: 1) ARCH_HAS_BAR_H, explicitly selected by architectures that have asm/bar.h and include guarded by #ifdef CONFIG_ARCH_HAS_BAR_H 2) include/asm-default/bar.h, either empty or with something like #define __ARCH_HAS_NO_BAR_H, with mandatory-y += bar.h in include/asm-generic/Kbuild and unconditional includes of asm/bar.h, possibly followed by #ifdef __ARCH_HAS_NO_BAR_H ... #endif However, kconfig could do (1) without selects - something like bool ARCH_HAS_BAR_H def_bool $(header-exists,bar.h) Does anybody see problems with the patch below? Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> --- diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 1652a9800ebe..277437f329ce 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -42,7 +42,6 @@ config ARM64 select ARCH_HAS_STRICT_MODULE_RWX select ARCH_HAS_SYNC_DMA_FOR_DEVICE select ARCH_HAS_SYNC_DMA_FOR_CPU - select ARCH_HAS_SYSCALL_WRAPPER select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_HAS_VM_GET_PAGE_PROT diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 91c0b80a8bf0..86e905b8462c 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -78,7 +78,6 @@ config S390 select ARCH_HAS_SET_MEMORY select ARCH_HAS_STRICT_KERNEL_RWX select ARCH_HAS_STRICT_MODULE_RWX - select ARCH_HAS_SYSCALL_WRAPPER select ARCH_HAS_UBSAN_SANITIZE_ALL select ARCH_HAS_VDSO_DATA select ARCH_HAVE_NMI_SAFE_CMPXCHG diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index be0b95e51df6..64592d027a0d 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -92,7 +92,6 @@ config X86 select ARCH_HAS_STRICT_KERNEL_RWX select ARCH_HAS_STRICT_MODULE_RWX select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE - select ARCH_HAS_SYSCALL_WRAPPER select ARCH_HAS_UBSAN_SANITIZE_ALL select ARCH_HAS_VM_GET_PAGE_PROT select ARCH_HAS_DEBUG_WX diff --git a/init/Kconfig b/init/Kconfig index c7900e8975f1..ce88397c4e46 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -2257,4 +2257,4 @@ config ARCH_HAS_SYNC_CORE_BEFORE_USERMODE # kernel/time/posix-stubs.c. All these overrides need to be available in # <asm/syscall_wrapper.h>. config ARCH_HAS_SYSCALL_WRAPPER - def_bool n + def_bool $(header-exists,syscall_wrapper.h) diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include index 0496efd6e117..465bb836f82a 100644 --- a/scripts/Kconfig.include +++ b/scripts/Kconfig.include @@ -23,6 +23,10 @@ success = $(if-success,$(1),y,n) # Return n if <command> exits with 0, y otherwise failure = $(if-success,$(1),n,y) +# $(header-exists,<header>) +# Return y if arch/$(ARCH)/include/asm/<header> exists, n otherwise +header-exists = $(success,test -e $(srctree)/arch/$(ARCH)/include/asm/$(1)) + # $(cc-option,<flag>) # Return y if the compiler supports <flag>, n otherwise cc-option = $(success,mkdir .tmp_$$$$; trap "rm -rf .tmp_$$$$" EXIT; $(CC) -Werror $(CLANG_FLAGS) $(1) -c -x c /dev/null -o .tmp_$$$$/tmp.o)
