From 3fad87881e55aaff659408dcf25fa204f89a7896 Mon Sep 17 00:00:00 2001 From: Igor Mammedov Date: Tue, 6 Oct 2015 10:37:28 +0200 Subject: [PATCH] pc-dimm: add vhost slots limit check before commiting to hotplug it allows safely cancel memory hotplug if vhost backend doesn't support necessary amount of memory slots and prevents QEMU crashing in vhost due to hitting vhost limit on amount of supported memory ranges. Signed-off-by: Igor Mammedov Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/mem/pc-dimm.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c index 506fe0d..2bae994 100644 --- a/hw/mem/pc-dimm.c +++ b/hw/mem/pc-dimm.c @@ -25,6 +25,7 @@ #include "sysemu/numa.h" #include "sysemu/kvm.h" #include "trace.h" +#include "hw/virtio/vhost.h" typedef struct pc_dimms_capacity { uint64_t size; @@ -96,6 +97,12 @@ void pc_dimm_memory_plug(DeviceState *dev, MemoryHotplugState *hpms, goto out; } + if (!vhost_has_free_slot()) { + error_setg(&local_err, "a used vhost backend has no free" + " memory slots left"); + goto out; + } + memory_region_add_subregion(&hpms->mr, addr - hpms->base, mr); vmstate_register_ram(mr, dev); numa_set_mem_node_id(addr, memory_region_size(mr), dimm->node); -- 2.7.4