If hot add 100MiB memory like this: (monitor) object_add memory-backend-ram,id=ram0,size=100M (monitor) device_add pc-dimm,id=d0,memdev=ram0
The hotplug operation will faile, and the guest will print error message: Section-unaligned hotplug range: start 0x100000000, size 0x6400000 acpi PNP0C80:00: add_memory failed acpi PNP0C80:00: acpi_memory_enable_device() error Then I found that, according to the func check_hotplug_memory_range() in linux kernel, backend memory size must be multiple of 128MiB, not 2MiB. So this patch checks whether backend memory size is multiple of 128MiB. Signed-off-by: Zhu Guihua <zhugh.f...@cn.fujitsu.com> --- hw/mem/pc-dimm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c index d431834..3b8a015 100644 --- a/hw/mem/pc-dimm.c +++ b/hw/mem/pc-dimm.c @@ -161,9 +161,9 @@ uint64_t pc_dimm_get_free_addr(uint64_t address_space_start, goto out; } - if (QEMU_ALIGN_UP(size, align) != size) { + if (QEMU_ALIGN_UP(size, align * 64) != size) { error_setg(errp, "backend memory size must be multiple of 0x%" - PRIx64, align); + PRIx64, align * 64); goto out; } -- 1.9.3