help: failed to decompress rpm files with rpm2cpio&cpio

[zhuizhuhaomeng]

I want to decompress the kernel-5.14.0-284.18.1.el9_2.aarch64.rpm with the following.
I can not decompress successfully.

rpm2cpio kernel-5.14.0-284.18.1.el9_2.aarch64.rpm | cpio -div
1 block

Then I ran rpm2cpio kernel-5.14.0-284.18.1.el9_2.aarch64.rpm > a.cpio.
I found the a.cpio only has 124 bytes.

What's the correct command to decompress the rpm file ?

[zhuizhuhaomeng]

I think the kernel-5.14.0-284.18.1.el9_2.aarch64.rpm contains no file.
But why the file is 3.5M. what is the content inside it?

[pmatilai]

rpm2cpio doesn't check for any rpmlib() dependencies the package may have, try 'rpm -i' on the src.rpm for that. Most likely the kernel package you're looking at is compressed with an algorithm (zstd) that the rpm you're using doesn't support.