Re: [PATCH 1/1] pci/pcie: refuse another hotplug/unplug event if attention button is pending

[Maxim Levitsky <mlevitsk@redhat.com>]

On Wed, 2020-07-22 at 19:19 +0300, Maxim Levitsky wrote:
> On Wed, 2020-07-22 at 19:17 +0300, Maxim Levitsky wrote:
> > Curently it is possible to hotplug a device and then immediatly
> > hotunplug it before the OS notices, and that will result
> > in missed unplug event since we can only send one attention button event.
> > 
> > Moreover the device will stuck in unplugging state forever.
> > 
> > Error out in such cases and rely on the caller (e.g libvirt) to retry
> > the unplug a bit later
> > 
> > Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
> > ---
> >  hw/pci/pcie.c | 11 +++++++++++
> >  1 file changed, 11 insertions(+)
> > 
> > diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
> > index 5b48bae0f6..9e836cf2f4 100644
> > --- a/hw/pci/pcie.c
> > +++ b/hw/pci/pcie.c
> > @@ -402,6 +402,17 @@ static void pcie_cap_slot_plug_common(PCIDevice *hotplug_dev, DeviceState *dev,
> >           */
> >          error_setg_errno(errp, EBUSY, "slot is electromechanically locked");
> >      }
> > +
> > +    if (sltsta & PCI_EXP_SLTSTA_ABP) {
> > +        /*
> > +         * Attention button is pressed, thus we can't send another
> > +         * hotpplug event
> Typo here, forgot to refresh the commit.
> > +         */
> > +        error_setg_errno(errp, EBUSY,
> > +                         "attention button is already pressed, can't "
> > +                         "send another hotplug event");
> > +    }
> > +
> >  }
> >  
> >  void pcie_cap_slot_pre_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
ping.


Best regards,
	Maxim Levitsky