From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46964) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fAkWH-0005Fa-8q for qemu-devel@nongnu.org; Mon, 23 Apr 2018 19:05:14 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fAkWE-0007tK-Eo for qemu-devel@nongnu.org; Mon, 23 Apr 2018 19:05:13 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:43636 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fAkWE-0007tG-9x for qemu-devel@nongnu.org; Mon, 23 Apr 2018 19:05:10 -0400 Date: Tue, 24 Apr 2018 02:05:09 +0300 From: "Michael S. Tsirkin" Message-ID: <20180424020443-mutt-send-email-mst@kernel.org> References: <20180423234259-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180423234259-mutt-send-email-mst@kernel.org> Subject: Re: [Qemu-devel] RFC: altering the NVDIMM acpi table List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Schmauss, Erik" Cc: "imammedo@redhat.com" , "qemu-devel@nongnu.org" , "Williams, Dan J" , "He, Junyan" , "Moore, Robert" On Mon, Apr 23, 2018 at 11:57:04PM +0300, Michael S. Tsirkin wrote: > On Mon, Apr 23, 2018 at 08:35:45PM +0000, Schmauss, Erik wrote: > > Hello, > > > > I work on ACPICA and we have recently made changes to the behavior of > > the Linux AML interpreter to match other OS implementations. After > > sending the patches to upstream Linux, we have identified that > > hw/acpi/nvdimm.c specifies an ACPI table with a forward reference > > (MEMA is a forward reference that is no longer supported as of Linux > > 4.17-rc1). > > Interesting. What is the result if such a table is encountered? > Will this break on old hypervisors that already > shipped with this set of tables? > > > We would like to change this file to move the declaration of Name > > (MEMA,...) to appear as the very first declaration in the SSDT. Below is a patch outlining the change that I would like to make. > > I think this will work just fine, but I would like to see a > comment explaining what the issue is. > Names aren't actually resolved until method actually runs, right? > For example, a name could be defined by a dynamically loaded > definition block ... > > > However, I am having a hard time getting make check to run > > to completion in a reasonable amount of time. It always seems to fail > > on some sort of checksum test... > > Are you running this on Linux? On bare metal or within a VM? > Most people here test it on Linux with KVM. In addition, isn't https://github.com/acpica/acpica/commit/0c08790c trying to fix exactly this configuration? > > It would be great if you could let me > > know what you think of the change and what I can do to speed up the > > execution time of make check... > > You could limit to just qtest tests. > > make check-qtest > > > > > Thanks, > > > > Erik Schmauss > > > > diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c > > index 59d6e4254c..7c9efd9ac7 100644 > > --- a/hw/acpi/nvdimm.c > > +++ b/hw/acpi/nvdimm.c > > @@ -1234,6 +1234,9 @@ static void nvdimm_build_ssdt(GArray *table_offsets, GArray *table_data, > > ssdt = init_aml_allocator(); > > acpi_data_push(ssdt->buf, sizeof(AcpiTableHeader)); > > > > + mem_addr_offset = build_append_named_dword(table_data, > > + NVDIMM_ACPI_MEM_ADDR); > > + > > sb_scope = aml_scope("\\_SB"); > > > > dev = aml_device("NVDR"); > > @@ -1266,9 +1269,6 @@ static void nvdimm_build_ssdt(GArray *table_offsets, GArray *table_data, > > > > /* copy AML table into ACPI tables blob and patch header there */ > > g_array_append_vals(table_data, ssdt->buf->data, ssdt->buf->len); > > - mem_addr_offset = build_append_named_dword(table_data, > > - NVDIMM_ACPI_MEM_ADDR); > > - > > bios_linker_loader_alloc(linker, > > NVDIMM_DSM_MEM_FILE, dsm_dma_arrea, > > sizeof(NvdimmDsmIn), false /* high memory */); > > > -- > MST