From c30a2c251e309eba40fd04e36b80016e4858c586 Mon Sep 17 00:00:00 2001 From: Serhii Popovych Date: Wed, 11 Jul 2018 17:11:45 +0100 Subject: [PATCH 2/4] Revert "spapr: Don't allow memory hotplug to memory less nodes" RH-Author: Serhii Popovych Message-id: <1531329105-80927-3-git-send-email-spopovyc@redhat.com> Patchwork-id: 81313 O-Subject: [RHEL-8.0 qemu-kvm PATCH 2/2] Revert "spapr: Don't allow memory hotplug to memory less nodes" Bugzilla: 1599593 RH-Acked-by: Laurent Vivier RH-Acked-by: David Gibson RH-Acked-by: Thomas Huth This reverts commit b556854bd8524c26b8be98ab1bfdf0826831e793. Leave change @node type from uint32_t to to int from reverted commit because node < 0 is always false. Note that implementing capability or some trick to detect if guest kernel does not support hot-add to memory: this returns previous behavour where memory added to first non-empty node. Signed-off-by: Serhii Popovych Signed-off-by: David Gibson (cherry picked from commit e47f1d2786c3d01a7894a493aafe0efa6b64453c) Signed-off-by: Serhii Popovych Signed-off-by: Danilo C. L. de Paula --- hw/ppc/spapr.c | 22 ---------------------- 1 file changed, 22 deletions(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index f3da93f..ef00937 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -3489,28 +3489,6 @@ static void spapr_machine_device_plug(HotplugHandler *hotplug_dev, return; } - /* - * Currently PowerPC kernel doesn't allow hot-adding memory to - * memory-less node, but instead will silently add the memory - * to the first node that has some memory. This causes two - * unexpected behaviours for the user. - * - * - Memory gets hotplugged to a different node than what the user - * specified. - * - Since pc-dimm subsystem in QEMU still thinks that memory belongs - * to memory-less node, a reboot will set things accordingly - * and the previously hotplugged memory now ends in the right node. - * This appears as if some memory moved from one node to another. - * - * So until kernel starts supporting memory hotplug to memory-less - * nodes, just prevent such attempts upfront in QEMU. - */ - if (nb_numa_nodes && !numa_info[node].node_mem) { - error_setg(errp, "Can't hotplug memory to memory-less node %d", - node); - return; - } - spapr_memory_plug(hotplug_dev, dev, node, errp); } else if (object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_CPU_CORE)) { spapr_core_plug(hotplug_dev, dev, errp); -- 1.8.3.1