Comment 22 for bug 1849785

Arm64:
$ grep NR_open $(dpkg -L linux-libc-dev | xargs) 2>/dev/null
/usr/include/asm-generic/unistd.h:#define __NR_openat 56
/usr/include/asm-generic/unistd.h:__SYSCALL(__NR_openat, sys_openat)
/usr/include/asm-generic/unistd.h:#define __NR_open_by_handle_at 265
/usr/include/asm-generic/unistd.h:__SYSCALL(__NR_open_by_handle_at, sys_open_by_handle_at)
/usr/include/asm-generic/unistd.h:#define __NR_open_tree 428
/usr/include/asm-generic/unistd.h:__SYSCALL(__NR_open_tree, sys_open_tree)

Amd64:
$ grep NR_open $(dpkg -L linux-libc-dev | xargs) 2>/dev/null
/usr/include/asm-generic/unistd.h:#define __NR_openat 56
/usr/include/asm-generic/unistd.h:__SYSCALL(__NR_openat, sys_openat)
/usr/include/asm-generic/unistd.h:#define __NR_open_by_handle_at 265
/usr/include/asm-generic/unistd.h:__SYSCALL(__NR_open_by_handle_at, sys_open_by_handle_at)
/usr/include/asm-generic/unistd.h:#define __NR_open_tree 428
/usr/include/asm-generic/unistd.h:__SYSCALL(__NR_open_tree, sys_open_tree)
/usr/include/x86_64-linux-gnu/asm/unistd_32.h:#define __NR_open 5
/usr/include/x86_64-linux-gnu/asm/unistd_32.h:#define __NR_openat 295
/usr/include/x86_64-linux-gnu/asm/unistd_32.h:#define __NR_open_by_handle_at 342
/usr/include/x86_64-linux-gnu/asm/unistd_32.h:#define __NR_open_tree 428
/usr/include/x86_64-linux-gnu/asm/unistd_64.h:#define __NR_open 2
/usr/include/x86_64-linux-gnu/asm/unistd_64.h:#define __NR_openat 257
/usr/include/x86_64-linux-gnu/asm/unistd_64.h:#define __NR_open_by_handle_at 304
/usr/include/x86_64-linux-gnu/asm/unistd_64.h:#define __NR_open_tree 428
/usr/include/x86_64-linux-gnu/asm/unistd_x32.h:#define __NR_open (__X32_SYSCALL_BIT + 2)
/usr/include/x86_64-linux-gnu/asm/unistd_x32.h:#define __NR_openat (__X32_SYSCALL_BIT + 257)
/usr/include/x86_64-linux-gnu/asm/unistd_x32.h:#define __NR_open_by_handle_at (__X32_SYSCALL_BIT + 304)
/usr/include/x86_64-linux-gnu/asm/unistd_x32.h:#define __NR_open_tree (__X32_SYSCALL_BIT + 428)

So this really might be different on arm, not sure what to do about it yet.
Might be related to https://github.com/seccomp/libseccomp/commit/0db8babb27eed3ce202d54ec1cd99f23367631cf