[PATCH v2 1/8] acpi nvdimm: fix wrong buffer size returned by DSM method

[Xiao Guangrong <guangrong.xiao@linux.intel.com>]

Currently, 'RLEN' is the totally buffer size written by QEMU and it is
ACPI internally used only. The buffer size returned to guest should
not include 'RLEN' itself

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
---
 hw/acpi/nvdimm.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
index e486128..5454c0f 100644
--- a/hw/acpi/nvdimm.c
+++ b/hw/acpi/nvdimm.c
@@ -863,6 +863,8 @@ static void nvdimm_build_common_dsm(Aml *dev)
 
     result_size = aml_local(1);
     aml_append(method, aml_store(aml_name("RLEN"), result_size));
+    /* RLEN is not included in the payload returned to guest. */
+    aml_append(method, aml_subtract(result_size, aml_int(4), result_size));
     aml_append(method, aml_store(aml_shiftleft(result_size, aml_int(3)),
                                  result_size));
     aml_append(method, aml_create_field(aml_name("ODAT"), aml_int(0),
-- 
1.8.3.1