projects/linux·commit 418becac

Merge tag 'nolibc-20250308-for-6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

418becac · Linus Torvalds <[email protected]> · 2025-03-24 17:59:29 -07:00

Pull nolibc updates from Paul McKenney:
 - 32bit s390 support
 - opendir() and friends
 - openat() support
 - sscanf() support
 - various cleanups

[ Paul has just forwarded the pull request from Thomas Weißschuh, so
  the tag signature is from Thomas, not Paul   - Linus ]

* tag 'nolibc-20250308-for-6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (26 commits)
  tools/nolibc: don't use asm/ UAPI headers
  selftests/nolibc: stop testing constructor order
  selftests/nolibc: use O_RDONLY flag instead of 0
  tools/nolibc: drop outdated example from overview comment
  tools/nolibc: process open() vararg as mode_t
  tools/nolibc: always use openat(2) instead of open(2)
  tools/nolibc: add support for openat(2)
  selftests/nolibc: add armthumb configuration
  selftests/nolibc: explicitly enable ARM mode
  Revert "selftests: kselftest: Fix build failure with NOLIBC"
  tools/nolibc: add support for [v]sscanf()
  tools/nolibc: add support for 32-bit s390
  selftests/nolibc: rename s390 to s390x
  selftests/nolibc: only run constructor tests on nolibc
  selftests/nolibc: split up architecture list in run-tests.sh
  tools/nolibc: add support for directory access
  tools/nolibc: add support for sys_llseek()
  selftests/nolibc: always keep test kernel configuration up to date
  selftests/nolibc: execute defconfig before other targets
  selftests/nolibc: drop call to mrproper target
  ...
Commit
418becac37efeae6e3e422abff09e79addaef66b
Parents
bcb04425 · bceb7390

Merge commit. Changes below are compared with the first parent: bcb04425.

Changes

19 files changed · +457 −56

Only the first 600 diff lines are shown. Download the complete patch.

tools/include/nolibc/Makefile

View file
diff --git a/tools/include/nolibc/Makefile b/tools/include/nolibc/Makefile
index a1f55fb..dceec0e 100644
--- a/tools/include/nolibc/Makefile
+++ b/tools/include/nolibc/Makefile
@@ -29,6 +29,7 @@ all_files := \
compiler.h \
crt.h \
ctype.h \
+ dirent.h \
errno.h \
nolibc.h \
signal.h \

tools/include/nolibc/arch-mips.h

View file
diff --git a/tools/include/nolibc/arch-mips.h b/tools/include/nolibc/arch-mips.h
index 1791a8c..753a8ed 100644
--- a/tools/include/nolibc/arch-mips.h
+++ b/tools/include/nolibc/arch-mips.h
@@ -179,6 +179,7 @@
})
/* startup code, note that it's called __start on MIPS */
+void __start(void);
void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector __start(void)
{
__asm__ volatile (

tools/include/nolibc/arch-s390.h

View file
diff --git a/tools/include/nolibc/arch-s390.h b/tools/include/nolibc/arch-s390.h
index f9ab83a..df4c3cc 100644
--- a/tools/include/nolibc/arch-s390.h
+++ b/tools/include/nolibc/arch-s390.h
@@ -5,8 +5,8 @@
#ifndef _NOLIBC_ARCH_S390_H
#define _NOLIBC_ARCH_S390_H
-#include <asm/signal.h>
-#include <asm/unistd.h>
+#include <linux/signal.h>
+#include <linux/unistd.h>
#include "compiler.h"
#include "crt.h"
@@ -143,8 +143,13 @@
void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
{
__asm__ volatile (
+#ifdef __s390x__
"lgr %r2, %r15\n" /* save stack pointer to %r2, as arg1 of _start_c */
"aghi %r15, -160\n" /* allocate new stackframe */
+#else
+ "lr %r2, %r15\n"
+ "ahi %r15, -96\n"
+#endif
"xc 0(8,%r15), 0(%r15)\n" /* clear backchain */
"brasl %r14, _start_c\n" /* transfer to c runtime */
);

tools/include/nolibc/arch.h

View file
diff --git a/tools/include/nolibc/arch.h b/tools/include/nolibc/arch.h
index c8f4e5d..8a2c143 100644
--- a/tools/include/nolibc/arch.h
+++ b/tools/include/nolibc/arch.h
@@ -29,7 +29,7 @@
#include "arch-powerpc.h"
#elif defined(__riscv)
#include "arch-riscv.h"
-#elif defined(__s390x__)
+#elif defined(__s390x__) || defined(__s390__)
#include "arch-s390.h"
#elif defined(__loongarch__)
#include "arch-loongarch.h"

tools/include/nolibc/crt.h

View file
diff --git a/tools/include/nolibc/crt.h b/tools/include/nolibc/crt.h
index bbcd5fd..c4b1010 100644
--- a/tools/include/nolibc/crt.h
+++ b/tools/include/nolibc/crt.h
@@ -10,6 +10,7 @@
char **environ __attribute__((weak));
const unsigned long *_auxv __attribute__((weak));
+void _start(void);
static void __stack_chk_init(void);
static void exit(int);
@@ -22,6 +23,7 @@ extern void (*const __init_array_end[])(int, char **, char**) __attribute__((wea
extern void (*const __fini_array_start[])(void) __attribute__((weak));
extern void (*const __fini_array_end[])(void) __attribute__((weak));
+void _start_c(long *sp);
__attribute__((weak,used))
void _start_c(long *sp)
{

tools/include/nolibc/dirent.h

View file
diff --git a/tools/include/nolibc/dirent.h b/tools/include/nolibc/dirent.h
new file mode 100644
index 0000000..c5c30d0
--- /dev/null
+++ b/tools/include/nolibc/dirent.h
@@ -0,0 +1,98 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * Directory access for NOLIBC
+ * Copyright (C) 2025 Thomas Weißschuh <[email protected]>
+ */
+
+#ifndef _NOLIBC_DIRENT_H
+#define _NOLIBC_DIRENT_H
+
+#include "stdint.h"
+#include "types.h"
+
+#include <linux/limits.h>
+
+struct dirent {
+ ino_t d_ino;
+ char d_name[NAME_MAX + 1];
+};
+
+/* See comment of FILE in stdio.h */
+typedef struct {
+ char dummy[1];
+} DIR;
+
+static __attribute__((unused))
+DIR *fdopendir(int fd)
+{
+ if (fd < 0) {
+ SET_ERRNO(EBADF);
+ return NULL;
+ }
+ return (DIR *)(intptr_t)~fd;
+}
+
+static __attribute__((unused))
+DIR *opendir(const char *name)
+{
+ int fd;
+
+ fd = open(name, O_RDONLY);
+ if (fd == -1)
+ return NULL;
+ return fdopendir(fd);
+}
+
+static __attribute__((unused))
+int closedir(DIR *dirp)
+{
+ intptr_t i = (intptr_t)dirp;
+
+ if (i >= 0) {
+ SET_ERRNO(EBADF);
+ return -1;
+ }
+ return close(~i);
+}
+
+static __attribute__((unused))
+int readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result)
+{
+ char buf[sizeof(struct linux_dirent64) + NAME_MAX + 1];
+ struct linux_dirent64 *ldir = (void *)buf;
+ intptr_t i = (intptr_t)dirp;
+ int fd, ret;
+
+ if (i >= 0)
+ return EBADF;
+
+ fd = ~i;
+
+ ret = sys_getdents64(fd, ldir, sizeof(buf));
+ if (ret < 0)
+ return -ret;
+ if (ret == 0) {
+ *result = NULL;
+ return 0;
+ }
+
+ /*
+ * getdents64() returns as many entries as fit the buffer.
+ * 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;
+
+ entry->d_ino = ldir->d_ino;
+ /* the destination should always be big enough */
+ strlcpy(entry->d_name, ldir->d_name, sizeof(entry->d_name));
+ *result = entry;
+ return 0;
+}
+
+/* make sure to include all global symbols */
+#include "nolibc.h"
+
+#endif /* _NOLIBC_DIRENT_H */

tools/include/nolibc/errno.h

View file
diff --git a/tools/include/nolibc/errno.h b/tools/include/nolibc/errno.h
index a44486f..1d8d803 100644
--- a/tools/include/nolibc/errno.h
+++ b/tools/include/nolibc/errno.h
@@ -7,7 +7,7 @@
#ifndef _NOLIBC_ERRNO_H
#define _NOLIBC_ERRNO_H
-#include <asm/errno.h>
+#include <linux/errno.h>
#ifndef NOLIBC_IGNORE_ERRNO
#define SET_ERRNO(v) do { errno = (v); } while (0)

tools/include/nolibc/nolibc.h

View file
diff --git a/tools/include/nolibc/nolibc.h b/tools/include/nolibc/nolibc.h
index 92436b1..7087240 100644
--- a/tools/include/nolibc/nolibc.h
+++ b/tools/include/nolibc/nolibc.h
@@ -31,8 +31,7 @@
* - The third level is the libc call definition. It exposes the lower raw
* sys_<name>() calls in a way that looks like what a libc usually does,
* takes care of specific input values, and of setting errno upon error.
- * There can be minor variations compared to standard libc calls. For
- * example the open() call always takes 3 args here.
+ * There can be minor variations compared to standard libc calls.
*
* The errno variable is declared static and unused. This way it can be
* optimized away if not used. However this means that a program made of
@@ -105,6 +104,7 @@
#include "string.h"
#include "time.h"
#include "stackprotector.h"
+#include "dirent.h"
/* Used by programs to avoid std includes */
#define NOLIBC

tools/include/nolibc/signal.h

View file
diff --git a/tools/include/nolibc/signal.h b/tools/include/nolibc/signal.h
index 1375522..cdcc590 100644
--- a/tools/include/nolibc/signal.h
+++ b/tools/include/nolibc/signal.h
@@ -13,6 +13,7 @@
#include "sys.h"
/* This one is not marked static as it's needed by libgcc for divide by zero */
+int raise(int signal);
__attribute__((weak,unused,section(".text.nolibc_raise")))
int raise(int signal)
{

tools/include/nolibc/stackprotector.h

View file
diff --git a/tools/include/nolibc/stackprotector.h b/tools/include/nolibc/stackprotector.h
index 1d0d525..c71a2c2 100644
--- a/tools/include/nolibc/stackprotector.h
+++ b/tools/include/nolibc/stackprotector.h
@@ -18,6 +18,7 @@
* triggering stack protector errors themselves
*/
+void __stack_chk_fail(void);
__attribute__((weak,used,noreturn,section(".text.nolibc_stack_chk")))
void __stack_chk_fail(void)
{
@@ -28,6 +29,7 @@ void __stack_chk_fail(void)
for (;;);
}
+void __stack_chk_fail_local(void);
__attribute__((weak,noreturn,section(".text.nolibc_stack_chk")))
void __stack_chk_fail_local(void)
{

tools/include/nolibc/stdio.h

View file
diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h
index 3892034..a403351 100644
--- a/tools/include/nolibc/stdio.h
+++ b/tools/include/nolibc/stdio.h
@@ -350,6 +350,104 @@ int printf(const char *fmt, ...)
}
static __attribute__((unused))
+int vsscanf(const char *str, const char *format, va_list args)
+{
+ uintmax_t uval;
+ intmax_t ival;
+ int base;
+ char *endptr;
+ int matches;
+ int lpref;
+
+ matches = 0;
+
+ while (1) {
+ if (*format == '%') {
+ /* start of pattern */
+ lpref = 0;
+ format++;
+
+ if (*format == 'l') {
+ /* same as in printf() */
+ lpref = 1;
+ format++;
+ if (*format == 'l') {
+ lpref = 2;
+ format++;
+ }
+ }
+
+ if (*format == '%') {
+ /* literal % */
+ if ('%' != *str)
+ goto done;
+ str++;
+ format++;
+ continue;
+ } else if (*format == 'd') {
+ ival = strtoll(str, &endptr, 10);
+ if (lpref == 0)
+ *va_arg(args, int *) = ival;
+ else if (lpref == 1)
+ *va_arg(args, long *) = ival;
+ else if (lpref == 2)
+ *va_arg(args, long long *) = ival;
+ } else if (*format == 'u' || *format == 'x' || *format == 'X') {
+ base = *format == 'u' ? 10 : 16;
+ uval = strtoull(str, &endptr, base);
+ if (lpref == 0)
+ *va_arg(args, unsigned int *) = uval;
+ else if (lpref == 1)
+ *va_arg(args, unsigned long *) = uval;
+ else if (lpref == 2)
+ *va_arg(args, unsigned long long *) = uval;
+ } else if (*format == 'p') {
+ *va_arg(args, void **) = (void *)strtoul(str, &endptr, 16);
+ } else {
+ SET_ERRNO(EILSEQ);
+ goto done;
+ }
+
+ format++;
+ str = endptr;
+ matches++;
+
+ } else if (*format == '\0') {
+ goto done;
+ } else if (isspace(*format)) {
+ /* skip spaces in format and str */
+ while (isspace(*format))
+ format++;
+ while (isspace(*str))
+ str++;
+ } else if (*format == *str) {
+ /* literal match */
+ format++;
+ str++;
+ } else {
+ if (!matches)
+ matches = EOF;
+ goto done;
+ }
+ }
+
+done:
+ return matches;
+}
+
+static __attribute__((unused, format(scanf, 2, 3)))
+int sscanf(const char *str, const char *format, ...)
+{
+ va_list args;
+ int ret;
+
+ va_start(args, format);
+ ret = vsscanf(str, format, args);
+ va_end(args);
+ return ret;
+}
+
+static __attribute__((unused))
void perror(const char *msg)
{
fprintf(stderr, "%s%serrno=%d\n", (msg && *msg) ? msg : "", (msg && *msg) ? ": " : "", errno);

tools/include/nolibc/stdlib.h

View file
diff --git a/tools/include/nolibc/stdlib.h b/tools/include/nolibc/stdlib.h
index 75aa273..86ad378 100644
--- a/tools/include/nolibc/stdlib.h
+++ b/tools/include/nolibc/stdlib.h
@@ -30,6 +30,7 @@ static __attribute__((unused)) char itoa_buffer[21];
*/
/* must be exported, as it's used by libgcc for various divide functions */
+void abort(void);
__attribute__((weak,unused,noreturn,section(".text.nolibc_abort")))
void abort(void)
{

tools/include/nolibc/string.h

View file
diff --git a/tools/include/nolibc/string.h b/tools/include/nolibc/string.h
index 9ec9c24..ba84ab7 100644
--- a/tools/include/nolibc/string.h
+++ b/tools/include/nolibc/string.h
@@ -32,6 +32,7 @@ int memcmp(const void *s1, const void *s2, size_t n)
/* might be ignored by the compiler without -ffreestanding, then found as
* missing.
*/
+void *memmove(void *dst, const void *src, size_t len);
__attribute__((weak,unused,section(".text.nolibc_memmove")))
void *memmove(void *dst, const void *src, size_t len)
{
@@ -56,6 +57,7 @@ void *memmove(void *dst, const void *src, size_t len)
#ifndef NOLIBC_ARCH_HAS_MEMCPY
/* must be exported, as it's used by libgcc on ARM */
+void *memcpy(void *dst, const void *src, size_t len);
__attribute__((weak,unused,section(".text.nolibc_memcpy")))
void *memcpy(void *dst, const void *src, size_t len)
{
@@ -73,6 +75,7 @@ void *memcpy(void *dst, const void *src, size_t len)
/* might be ignored by the compiler without -ffreestanding, then found as
* missing.
*/
+void *memset(void *dst, int b, size_t len);
__attribute__((weak,unused,section(".text.nolibc_memset")))
void *memset(void *dst, int b, size_t len)
{
@@ -124,6 +127,7 @@ char *strcpy(char *dst, const char *src)
* thus itself, hence the asm() statement below that's meant to disable this
* confusing practice.
*/
+size_t strlen(const char *str);
__attribute__((weak,unused,section(".text.nolibc_strlen")))
size_t strlen(const char *str)
{

tools/include/nolibc/sys.h

View file
diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h
index d4a5c23..08c1c07 100644
--- a/tools/include/nolibc/sys.h
+++ b/tools/include/nolibc/sys.h
@@ -10,10 +10,10 @@
#include "std.h"
/* system includes */
-#include <asm/unistd.h>
-#include <asm/signal.h> /* for SIGCHLD */
-#include <asm/ioctls.h>
-#include <asm/mman.h>
+#include <linux/unistd.h>
+#include <linux/signal.h> /* for SIGCHLD */
+#include <linux/termios.h>
+#include <linux/mman.h>
#include <linux/fs.h>
#include <linux/loop.h>
#include <linux/time.h>
@@ -23,7 +23,6 @@
#include <linux/prctl.h>
#include <linux/resource.h>
#include <linux/utsname.h>
-#include <linux/signal.h>
#include "arch.h"
#include "errno.h"
@@ -532,20 +531,16 @@ uid_t getuid(void)
/*
- * int ioctl(int fd, unsigned long req, void *value);
+ * int ioctl(int fd, unsigned long cmd, ... arg);
*/
static __attribute__((unused))
-int sys_ioctl(int fd, unsigned long req, void *value)
+long sys_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
{
- return my_syscall3(__NR_ioctl, fd, req, value);
+ return my_syscall3(__NR_ioctl, fd, cmd, arg);
}
-static __attribute__((unused))
-int ioctl(int fd, unsigned long req, void *value)
-{
- return __sysret(sys_ioctl(fd, req, value));
-}
+#define ioctl(fd, cmd, arg) __sysret(sys_ioctl(fd, cmd, (unsigned long)(arg)))
/*
* int kill(pid_t pid, int signal);
@@ -602,9 +597,36 @@ off_t sys_lseek(int fd, off_t offset, int whence)
}
static __attribute__((unused))
+int sys_llseek(int fd, unsigned long offset_high, unsigned long offset_low,
+ __kernel_loff_t *result, int whence)
+{
+#ifdef __NR_llseek
+ return my_syscall5(__NR_llseek, fd, offset_high, offset_low, result, whence);
+#else
+ return __nolibc_enosys(__func__, fd, offset_high, offset_low, result, whence);
+#endif
+}
+
+static __attribute__((unused))
off_t lseek(int fd, off_t offset, int whence)
{
- return __sysret(sys_lseek(fd, offset, whence));
+ __kernel_loff_t loff = 0;
+ off_t result;
+ int ret;
+
+ result = sys_lseek(fd, offset, whence);
+ if (result == -ENOSYS) {
+ /* Only exists on 32bit where nolibc off_t is also 32bit */
+ ret = sys_llseek(fd, 0, offset, &loff, whence);
+ if (ret < 0)
+ result = ret;
+ else if (loff != (off_t)loff)
+ result = -EOVERFLOW;
+ else
+ result = loff;
+ }
+
+ return __sysret(result);
}
@@ -742,6 +764,31 @@ int mount(const char *src, const char *tgt,
return __sysret(sys_mount(src, tgt, fst, flags, data));
}
+/*
+ * int openat(int dirfd, const char *path, int flags[, mode_t mode]);
+ */
+
+static __attribute__((unused))
+int sys_openat(int dirfd, const char *path, int flags, mode_t mode)
+{
+ return my_syscall4(__NR_openat, dirfd, path, flags, mode);
+}
+
+static __attribute__((unused))
+int openat(int dirfd, const char *path, int flags, ...)
+{
+ mode_t mode = 0;
+
+ if (flags & O_CREAT) {
+ va_list args;
+
+ va_start(args, flags);
+ mode = va_arg(args, mode_t);
+ va_end(args);
+ }
+
+ return __sysret(sys_openat(dirfd, path, flags, mode));
+}
/*
* int open(const char *path, int flags[, mode_t mode]);
@@ -750,13 +797,7 @@ int mount(const char *src, const char *tgt,
static __attribute__((unused))
int sys_open(const char *path, int flags, mode_t mode)
{
-#ifdef __NR_openat
return my_syscall4(__NR_openat, AT_FDCWD, path, flags, mode);
-#elif defined(__NR_open)
- return my_syscall3(__NR_open, path, flags, mode);
-#else
- return __nolibc_enosys(__func__, path, flags, mode);
-#endif
}
static __attribute__((unused))
@@ -768,7 +809,7 @@ int open(const char *path, int flags, ...)
va_list args;
va_start(args, flags);
- mode = va_arg(args, int);
+ mode = va_arg(args, mode_t);
va_end(args);
}

tools/testing/selftests/kselftest.h

View file
diff --git a/tools/testing/selftests/kselftest.h b/tools/testing/selftests/kselftest.h
index cdf91b0..c3b6d26 100644
--- a/tools/testing/selftests/kselftest.h
+++ b/tools/testing/selftests/kselftest.h
@@ -444,10 +444,6 @@ static inline __noreturn __printf(1, 2) void ksft_exit_skip(const char *msg, ...
static inline int ksft_min_kernel_version(unsigned int min_major,
unsigned int min_minor)
{
-#ifdef NOLIBC
- ksft_print_msg("NOLIBC: Can't check kernel version: Function not implemented\n");
- return 0;
-#else
unsigned int major, minor;
struct utsname info;
@@ -455,7 +451,6 @@ static inline int ksft_min_kernel_version(unsigned int min_major,
ksft_exit_fail_msg("Can't parse kernel version\n");
return major > min_major || (major == min_major && minor >= min_minor);
-#endif
}
#endif /* __KSELFTEST_H */

tools/testing/selftests/nolibc/Makefile

View file
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 7d14a7c..58bcbbd 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -47,6 +47,7 @@ XARCH_riscv = riscv64
XARCH = $(or $(XARCH_$(ARCH)),$(ARCH))
# map from user input variants to their kernel supported architectures
+ARCH_armthumb = arm
ARCH_ppc = powerpc
ARCH_ppc64 = powerpc
ARCH_ppc64le = powerpc
@@ -54,6 +55,7 @@ ARCH_mips32le = mips
ARCH_mips32be = mips
ARCH_riscv32 = riscv
ARCH_riscv64 = riscv
+ARCH_s390x = s390
ARCH := $(or $(ARCH_$(XARCH)),$(XARCH))

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tools/testing/selftests/nolibc/nolibc-test-linkage.c

View file

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tools/testing/selftests/nolibc/nolibc-test.c

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tools/testing/selftests/nolibc/run-tests.sh

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