Khelp module "ertt" can't unload until its refcount drops from 4 to 0

Hello arm@,

I see this just when my 14-current rpi4 reboots

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Uptime: 6d9h12m34s
Khelp module "ertt" can't unload until its refcount drops from 4 to 0.
Resetting system ...
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The closest I could find to it was h_ertt(4) mentioned in man khelp
This led me to look at sysctl net.inet.tcp.cc.algorithm

I notice that net.inet.tcp.cc.algorithm=cubic in 14-current but it's
newreno in 13-stable. 

Does it need a PR, and if so, where? 

TIA,
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