From: Greg Kurz <groug@kaod.org>
To: David Gibson <david@gibson.dropbear.id.au>
Cc: qemu-ppc@nongnu.org, qemu-devel@nongnu.org
Subject: [PATCH] spapr: Don't request to unplug the same core twice
Date: Wed, 23 Oct 2019 21:17:40 +0200 [thread overview]
Message-ID: <157185826035.3073024.1664101000438499392.stgit@bahia.lan> (raw)
We must not call spapr_drc_detach() on a detached DRC otherwise bad things
can happen, ie. QEMU hangs or crashes. This is easily demonstrated with
a CPU hotplug/unplug loop using QMP.
Signed-off-by: Greg Kurz <groug@kaod.org>
---
hw/ppc/spapr.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index f9410d390a07..94f9d27096af 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -3741,9 +3741,10 @@ void spapr_core_unplug_request(HotplugHandler *hotplug_dev, DeviceState *dev,
spapr_vcpu_id(spapr, cc->core_id));
g_assert(drc);
- spapr_drc_detach(drc);
-
- spapr_hotplug_req_remove_by_index(drc);
+ if (!spapr_drc_unplug_requested(drc)) {
+ spapr_drc_detach(drc);
+ spapr_hotplug_req_remove_by_index(drc);
+ }
}
int spapr_core_dt_populate(SpaprDrc *drc, SpaprMachineState *spapr,
next reply other threads:[~2019-10-23 20:05 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-23 19:17 Greg Kurz [this message]
2019-10-23 22:38 ` [PATCH] spapr: Don't request to unplug the same core twice David Gibson
2019-10-24 6:28 ` Greg Kurz
2019-10-28 22:20 ` David Gibson
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