illumos gate

As with most bhyve changes, the first test procedure was to confirm that a variety of operating systems would still boot and run on a platform featuring the change. This was done on both AMD and Intel systems. Using dtrace, I could confirm that the PM timer handler (vpmtmr_handler) attached to the IO port in question was still being called when the guest initiated accesses to the port. The only external driver consumer, viona, was also able to attach its IO port hook and drive network traffic as expected. Using the newly-added --pmtmr-port feature in bhyvectl, I could move the PM timer port around to different addresses and verify that it wouldn't overlay an existing port handler or stumble over other "odd" conditions.

I was also able to manually confirm (via mdb -k) that the port hooks for a given instance looked correct and normal:

> vmm_list::walk list | ::print vmm_softc_t vmm_vm | ::print 'struct vm' ioports.iop_entries | ::eval '.,f::print ioport_entry_t'
{
    iope_func = vatpic_master_handler
    iope_arg = 0xfffffe59dd024180
    iope_port = 0x20
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vatpic_master_handler
    iope_arg = 0xfffffe59dd024180
    iope_port = 0x21
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vatpit_handler
    iope_arg = 0xfffffe5a2c125e00
    iope_port = 0x40
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vatpit_handler
    iope_arg = 0xfffffe5a2c125e00
    iope_port = 0x41
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vatpit_handler
    iope_arg = 0xfffffe5a2c125e00
    iope_port = 0x42
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vatpit_handler
    iope_arg = 0xfffffe5a2c125e00
    iope_port = 0x43
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vatpit_nmisc_handler
    iope_arg = 0xfffffe5a2c125e00
    iope_port = 0x61
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vrtc_addr_handler
    iope_arg = 0xfffffe59d0c16510
    iope_port = 0x70
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vrtc_data_handler
    iope_arg = 0xfffffe59d0c16510
    iope_port = 0x71
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vatpic_slave_handler
    iope_arg = 0xfffffe59dd024180
    iope_port = 0xa0
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vatpic_slave_handler
    iope_arg = 0xfffffe59dd024180
    iope_port = 0xa1
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vpmtmr_handler
    iope_arg = 0xfffffe5a0c9e1bd8
    iope_port = 0x408
    iope_flags = 0
    iope_pad = 0
}
{
    iope_func = vatpic_elc_handler
    iope_arg = 0xfffffe59dd024180
    iope_port = 0x4d0
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = vatpic_elc_handler
    iope_arg = 0xfffffe59dd024180
    iope_port = 0x4d1
    iope_flags = 0x1
    iope_pad = 0
}
{
    iope_func = viona_notify_iop
    iope_arg = 0xfffffe5a91a77b80
    iope_port = 0x2090
    iope_flags = 0x2
    iope_pad = 0
}

Mike Zeller successfully tested this (along with a few other bhyve patches) under SmartOS on an AMD Epyc machine.