Unable to see the extensions cpu supports on vision five2

VisionFive 2 （English Forum)
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1

I am using fedora41 on my visionfive2 . when i run lscpu i see the flags are missing:

Architecture:           riscv64
  Byte Order:           Little Endian
CPU(s):                 4
  On-line CPU(s) list:  0-3
Vendor ID:              0x489
  Model name:           sifive,u74-mc
    CPU family:         0x8000000000000007
    Model:              0x4210427
    Thread(s) per core: 1
    Core(s) per socket: 4
    Socket(s):          1
    CPU(s) scaling MHz: 52%
    CPU max MHz:        1500.0000
    CPU min MHz:        312.5000
Caches (sum of all):    
  L1d:                  128 KiB (4 instances)
  L1i:                  128 KiB (4 instances)
  L2:                   2 MiB (1 instance)

How do i know what extensions does the cpu support ?.

2

I could see the extensions in cat /proc/cpuinfo, but like to know why lscpu doesn’t show these extensions under Flags