[PATCH 1/2] tools/nolibc: s390: provide custom implementation for sys_fork

From: Thomas Weißschuh
Date: Sat Apr 15 2023 - 17:28:58 EST


On s390 the first two arguments to the clone() syscall are swapped,
as documented in clone(2).

Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
---
tools/include/nolibc/arch-s390.h | 8 ++++++++
tools/include/nolibc/sys.h | 2 ++
2 files changed, 10 insertions(+)

diff --git a/tools/include/nolibc/arch-s390.h b/tools/include/nolibc/arch-s390.h
index 6b0e54ed543d..db4ea51a4dbb 100644
--- a/tools/include/nolibc/arch-s390.h
+++ b/tools/include/nolibc/arch-s390.h
@@ -5,6 +5,7 @@

#ifndef _NOLIBC_ARCH_S390_H
#define _NOLIBC_ARCH_S390_H
+#include <asm/signal.h>
#include <asm/unistd.h>

/* The struct returned by the stat() syscall, equivalent to stat64(). The
@@ -223,4 +224,11 @@ void *sys_mmap(void *addr, size_t length, int prot, int flags, int fd,
return (void *)my_syscall1(__NR_mmap, &args);
}
#define sys_mmap sys_mmap
+
+static __attribute__((unused))
+pid_t sys_fork(void)
+{
+ return my_syscall5(__NR_clone, 0, SIGCHLD, 0, 0, 0);
+}
+#define sys_fork sys_fork
#endif // _NOLIBC_ARCH_S390_H
diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h
index bea9760dbd16..f5a450153a63 100644
--- a/tools/include/nolibc/sys.h
+++ b/tools/include/nolibc/sys.h
@@ -336,6 +336,7 @@ void exit(int status)
* pid_t fork(void);
*/

+#ifndef sys_fork
static __attribute__((unused))
pid_t sys_fork(void)
{
@@ -351,6 +352,7 @@ pid_t sys_fork(void)
#error Neither __NR_clone nor __NR_fork defined, cannot implement sys_fork()
#endif
}
+#endif

static __attribute__((unused))
pid_t fork(void)

--
2.40.0