Not only qemu-x86_64, but also:
qemu-aarch64 => qemu: Unsupported syscall: 279 qemu-arm => qemu: Unsupported syscall: 385 qemu-mips => qemu: Unsupported syscall: 4354 qemu-mips64 => qemu: Unsupported syscall: 5314 qemu-powerpc => qemu: Unsupported syscall: 360 qemu-powerpc64 => qemu: Unsupported syscall: 360
Not only qemu-x86_64, but also:
qemu-aarch64 => qemu: Unsupported syscall: 279
qemu-arm => qemu: Unsupported syscall: 385
qemu-mips => qemu: Unsupported syscall: 4354
qemu-mips64 => qemu: Unsupported syscall: 5314
qemu-powerpc => qemu: Unsupported syscall: 360
qemu-powerpc64 => qemu: Unsupported syscall: 360