Re: [RFC PATCH v2 0/4] Use ACPI PCI hot-plug for q35

[Igor Mammedov]

On Fri, 21 Aug 2020 12:30:07 +0200
Igor Mammedov <imammedo@redhat.com> wrote:

> On Tue, 18 Aug 2020 23:52:23 +0200
> Julia Suvorova <jusual@redhat.com> wrote:
> 
> > PCIe native hot-plug has numerous problems with racing events and 
> > unpredictable
> > guest behaviour (Windows).  
> Documenting these misterious problems I've asked for  in previous review
> hasn't been addressed.
> Pls see v1 for comments and add requested info into cover letter at least
> or in a commit message.
> 
> 
> > Switching to ACPI hot-plug for now.
in addition to above it looks like the way it's implemented,
it's either all on or all off.
Don't we want to have it per bridge?
What about per port that's possible with native.

We also should document (other than in C) expectations
toward this feature.

> > 
> > Tested on RHEL 8 and Windows 2019.
> > pxb-pcie is not yet supported.
> > 
> > v2:
> >     * new ioport range for acpiphp [Gerd]
> >     * drop find_pci_host() [Igor]
> >     * explain magic numbers in _OSC [Igor]
> >     * drop build_q35_pci_hotplug() wrapper [Igor]
> > 
> > Julia Suvorova (4):
> >   hw/acpi/ich9: Trace ich9_gpe_readb()/writeb()
> >   hw/i386/acpi-build: Add ACPI PCI hot-plug methods to q35
> >   hw/i386/acpi-build: Turn off support of PCIe native hot-plug and SHPC
> >     in _OSC
> >   hw/acpi/ich9: Enable ACPI PCI hot-plug
> > 
> >  hw/i386/acpi-build.h    | 12 ++++++++++
> >  include/hw/acpi/ich9.h  |  3 +++
> >  include/hw/acpi/pcihp.h |  3 ++-
> >  hw/acpi/ich9.c          | 52 ++++++++++++++++++++++++++++++++++++++++-
> >  hw/acpi/pcihp.c         | 15 ++++++++----
> >  hw/acpi/piix4.c         |  2 +-
> >  hw/i386/acpi-build.c    | 48 +++++++++++++++++++++++--------------
> >  hw/i386/pc.c            |  1 +
> >  hw/acpi/trace-events    |  4 ++++
> >  9 files changed, 114 insertions(+), 26 deletions(-)
> >   
> 
>