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PID: 0.850
graphic: 0.770
performance: 0.692
device: 0.680
semantic: 0.663
network: 0.521
vnc: 0.482
socket: 0.465
files: 0.412
permissions: 0.404
debug: 0.390
boot: 0.362
other: 0.303
KVM: 0.077
qemu-user syscall clone fails
Description of problem:
This seems very similar to the issue reported here (https://bugs.launchpad.net/qemu/+bug/1926996). When attempting to perform the clone syscall, an error of -1 is returned where I would expect it to succeed. Running the same executable outside of qemu works as expected.
Steps to reproduce:
1. gcc clone.c
2. qemu-x86_64 a.out
Additional information:
I've tried building with gcc, zig cc, and clang and the output of each works fine when running natively, but running under qemu fails. I originally discovered it when cross compiling to riscv64 but it doesn't seem to be limited to that architecture.
```
// clone.c
#include <linux/sched.h>
#include <sched.h>
#include <sys/syscall.h>
#include <unistd.h>
#include <stdio.h>
int main(void) {
long pid = syscall( SYS_clone, 0, 0, 0, 0, 0 );
if (pid < 0) {
printf( "error %ld\n", pid );
} else if (pid == 0) {
printf( "child %ld\n", pid );
} else {
printf( "parent %ld\n", pid );
}
return 0;
}
```
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