| Message ID | 1463024905-28401-12-git-send-email-bharata@linux.vnet.ibm.com |
|---|---|
| State | New |
| Headers | show |
On Thu, May 12, 2016 at 09:18:21AM +0530, Bharata B Rao wrote: > If a CPU is hot removed while hotplug of the same is still in progress, > the guest crashes. Prevent this by ensuring that detach is done only > after attach has completed. > > The existing code already prevents such race for PCI hotplug. However > given that CPU is a logical DR unlike PCI and starts with ISOLATED > state, we need a logic that works for CPU too. > > Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> > Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com> > Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com> > [Don't set awaiting_attach for PCI devices] Applied to ppc-cpu-hotplug branch. > --- > hw/ppc/spapr_drc.c | 12 ++++++++++++ > include/hw/ppc/spapr_drc.h | 1 + > 2 files changed, 13 insertions(+) > > diff --git a/hw/ppc/spapr_drc.c b/hw/ppc/spapr_drc.c > index 1f5f1d7..e146267 100644 > --- a/hw/ppc/spapr_drc.c > +++ b/hw/ppc/spapr_drc.c > @@ -140,6 +140,8 @@ static uint32_t set_allocation_state(sPAPRDRConnector *drc, > DPRINTFN("finalizing device removal"); > drck->detach(drc, DEVICE(drc->dev), drc->detach_cb, > drc->detach_cb_opaque, NULL); > + } else if (drc->allocation_state == SPAPR_DR_ALLOCATION_STATE_USABLE) { > + drc->awaiting_allocation = false; > } > } > return RTAS_OUT_SUCCESS; > @@ -376,6 +378,10 @@ static void attach(sPAPRDRConnector *drc, DeviceState *d, void *fdt, > drc->signalled = (drc->type != SPAPR_DR_CONNECTOR_TYPE_PCI) > ? true : coldplug; > > + if (drc->type != SPAPR_DR_CONNECTOR_TYPE_PCI) { > + drc->awaiting_allocation = true; > + } > + > object_property_add_link(OBJECT(drc), "device", > object_get_typename(OBJECT(drc->dev)), > (Object **)(&drc->dev), > @@ -424,6 +430,12 @@ static void detach(sPAPRDRConnector *drc, DeviceState *d, > return; > } > > + if (drc->awaiting_allocation) { > + drc->awaiting_release = true; > + DPRINTFN("awaiting allocation to complete before removal"); > + return; > + } > + > drc->indicator_state = SPAPR_DR_INDICATOR_STATE_INACTIVE; > > if (drc->detach_cb) { > diff --git a/include/hw/ppc/spapr_drc.h b/include/hw/ppc/spapr_drc.h > index fa21ba0..08e8411 100644 > --- a/include/hw/ppc/spapr_drc.h > +++ b/include/hw/ppc/spapr_drc.h > @@ -152,6 +152,7 @@ typedef struct sPAPRDRConnector { > > bool awaiting_release; > bool signalled; > + bool awaiting_allocation; > > /* device pointer, via link property */ > DeviceState *dev;
diff --git a/hw/ppc/spapr_drc.c b/hw/ppc/spapr_drc.c index 1f5f1d7..e146267 100644 --- a/hw/ppc/spapr_drc.c +++ b/hw/ppc/spapr_drc.c @@ -140,6 +140,8 @@ static uint32_t set_allocation_state(sPAPRDRConnector *drc, DPRINTFN("finalizing device removal"); drck->detach(drc, DEVICE(drc->dev), drc->detach_cb, drc->detach_cb_opaque, NULL); + } else if (drc->allocation_state == SPAPR_DR_ALLOCATION_STATE_USABLE) { + drc->awaiting_allocation = false; } } return RTAS_OUT_SUCCESS; @@ -376,6 +378,10 @@ static void attach(sPAPRDRConnector *drc, DeviceState *d, void *fdt, drc->signalled = (drc->type != SPAPR_DR_CONNECTOR_TYPE_PCI) ? true : coldplug; + if (drc->type != SPAPR_DR_CONNECTOR_TYPE_PCI) { + drc->awaiting_allocation = true; + } + object_property_add_link(OBJECT(drc), "device", object_get_typename(OBJECT(drc->dev)), (Object **)(&drc->dev), @@ -424,6 +430,12 @@ static void detach(sPAPRDRConnector *drc, DeviceState *d, return; } + if (drc->awaiting_allocation) { + drc->awaiting_release = true; + DPRINTFN("awaiting allocation to complete before removal"); + return; + } + drc->indicator_state = SPAPR_DR_INDICATOR_STATE_INACTIVE; if (drc->detach_cb) { diff --git a/include/hw/ppc/spapr_drc.h b/include/hw/ppc/spapr_drc.h index fa21ba0..08e8411 100644 --- a/include/hw/ppc/spapr_drc.h +++ b/include/hw/ppc/spapr_drc.h @@ -152,6 +152,7 @@ typedef struct sPAPRDRConnector { bool awaiting_release; bool signalled; + bool awaiting_allocation; /* device pointer, via link property */ DeviceState *dev;