From aab99135b63522267c6fdae04712cb2f02c8c7de Mon Sep 17 00:00:00 2001 From: Bharata B Rao Date: Thu, 12 May 2016 09:18:21 +0530 Subject: spapr_drc: Prevent detach racing against attach for CPU DR 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 Reviewed-by: Michael Roth Signed-off-by: Michael Roth [Don't set awaiting_attach for PCI devices] Signed-off-by: David Gibson --- hw/ppc/spapr_drc.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'hw/ppc') diff --git a/hw/ppc/spapr_drc.c b/hw/ppc/spapr_drc.c index 94c875d..d276db3a 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; @@ -373,6 +375,10 @@ 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), @@ -421,6 +427,12 @@ 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) { -- cgit v1.1