It doesn't even specify which "invalid syscall".
```
$ src/bitcoind -sandbox=log-and-abort
2022-02-17T13:45:57Z Bitcoin Core version v22.99.0-b223c3c21e89 (release build)
2022-02-17T13:45:57Z Assuming ancestors of block 00000000000000000008a89e854d57e5667df88f1cdef6fde2fbca1de5b639ad have valid signatures.
2022-02-17T13:45:57Z Setting nMinimumChainWork=00000000000000000000000000000000000000001fa4663bbbe19f82de910280
2022-02-17T13:45:57Z Experimental syscall sandbox enabled (-sandbox=log-and-abort): bitcoind will terminate if an unexpected (not allowlisted) syscall is invoked.
2022-02-17T13:45:57Z Using the 'sse4(1way),sse41(4way),avx2(8way)' SHA256 implementation
2022-02-17T13:45:57Z Default data directory /…/.bitcoin
2022-02-17T13:45:57Z Using data directory /…/.bitcoin
2022-02-17T13:45:57Z Config file: /…/.bitcoin/bitcoin.conf (not found, skipping)
2022-02-17T13:45:57Z Command-line arg: sandbox="log-and-abort"
2022-02-17T13:45:57Z Using at most 125 automatic connections (1024 file descriptors available)
2022-02-17T13:45:57Z Using 16 MiB out of 32/2 requested for signature cache, able to store 524288 elements
2022-02-17T13:45:57Z Using 16 MiB out of 32/2 requested for script execution cache, able to store 524288 elements
2022-02-17T13:45:57Z Script verification uses 1 additional threads
Bad system call (core dumped)
```
Nothing in `dmesg` either.
#define __NR_membarrier 324
#endif
#ifndef __NR_copy_file_range
#define __NR_copy_file_range 326
#endif
const std::map<uint32_t, std::string> LINUX_SYSCALLS{
    {__NR_accept, "accept"},
    {__NR_accept4, "accept4"},
    {__NR_access, "access"},
    {__NR_acct, "acct"},
    {__NR_add_key, "add_key"},
    {__NR_adjtimex, "adjtimex"},
    {__NR_afs_syscall, "afs_syscall"},
    {__NR_alarm, "alarm"},
    {__NR_arch_prctl, "arch_prctl"},
    {__NR_bind, "bind"},
    {__NR_bpf, "bpf"},
    {__NR_brk, "brk"},
    {__NR_capget, "capget"},
    {__NR_capset, "capset"},
    {__NR_chdir, "chdir"},
    {__NR_chmod, "chmod"},
    {__NR_chown, "chown"},
    {__NR_chroot, "chroot"},
    {__NR_clock_adjtime, "clock_adjtime"},
    {__NR_clock_getres, "clock_getres"},
    {__NR_clock_gettime, "clock_gettime"},
    {__NR_clock_nanosleep, "clock_nanosleep"},
    {__NR_clock_settime, "clock_settime"},
    {__NR_clone, "clone"},