Re: Failed to hot-plug device to pxb bridge

["Michael S. Tsirkin" <mst@redhat.com>]

On Mon, Jun 24, 2024 at 03:08:55AM +0000, Gao,Shiyuan wrote:
> > I checked the guest dmesg and found that failed load shpc driver.
> >   [    0.966668] shpchp 0000:00:05.0: Requesting control of SHPC hotplug via OSHP (\_SB_.PCI0.S28_)
> >   [    0.968238] shpchp 0000:00:05.0: Requesting control of SHPC hotplug via OSHP (\_SB_.PCI0)
> >   [    0.969160] shpchp 0000:00:05.0: Cannot get control of SHPC hotplug
> >   [    0.969876] shpchp 0000:00:06.0: Requesting control of SHPC hotplug via OSHP (\_SB_.PCI0.S30_)
> >   [    0.971454] shpchp 0000:00:06.0: Requesting control of SHPC hotplug via OSHP (\_SB_.PCI0)
> >   [    0.972376] shpchp 0000:00:06.0: Cannot get control of SHPC hotplug
> >   [    0.973119] shpchp 0000:80:00.0: Requesting control of SHPC hotplug via OSHP (\_SB_.PC80)
> >   [    0.974674] shpchp 0000:80:00.0: Cannot get control of SHPC hotplug
> >   [    0.979422] shpchp 0000:81:01.0: Requesting control of SHPC hotplug via OSHP (\_SB_.PC80)
> >   [    0.980948] shpchp 0000:81:01.0: Cannot get control of SHPC hotplug
> >   [    0.981685] shpchp 0000:60:00.0: Requesting control of SHPC hotplug via OSHP (\_SB_.PC60)
> >   [    0.994623] shpchp 0000:60:00.0: Cannot get control of SHPC hotplug
> >   [    0.995349] shpchp 0000:61:01.0: Requesting control of SHPC hotplug via OSHP (\_SB_.PC60)
> >   [    0.996891] shpchp 0000:61:01.0: Cannot get control of SHPC hotplug
> >   [    0.997626] shpchp: Standard Hot Plug PCI Controller Driver version: 0.4
> > Read the shpc driver code, I found that before shpc_init it need check the shpc capability of bridge(shpc_capable) and
> > get hotplug control from firmware(acpi_get_hp_hw_control_from_firmware) in shpc_probe.
> > Howerver it return fail in acpi_get_hp_hw_control_from_firmware. I dump the acpid table, not found OSC and OSHP
> > method in dsdt.dsl.
> > In the QEMU build_dsdt, not found build osc method in i440fx.
> > Putting aside this pxb scenario, I suspect that after disable acpi-pci-hotplug-with-bridge-support,
> > hot-plug into the PCI bridge via SHPC can be successful in i440fx ?
> 
> After adding oshp method in build_dsdt, the SHPC driver load sucess and hotplug device sucess. Maybe we need a patch
> fix it ?
> 
> 
> 
> 

Sorry, can't really say what you are proposing.
Send a patch?