From: Benjamin Berg benjamin.berg@intel.com

The define mapped to __attribute__((__unused__)) instead of using __used__.

Fixes: e58e871becec ("tools/lib/lockdep: Remove private kernel headers") Signed-off-by: Benjamin Berg benjamin.berg@intel.com --- tools/include/linux/compiler.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/include/linux/compiler.h b/tools/include/linux/compiler.h index 33411ca0cc90..b2c40621d441 100644 --- a/tools/include/linux/compiler.h +++ b/tools/include/linux/compiler.h @@ -127,7 +127,7 @@ #endif

#ifndef __used -# define __used __attribute__((__unused__)) +# define __used __attribute__((__used__)) #endif

#ifndef __packed

From: Benjamin Berg benjamin.berg@intel.com

Using the kernel headers directly from the userspace parts of UML is problematic. Switch to use the headers from the tools/include subdirectory instead. These contain stripped down versions that work well for UML and only relatively small adjustments are needed to make it work.

This adds two symlinks so that the userspace code can still find asm-offsets.h and user_constants.h. Other than that, some includes are moved into USER_CFLAGS instead of handling them in Makefile.rules.

Signed-off-by: Benjamin Berg benjamin.berg@intel.com --- arch/um/Makefile | 11 +++++++---- arch/um/include/shared/generated/asm-offsets.h | 1 + arch/um/include/shared/generated/user_constants.h | 1 + arch/um/include/shared/init.h | 2 +- arch/um/include/shared/user.h | 5 ----- arch/um/kernel/skas/stub.c | 1 + arch/um/kernel/skas/stub_exe.c | 4 ++-- arch/um/os-Linux/skas/process.c | 6 ++---- arch/um/os-Linux/start_up.c | 4 ++-- arch/um/scripts/Makefile.rules | 2 +- arch/x86/um/Makefile | 6 ++++-- arch/x86/um/user-offsets.c | 1 - 12 files changed, 22 insertions(+), 22 deletions(-) create mode 120000 arch/um/include/shared/generated/asm-offsets.h create mode 120000 arch/um/include/shared/generated/user_constants.h

diff --git a/arch/um/Makefile b/arch/um/Makefile index 7be0143b5ba3..a3f27d791cc0 100644 --- a/arch/um/Makefile +++ b/arch/um/Makefile @@ -70,10 +70,13 @@ KBUILD_AFLAGS += $(ARCH_INCLUDE)

USER_CFLAGS = $(patsubst $(KERNEL_DEFINES),,$(patsubst -I%,,$(KBUILD_CFLAGS))) \ $(ARCH_INCLUDE) $(MODE_INCLUDE) $(filter -I%,$(CFLAGS)) \ - -D_FILE_OFFSET_BITS=64 -idirafter $(srctree)/include \ - -idirafter $(objtree)/include -D__KERNEL__ -D__UM_HOST__ \ - -include $(srctree)/include/linux/compiler-version.h \ - -include $(srctree)/include/linux/kconfig.h + -idirafter $(srctree)/tools/include \ + -D__UM_HOST__ \ + -include $(srctree)/tools/include/linux/compiler.h \ + -include $(srctree)/tools/include/linux/kconfig.h \ + -include $(srctree)/include/generated/autoconf.h \ + -include $(srctree)/include/linux/kern_levels.h \ + -include $(srctree)/$(ARCH_DIR)/include/shared/user.h

#This will adjust *FLAGS accordingly to the platform. include $(srctree)/$(ARCH_DIR)/Makefile-os-Linux diff --git a/arch/um/include/shared/generated/asm-offsets.h b/arch/um/include/shared/generated/asm-offsets.h new file mode 120000 index 000000000000..22fd929dbac7 --- /dev/null +++ b/arch/um/include/shared/generated/asm-offsets.h @@ -0,0 +1 @@ +../../../../../include/generated/asm-offsets.h \ No newline at end of file diff --git a/arch/um/include/shared/generated/user_constants.h b/arch/um/include/shared/generated/user_constants.h new file mode 120000 index 000000000000..5f67c190ec09 --- /dev/null +++ b/arch/um/include/shared/generated/user_constants.h @@ -0,0 +1 @@ +../../../../../include/generated/user_constants.h \ No newline at end of file diff --git a/arch/um/include/shared/init.h b/arch/um/include/shared/init.h index 1a659e2e8cc3..d201705bedb3 100644 --- a/arch/um/include/shared/init.h +++ b/arch/um/include/shared/init.h @@ -41,7 +41,7 @@ typedef int (*initcall_t)(void); typedef void (*exitcall_t)(void);

-#include <linux/compiler_types.h> +#define __section(section) __attribute__((__section__(section)))

/* These are for everybody (although not all archs will actually discard it in modules) */ diff --git a/arch/um/include/shared/user.h b/arch/um/include/shared/user.h index 139eb78a4767..c9b853e1282f 100644 --- a/arch/um/include/shared/user.h +++ b/arch/um/include/shared/user.h @@ -16,13 +16,8 @@ */ #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))

-/* This is to get size_t and NULL */ -#ifndef __UM_HOST__ #include <linux/types.h> -#else #include <stddef.h> -#include <sys/types.h> -#endif

extern void panic(const char *fmt, ...) __attribute__ ((format (printf, 1, 2))); diff --git a/arch/um/kernel/skas/stub.c b/arch/um/kernel/skas/stub.c index 67cab46a602c..6c9bb1511ea2 100644 --- a/arch/um/kernel/skas/stub.c +++ b/arch/um/kernel/skas/stub.c @@ -5,6 +5,7 @@

#include <sysdep/stub.h>

+#include <linux/init.h> #include <linux/futex.h> #include <sys/socket.h> #include <errno.h> diff --git a/arch/um/kernel/skas/stub_exe.c b/arch/um/kernel/skas/stub_exe.c index cbafaa684e66..0563838c01d1 100644 --- a/arch/um/kernel/skas/stub_exe.c +++ b/arch/um/kernel/skas/stub_exe.c @@ -4,8 +4,8 @@ #include <asm/unistd.h> #include <sysdep/stub.h> #include <stub-data.h> -#include <linux/filter.h> -#include <linux/seccomp.h> +#include <uapi/linux/filter.h> +#include <uapi/linux/seccomp.h> #include <generated/asm-offsets.h>

void _start(void); diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c index 78f48fa9db8b..8ad7e863af97 100644 --- a/arch/um/os-Linux/skas/process.c +++ b/arch/um/os-Linux/skas/process.c @@ -29,9 +29,7 @@ #include <sysdep/stub.h> #include <sysdep/mcontext.h> #include <linux/futex.h> -#include <linux/threads.h> #include <timetravel.h> -#include <asm-generic/rwonce.h> #include "../internal.h"

int is_skas_winch(int pid, int fd, void *data) @@ -204,7 +202,7 @@ void wait_stub_done_seccomp(struct mm_id *mm_idp, int running, int wait_sigsys) * Either way, if PID is negative, then we have no * choice but to kill the task. */ - if (__READ_ONCE(mm_idp->pid) < 0) + if (READ_ONCE(mm_idp->pid) < 0) goto out_kill;

ret = syscall(__NR_futex, &data->futex, @@ -217,7 +215,7 @@ void wait_stub_done_seccomp(struct mm_id *mm_idp, int running, int wait_sigsys) } } while (data->futex == FUTEX_IN_CHILD);

- if (__READ_ONCE(mm_idp->pid) < 0) + if (READ_ONCE(mm_idp->pid) < 0) goto out_kill;

running = 0; diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c index a827c2e01aa5..8971f4fdddab 100644 --- a/arch/um/os-Linux/start_up.c +++ b/arch/um/os-Linux/start_up.c @@ -28,8 +28,8 @@ #include <stdbool.h> #include <stub-data.h> #include <sys/prctl.h> -#include <linux/seccomp.h> -#include <linux/filter.h> +#include <uapi/linux/seccomp.h> +#include <uapi/linux/filter.h> #include <sysdep/mcontext.h> #include <sysdep/stub.h> #include <registers.h> diff --git a/arch/um/scripts/Makefile.rules b/arch/um/scripts/Makefile.rules index a8b7d9dab0a6..b4a2e0058503 100644 --- a/arch/um/scripts/Makefile.rules +++ b/arch/um/scripts/Makefile.rules @@ -9,7 +9,7 @@ USER_OBJS += $(filter %_user.o,$(obj-y) $(USER_SINGLE_OBJS)) USER_OBJS := $(foreach file,$(USER_OBJS),$(obj)/$(file))

$(USER_OBJS:.o=.%): \ - c_flags = -Wp,-MD,$(depfile) $(USER_CFLAGS) -include $(srctree)/include/linux/kern_levels.h -include user.h $(CFLAGS_$(basetarget).o) + c_flags = -Wp,-MD,$(depfile) $(USER_CFLAGS) $(CFLAGS_$(basetarget).o)

# These are like USER_OBJS but filter USER_CFLAGS through unprofile instead of # using it directly. diff --git a/arch/x86/um/Makefile b/arch/x86/um/Makefile index b42c31cd2390..e5f1658a8f9d 100644 --- a/arch/x86/um/Makefile +++ b/arch/x86/um/Makefile @@ -38,8 +38,10 @@ subarch-$(CONFIG_MODULES) += ../kernel/module.o

USER_OBJS := bugs_$(BITS).o ptrace_user.o fault.o

-$(obj)/user-offsets.s: c_flags = -Wp,-MD,$(depfile) $(USER_CFLAGS) \ - -Iarch/x86/include/generated +$(obj)/user-offsets.s: c_flags = -Wp,-MD,$(depfile) $(USER_CFLAGS) \ + -Iarch/x86/include/generated \ + -include include/linux/kbuild.h + targets += user-offsets.s

include/generated/user_constants.h: $(obj)/user-offsets.s FORCE diff --git a/arch/x86/um/user-offsets.c b/arch/x86/um/user-offsets.c index d6e1cd9956bf..74fc9763b76e 100644 --- a/arch/x86/um/user-offsets.c +++ b/arch/x86/um/user-offsets.c @@ -8,7 +8,6 @@ #define __FRAME_OFFSETS #include <linux/ptrace.h> #include <asm/types.h> -#include <linux/kbuild.h>

#define DEFINE_LONGS(sym, val) \ COMMENT(#val " / sizeof(unsigned long)"); \

From: Benjamin Berg benjamin.berg@intel.com

There is no errno variable when NOLIBC_IGNORE_ERRNO is defined. As such, the perror function does not make any sense then and cannot compile.

Fixes: acab7bcdb1bc ("tools/nolibc/stdio: add perror() to report the errno value") Signed-off-by: Benjamin Berg benjamin.berg@intel.com --- tools/include/nolibc/stdio.h | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h index 7630234408c5..c512159b8374 100644 --- a/tools/include/nolibc/stdio.h +++ b/tools/include/nolibc/stdio.h @@ -597,11 +597,13 @@ int sscanf(const char *str, const char *format, ...) return ret; }

+#ifndef NOLIBC_IGNORE_ERRNO static __attribute__((unused)) void perror(const char *msg) { fprintf(stderr, "%s%serrno=%d\n", (msg && *msg) ? msg : "", (msg && *msg) ? ": " : "", errno); } +#endif

static __attribute__((unused)) int setvbuf(FILE *stream __attribute__((unused)),

From: Benjamin Berg benjamin.berg@intel.com

Using errno is not possible when NOLIBC_IGNORE_ERRNO is set. Use sys_lseek instead of lseek as that avoids using errno.

Fixes: 665fa8dea90d ("tools/nolibc: add support for directory access") Signed-off-by: Benjamin Berg benjamin.berg@intel.com --- tools/include/nolibc/dirent.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/include/nolibc/dirent.h b/tools/include/nolibc/dirent.h index 758b95c48e7a..61a122a60327 100644 --- a/tools/include/nolibc/dirent.h +++ b/tools/include/nolibc/dirent.h @@ -86,9 +86,9 @@ int readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result) * readdir() can only return one entry at a time. * Make sure the non-returned ones are not skipped. */ - ret = lseek(fd, ldir->d_off, SEEK_SET); - if (ret == -1) - return errno; + ret = sys_lseek(fd, ldir->d_off, SEEK_SET); + if (ret < 0) + return -ret;

entry->d_ino = ldir->d_ino; /* the destination should always be big enough */

From: Benjamin Berg benjamin.berg@intel.com

Use the version of the attribute with underscores to avoid issues if fallthrough has been defined by another header file already.

Signed-off-by: Benjamin Berg benjamin.berg@intel.com --- tools/include/nolibc/compiler.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/include/nolibc/compiler.h b/tools/include/nolibc/compiler.h index 369cfb5a0e78..87090bbc53e0 100644 --- a/tools/include/nolibc/compiler.h +++ b/tools/include/nolibc/compiler.h @@ -41,8 +41,8 @@ # define __no_stack_protector __attribute__((__optimize__("-fno-stack-protector"))) #endif /* __nolibc_has_attribute(no_stack_protector) */

-#if __nolibc_has_attribute(fallthrough) -# define __nolibc_fallthrough do { } while (0); __attribute__((fallthrough)) +#if __nolibc_has_attribute(__fallthrough__) +# define __nolibc_fallthrough do { } while (0); __attribute__((__fallthrough__)) #else # define __nolibc_fallthrough do { } while (0) #endif /* __nolibc_has_attribute(fallthrough) */

From: Benjamin Berg benjamin.berg@intel.com

In principle, it is possible to use nolibc for only some object files in a program. In that case, the startup code in _start and _start_c is not going to be used. Add the NOLIBC_NO_STARTCODE compile time option to disable it entirely and also remove anything that depends on it.

Doing this avoids warnings from modpost for UML as the _start_c code references the main function from the .init.text section while it is not inside .init itself.

Signed-off-by: Benjamin Berg benjamin.berg@intel.com --- tools/include/nolibc/arch-arm.h | 2 ++ tools/include/nolibc/arch-arm64.h | 2 ++ tools/include/nolibc/arch-loongarch.h | 2 ++ tools/include/nolibc/arch-m68k.h | 2 ++ tools/include/nolibc/arch-mips.h | 2 ++ tools/include/nolibc/arch-powerpc.h | 2 ++ tools/include/nolibc/arch-riscv.h | 2 ++ tools/include/nolibc/arch-s390.h | 2 ++ tools/include/nolibc/arch-sh.h | 2 ++ tools/include/nolibc/arch-sparc.h | 2 ++ tools/include/nolibc/arch-x86.h | 4 ++++ tools/include/nolibc/crt.h | 3 +++ tools/include/nolibc/stackprotector.h | 2 ++ tools/include/nolibc/stdlib.h | 2 ++ tools/include/nolibc/sys.h | 3 ++- tools/include/nolibc/sys/auxv.h | 3 +++ 16 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/tools/include/nolibc/arch-arm.h b/tools/include/nolibc/arch-arm.h index 1f66e7e5a444..24ad348cc1e8 100644 --- a/tools/include/nolibc/arch-arm.h +++ b/tools/include/nolibc/arch-arm.h @@ -185,6 +185,7 @@ })

/* startup code */ +#ifndef NOLIBC_NO_STARTCODE void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void) { __asm__ volatile ( @@ -193,5 +194,6 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _s ); __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */

#endif /* _NOLIBC_ARCH_ARM_H */ diff --git a/tools/include/nolibc/arch-arm64.h b/tools/include/nolibc/arch-arm64.h index 02a3f74c8ec8..554ebb51c761 100644 --- a/tools/include/nolibc/arch-arm64.h +++ b/tools/include/nolibc/arch-arm64.h @@ -142,6 +142,7 @@ })

/* startup code */ +#ifndef NOLIBC_NO_STARTCODE void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void) { __asm__ volatile ( @@ -150,4 +151,5 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _s ); __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */ #endif /* _NOLIBC_ARCH_ARM64_H */ diff --git a/tools/include/nolibc/arch-loongarch.h b/tools/include/nolibc/arch-loongarch.h index 5511705303ea..cf14f7bf4081 100644 --- a/tools/include/nolibc/arch-loongarch.h +++ b/tools/include/nolibc/arch-loongarch.h @@ -143,6 +143,7 @@ })

/* startup code */ +#ifndef NOLIBC_NO_STARTCODE void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void) { __asm__ volatile ( @@ -151,5 +152,6 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _s ); __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */

#endif /* _NOLIBC_ARCH_LOONGARCH_H */ diff --git a/tools/include/nolibc/arch-m68k.h b/tools/include/nolibc/arch-m68k.h index 6dac1845f298..dc0d48a10c14 100644 --- a/tools/include/nolibc/arch-m68k.h +++ b/tools/include/nolibc/arch-m68k.h @@ -128,6 +128,7 @@ _num; \ })

+#ifndef NOLIBC_NO_STARTCODE void _start(void); void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void) { @@ -137,5 +138,6 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _s ); __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */

#endif /* _NOLIBC_ARCH_M68K_H */ diff --git a/tools/include/nolibc/arch-mips.h b/tools/include/nolibc/arch-mips.h index 0cbac63b249a..6c6a65a99029 100644 --- a/tools/include/nolibc/arch-mips.h +++ b/tools/include/nolibc/arch-mips.h @@ -246,6 +246,7 @@ #endif /* _ABIO32 */

/* startup code, note that it's called __start on MIPS */ +#ifndef NOLIBC_NO_STARTCODE void __start(void); void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector __start(void) { @@ -266,5 +267,6 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector __ ); __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */

#endif /* _NOLIBC_ARCH_MIPS_H */ diff --git a/tools/include/nolibc/arch-powerpc.h b/tools/include/nolibc/arch-powerpc.h index 204564bbcd32..7a01278e569c 100644 --- a/tools/include/nolibc/arch-powerpc.h +++ b/tools/include/nolibc/arch-powerpc.h @@ -184,6 +184,7 @@ #endif /* !__powerpc64__ */

/* startup code */ +#ifndef NOLIBC_NO_STARTCODE void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void) { #ifdef __powerpc64__ @@ -215,5 +216,6 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _s #endif __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */

#endif /* _NOLIBC_ARCH_POWERPC_H */ diff --git a/tools/include/nolibc/arch-riscv.h b/tools/include/nolibc/arch-riscv.h index 885383a86c38..12ca37b8d964 100644 --- a/tools/include/nolibc/arch-riscv.h +++ b/tools/include/nolibc/arch-riscv.h @@ -140,6 +140,7 @@ })

/* startup code */ +#ifndef NOLIBC_NO_STARTCODE void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void) { __asm__ volatile ( @@ -152,5 +153,6 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _s ); __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */

#endif /* _NOLIBC_ARCH_RISCV_H */ diff --git a/tools/include/nolibc/arch-s390.h b/tools/include/nolibc/arch-s390.h index df4c3cc713ac..fb0d312847b8 100644 --- a/tools/include/nolibc/arch-s390.h +++ b/tools/include/nolibc/arch-s390.h @@ -140,6 +140,7 @@ })

/* startup code */ +#ifndef NOLIBC_NO_STARTCODE void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void) { __asm__ volatile ( @@ -155,6 +156,7 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _s ); __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */

struct s390_mmap_arg_struct { unsigned long addr; diff --git a/tools/include/nolibc/arch-sh.h b/tools/include/nolibc/arch-sh.h index a96b8914607e..038bf364aa27 100644 --- a/tools/include/nolibc/arch-sh.h +++ b/tools/include/nolibc/arch-sh.h @@ -141,6 +141,7 @@ })

/* startup code */ +#ifndef NOLIBC_NO_STARTCODE void _start_wrapper(void); void __attribute__((weak,noreturn)) __nolibc_entrypoint __no_stack_protector _start_wrapper(void) { @@ -158,5 +159,6 @@ void __attribute__((weak,noreturn)) __nolibc_entrypoint __no_stack_protector _st ); __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */

#endif /* _NOLIBC_ARCH_SH_H */ diff --git a/tools/include/nolibc/arch-sparc.h b/tools/include/nolibc/arch-sparc.h index ca420d843e25..062eae1fa92d 100644 --- a/tools/include/nolibc/arch-sparc.h +++ b/tools/include/nolibc/arch-sparc.h @@ -153,6 +153,7 @@ })

/* startup code */ +#ifndef NOLIBC_NO_STARTCODE void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void) { __asm__ volatile ( @@ -169,6 +170,7 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _s ); __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */

static pid_t getpid(void);

diff --git a/tools/include/nolibc/arch-x86.h b/tools/include/nolibc/arch-x86.h index d3efc0c3b8ad..b4981e99f0a0 100644 --- a/tools/include/nolibc/arch-x86.h +++ b/tools/include/nolibc/arch-x86.h @@ -164,6 +164,7 @@ * 2) The deepest stack frame should be set to zero * */ +#ifndef NOLIBC_NO_STARTCODE void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void) { __asm__ volatile ( @@ -176,6 +177,7 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _s ); __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */

#else /* !defined(__x86_64__) */

@@ -330,6 +332,7 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _s * 2) The deepest stack frame should be zero (the %rbp). * */ +#ifndef NOLIBC_NO_STARTCODE void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void) { __asm__ volatile ( @@ -340,6 +343,7 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _s ); __nolibc_entrypoint_epilogue(); } +#endif /* NOLIBC_NO_STARTCODE */

#define NOLIBC_ARCH_HAS_MEMMOVE void *memmove(void *dst, const void *src, size_t len); diff --git a/tools/include/nolibc/crt.h b/tools/include/nolibc/crt.h index 961cfe777c35..d72e616eeec9 100644 --- a/tools/include/nolibc/crt.h +++ b/tools/include/nolibc/crt.h @@ -7,6 +7,8 @@ #ifndef _NOLIBC_CRT_H #define _NOLIBC_CRT_H

+#ifndef NOLIBC_NO_STARTCODE + #include "compiler.h"

char **environ __attribute__((weak)); @@ -88,4 +90,5 @@ void _start_c(long *sp) exit(exitcode); }

+#endif /* NOLIBC_NO_STARTCODE */ #endif /* _NOLIBC_CRT_H */ diff --git a/tools/include/nolibc/stackprotector.h b/tools/include/nolibc/stackprotector.h index c71a2c257177..3dd4d3e53ca6 100644 --- a/tools/include/nolibc/stackprotector.h +++ b/tools/include/nolibc/stackprotector.h @@ -9,6 +9,7 @@

#include "compiler.h"

+#ifndef NOLIBC_NO_STARTCODE #if defined(_NOLIBC_STACKPROTECTOR)

#include "sys.h" @@ -49,5 +50,6 @@ static __no_stack_protector void __stack_chk_init(void) #else /* !defined(_NOLIBC_STACKPROTECTOR) */ static void __stack_chk_init(void) {} #endif /* defined(_NOLIBC_STACKPROTECTOR) */ +#endif /* NOLIBC_NO_STARTCODE */

#endif /* _NOLIBC_STACKPROTECTOR_H */ diff --git a/tools/include/nolibc/stdlib.h b/tools/include/nolibc/stdlib.h index 5fd99a480f82..ed12c9119aab 100644 --- a/tools/include/nolibc/stdlib.h +++ b/tools/include/nolibc/stdlib.h @@ -107,6 +107,7 @@ void free(void *ptr) * environment variable exists its value is returned otherwise NULL is * returned. */ +#ifndef NOLIBC_NO_STARTCODE static __attribute__((unused)) char *getenv(const char *name) { @@ -122,6 +123,7 @@ char *getenv(const char *name) } return NULL; } +#endif /* NOLIBC_NO_STARTCODE */

static __attribute__((unused)) void *malloc(size_t len) diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h index 295e71d34aba..c518a1b4af97 100644 --- a/tools/include/nolibc/sys.h +++ b/tools/include/nolibc/sys.h @@ -509,6 +509,7 @@ pid_t gettid(void) return sys_gettid(); }

+#ifndef NOLIBC_NO_STARTCODE static unsigned long getauxval(unsigned long key);

/* @@ -520,7 +521,7 @@ int getpagesize(void) { return __sysret((int)getauxval(AT_PAGESZ) ?: -ENOENT); } - +#endif /* NOLIBC_NO_STARTCODE */

/* * uid_t getuid(void); diff --git a/tools/include/nolibc/sys/auxv.h b/tools/include/nolibc/sys/auxv.h index c52463d6c18d..35d339146463 100644 --- a/tools/include/nolibc/sys/auxv.h +++ b/tools/include/nolibc/sys/auxv.h @@ -10,6 +10,8 @@ #ifndef _NOLIBC_SYS_AUXV_H #define _NOLIBC_SYS_AUXV_H

+#ifndef NOLIBC_NO_STARTCODE + #include "../crt.h"

static __attribute__((unused)) @@ -38,4 +40,5 @@ unsigned long getauxval(unsigned long type) return ret; }

+#endif /* NOLIBC_NO_STARTCODE */ #endif /* _NOLIBC_SYS_AUXV_H */

From: Benjamin Berg benjamin.berg@intel.com

Add NOLIBC_CFLAGS and NOLIBC_OBJS to build files against nolibc rather than libc. With this it is possible to move to nolibc in smaller steps.

Set NOLIBC_IGNORE_ERRNO, as the nolibc errno implementation is overly simple and cannot handle threading. nolibc provides sys_* functions that do not emulate the libc errno behaviour and can be used instead.

Guard the syscall definition as it is a macro in nolibc.

Signed-off-by: Benjamin Berg benjamin.berg@intel.com --- arch/um/Makefile | 21 ++++++++++++++++++++- arch/um/include/shared/os.h | 2 ++ arch/um/scripts/Makefile.rules | 8 +++++++- 3 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/arch/um/Makefile b/arch/um/Makefile index a3f27d791cc0..54aa26fcc32b 100644 --- a/arch/um/Makefile +++ b/arch/um/Makefile @@ -78,6 +78,25 @@ USER_CFLAGS = $(patsubst $(KERNEL_DEFINES),,$(patsubst -I%,,$(KBUILD_CFLAGS))) \ -include $(srctree)/include/linux/kern_levels.h \ -include $(srctree)/$(ARCH_DIR)/include/shared/user.h

+NOLIBC_CFLAGS = $(patsubst $(KERNEL_DEFINES),,$(patsubst -I%,,$(KBUILD_CFLAGS))) \ + $(ARCH_INCLUDE) $(MODE_INCLUDE) $(filter -I%,$(CFLAGS)) \ + -I $(srctree)/tools/include \ + -D__EXPORTED_HEADERS__ \ + -D__UM_HOST__ -D__UM_NOLIBC__ \ + -DNOLIBC_NO_STARTCODE \ + -DNOLIBC_IGNORE_ERRNO \ + -nostdlib -nostdinc -static \ + -I$(srctree)/include/uapi \ + -I$(srctree)/$(HOST_DIR)/include/uapi \ + -I$(objtree)/$(HOST_DIR)/include/generated/uapi \ + -I $(srctree)/tools/include/nolibc \ + -I $(srctree)/usr/include \ + -include $(srctree)/include/generated/autoconf.h \ + -include $(srctree)/tools/include/linux/kconfig.h \ + -include $(srctree)/include/linux/kern_levels.h \ + -include $(srctree)/tools/include/nolibc/nolibc.h \ + -include $(srctree)/$(ARCH_DIR)/include/shared/user.h + #This will adjust *FLAGS accordingly to the platform. include $(srctree)/$(ARCH_DIR)/Makefile-os-Linux

@@ -157,4 +176,4 @@ archclean: -o -name '*.gcov' ) -type f -print | xargs rm -f $(Q)$(MAKE) -f $(srctree)/Makefile ARCH=$(HEADER_ARCH) clean

-export HEADER_ARCH SUBARCH USER_CFLAGS CFLAGS_NO_HARDENING DEV_NULL_PATH +export HEADER_ARCH SUBARCH USER_CFLAGS NOLIBC_CFLAGS CFLAGS_NO_HARDENING DEV_NULL_PATH diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h index b35cc8ce333b..3e9f3ae61658 100644 --- a/arch/um/include/shared/os.h +++ b/arch/um/include/shared/os.h @@ -327,7 +327,9 @@ extern int __ignore_sigio_fd(int fd); /* tty.c */ extern int get_pty(void);

+#ifndef syscall long syscall(long number, ...); +#endif

/* irqflags tracing */ extern void block_signals_trace(void); diff --git a/arch/um/scripts/Makefile.rules b/arch/um/scripts/Makefile.rules index b4a2e0058503..5f07551935c3 100644 --- a/arch/um/scripts/Makefile.rules +++ b/arch/um/scripts/Makefile.rules @@ -11,6 +11,12 @@ USER_OBJS := $(foreach file,$(USER_OBJS),$(obj)/$(file)) $(USER_OBJS:.o=.%): \ c_flags = -Wp,-MD,$(depfile) $(USER_CFLAGS) $(CFLAGS_$(basetarget).o)

+# Similar USER_OBJS but compiled against nolibc (may include kernel headers?) +NOLIBC_OBJS := $(foreach file,$(NOLIBC_OBJS),$(obj)/$(file)) + +$(NOLIBC_OBJS:.o=.%): \ + c_flags = -Wp,-MD,$(depfile) $(NOLIBC_CFLAGS) $(CFLAGS_$(basetarget).o) + # These are like USER_OBJS but filter USER_CFLAGS through unprofile instead of # using it directly. UNPROFILE_OBJS := $(foreach file,$(UNPROFILE_OBJS),$(obj)/$(file)) @@ -18,7 +24,7 @@ UNPROFILE_OBJS := $(foreach file,$(UNPROFILE_OBJS),$(obj)/$(file)) $(UNPROFILE_OBJS:.o=.%): \ c_flags = -Wp,-MD,$(depfile) $(call unprofile,$(USER_CFLAGS)) $(CFLAGS_$(basetarget).o)

-$(USER_OBJS) $(UNPROFILE_OBJS): \ +$(USER_OBJS) $(NOLIBC_OBJS) $(UNPROFILE_OBJS): \ CHECKFLAGS := $(patsubst $(NOSTDINC_FLAGS),,$(CHECKFLAGS))

# The stubs can't try to call mcount or update basic block data

From: Benjamin Berg benjamin.berg@intel.com

This is one of the simplest files and it can be switched over to use nolibc without any modifications.

Signed-off-by: Benjamin Berg benjamin.berg@intel.com --- arch/um/kernel/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/um/kernel/Makefile b/arch/um/kernel/Makefile index b8f4e9281599..4b206a40b611 100644 --- a/arch/um/kernel/Makefile +++ b/arch/um/kernel/Makefile @@ -26,7 +26,7 @@ obj-$(CONFIG_OF) += dtb.o obj-$(CONFIG_EARLY_PRINTK) += early_printk.o obj-$(CONFIG_STACKTRACE) += stacktrace.o

-USER_OBJS := config.o +NOLIBC_OBJS := config.o

include $(srctree)/arch/um/scripts/Makefile.rules