My eBPF program as follows.

#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_endian.h>
#include <bpf/bpf_tracing.h>
#include <bpf/bpf_core_read.h>
#include "common.h"

char __license[] SEC("license") = "GPL";

SEC("sockops")
int bpf_sockops_cb(struct bpf_sock_ops *skops) {
    u32 op;

    int err;

    err = bpf_core_read(&op, sizeof(op), &skops->op);
    if (err) {
        bpf_printk("errn");
    }

    bpf_printk("op1 = %u, op2 = %u n", op, skops->op);

    return 0;
}

When I check the tracing output by cat /sys/kernel/debug/tracing/trace_pipe, it shows that op1 != op2.

curl-1466326 [009] ....1 241519.609044: bpf_trace_printk: op1 = 3913290112, op2 = 3 

            curl-1466326 [009] ....1 241519.609048: bpf_trace_printk: op1 = 3913290112, op2 = 2 

            curl-1466326 [009] ....1 241519.609048: bpf_trace_printk: op1 = 3913290112, op2 = 1 

            curl-1466326 [009] ....1 241519.609049: bpf_trace_printk: op1 = 3913290112, op2 = 6

Why does op1 and op2 become different ?