kernel 5.10.x Reserves much more RAM than 5.11.0, 8 MB vs 20 MB

Joakim Tjernlund <Joakim.Tjernlund@xxxxxxxxxxxx> · Wed, 27 Oct 2021 12:48:13 +0000

Using a fairly minimal kernel I get a big difference in Reserved memory, using:
    qemu-system-aarch64 -machine virt -kernel arch/arm64/boot/Image -cpu cortex-a53  -nographic -m 32M

I get this:
Linux version 5.11.0
Memory: 24052K/32768K available (3520K kernel code, 684K rwdata, 548K rodata, 320K init, 245K bss, 8716K reserved, 0K cma-reserved)

Versus:

Linux version 5.10.75
Memory: 11836K/32768K available (3518K kernel code, 684K rwdata, 540K rodata, 320K init, 244K bss, 20932K reserved, 0K cma-reserved)

Reserving 20 MB RAM on a 32 MB is way too much, even 8Mb is a bit much for us.

 Jocke

PS. I hope this is the right list, please advise if it is not.