Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
tools/nolibc: align sys_vfork() with sys_fork()
Currently the generic variants of sys_fork() and sys_vfork() differ in
both they precedence of used system calls and the usage of sys_clone()
vs sys_clone3(). While the interface of clone3() in sys_vfork() is more
consistent over different architectures, qemu-user does not support it,
making testing harder. We already handle the different clone()
interfaces for sys_fork() in the architecture-specific headers, and can
do so also for sys_vfork(). In fact SPARC already has such handling and
only s390 is currently missing.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260104-nolibc-vfork-v1-1-a63464b9e4e6@weissschuh.net
+13
-13
+8
tools/include/nolibc/arch-s390.h
+8
tools/include/nolibc/arch-s390.h
···
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#include "types.h"
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#include <linux/sched.h>
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#include <linux/signal.h>
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#include <linux/unistd.h>
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···
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return my_syscall5(__NR_clone, 0, SIGCHLD, 0, 0, 0);
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}
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#define sys_fork sys_fork
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static __attribute__((unused))
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pid_t sys_vfork(void)
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{
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return my_syscall5(__NR_clone, 0, CLONE_VM | CLONE_VFORK | SIGCHLD, 0, 0, 0);
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}
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#define sys_vfork sys_vfork
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#endif /* _NOLIBC_ARCH_S390_H */
+5
-13
tools/include/nolibc/sys.h
+5
-13
tools/include/nolibc/sys.h
···
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#include <linux/time.h>
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#include <linux/auxvec.h>
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#include <linux/fcntl.h> /* for O_* and AT_* */
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#include <linux/sched.h> /* for clone_args */
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#include <linux/sched.h> /* for CLONE_* */
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#include <linux/stat.h> /* for statx() */
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#include "errno.h"
···
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static __attribute__((unused))
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pid_t sys_vfork(void)
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{
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-
#if defined(__NR_vfork)
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#if defined(__NR_clone)
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/* See the note in sys_fork(). */
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return my_syscall5(__NR_clone, CLONE_VM | CLONE_VFORK | SIGCHLD, 0, 0, 0, 0);
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#elif defined(__NR_vfork)
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return my_syscall0(__NR_vfork);
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#else
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/*
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* clone() could be used but has different argument orders per
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* architecture.
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*/
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struct clone_args args = {
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.flags = CLONE_VM | CLONE_VFORK,
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.exit_signal = SIGCHLD,
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};
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return my_syscall2(__NR_clone3, &args, sizeof(args));
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#endif
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}
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#endif