Re: kern/80381: Mouse via KVM doesn't load on 5.4, does if plugged directly into mouse port.

Workaround Solution Found:

If you build a custom kernel 5.4 with

options KBD_RESETDELAY=401

it finds the mouse and loads properly at boot time with or without the 
KVM.   I guess there is something about the timing in 5.4 where it just 
doesn't take as long to reset the ps/2 mouse psm0 aux device with the same 
parameters as 5.3 did.  So a generic 5.3  kernel worked via the KVM setup 
but 5.4 on the same box required the specified amount of time to increase, 
so needs a custom kernel.

I suggest whoever is looking at the 5.4 release refer this change to the 
psm0 responsible party to consider making this change permanent.  It 
doesn't appreciably delay the boot process so far as I can tell.

Harry
---

I've found that 5.4 as of today won't load the psm0 driver if the box is 
connected through a KVM instead of directly to the mouse.

When I plug the mouse directly into the box, 5.4 and 5.3 load psm0 no 
problem.

When I plug the mouse in via the KVM, 5.4 won't load psm0 but 5.3 will.

If I plug the mouse in directly at boot time under 5.4, so psm0 loads, then 
(don't do this at home) hot-unplug it and plug in the kvm-- the mouse works 
via the KVM.

Hope this helps

Sincerely

Harry Coin