[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references
From: |
Michael S. Tsirkin |
Subject: |
Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references |
Date: |
Tue, 24 Apr 2018 20:43:22 +0300 |
On Tue, Apr 24, 2018 at 09:57:22AM +0200, Igor Mammedov wrote:
> On Tue, 24 Apr 2018 04:02:40 +0300
> "Michael S. Tsirkin" <address@hidden> wrote:
>
> > On Tue, Apr 24, 2018 at 12:41:29AM +0000, Schmauss, Erik wrote:
> > >
> > >
> > > > -----Original Message-----
> > > > From: Michael S. Tsirkin [mailto:address@hidden
> > > > Sent: Monday, April 23, 2018 4:03 PM
> > > > To: address@hidden
> > > > Cc: Schmauss, Erik <address@hidden>; Igor Mammedov
> > > > <address@hidden>; Xiao Guangrong <address@hidden>
> > > > Subject: [PATCH] acpi/nvdimm: remove forward name references
> > > >
> > > > NVDIMM SSDT table references a name ("MEMA") before it is defined. This
> > > > is
> > > > reported to no longer be supported since Linux 4.17-rc1.
> > > >
> > > > While arguably Linux needs to keep working on old hypervisors, and
> > > > other OSes
> > > > seem fine with our behaviour, it seems cleaner to have the definition
> > > > appear in
> > > > the SSDT before use.
> > > >
> > > > Suggested-by: "Schmauss, Erik" <address@hidden>
> > > > Cc: address@hidden
> > > > Signed-off-by: Michael S. Tsirkin <address@hidden>
> > > > ---
> > > >
> > > > Hi Erik,
> > > > could you pls test the issue and report whether it addresses your
> > > > concern? I can't
> > > Hi Michael,
> > >
> > > > do much to fix past releases which IIUC shipped this code since 2.6.0
> > > > about a
> > > > year ago.
> > > >
> > > > Lightly tested with Linux only.
> > >
> > > I'm looking at the ASL tables generated by make check-qtest-x86_64.
> > > This line
> >
> > which line?
> >
> > > ends up generating a strange ACPI table where the Operation
> > > region and field declarations are stuck inside the NCAL method which
> > > is called from _DSM. If we create the operation region and methods
> > > inside methods, they disappear after the NCAL method returns.
> What's wrong with it?
> Method is complete so temporary objects
> it has used went out of scope, all within spec rules
> and worked fine with linux and windows guests.
>
> > > I think nvdimm_build_common_dsm() needs some refining.
> >
> > What exactly do you refer to?
> >
> > DefinitionBlock ("", "SSDT", 1, "BOCHS ", "NVDIMM", 0x00000001)
> > {
> > Name (MEMA, 0x07FFE000)
> > Scope (\_SB)
> > {
> > Device (NVDR)
> > {
> > Name (_HID, "ACPI0012" /* NVDIMM Root Device */) // _HID:
> > Hardware ID
> > Method (NCAL, 5, Serialized)
> > {
> > Local6 = MEMA /* \MEMA */
> > OperationRegion (NPIO, SystemIO, 0x0A18, 0x04)
> > OperationRegion (NRAM, SystemMemory, Local6, 0x1000)
> >
> > ^^^ this?
> >
> > I agree the NPIO could be moved out.
> > Don't really understand why is Local6 needed - can't MEMA be
> > used directly? Assuming it isn't NRAM could be moved out too.
> From spec
> DefOpRegion := OpRegionOp NameString RegionSpace RegionOffset RegionLen
> RegionOffset := TermArg => Integer
> TermArg := Type2Opcode | DataObject | ArgObj | LocalObj
>
> So named object is not accepted,
might be worth checking what happens with actual OSPMs.
If it does happen to work, we can try tweaking the ACPI
spec to allow this.
> we could have played games with
> references and Type2Opcode but that didn't work nice with Windows
> ACPI parser. Hence local object.
A comment in code wouldn't hurt to explain this.
> The reason why OperationRegion is dynamic, is that if we put it
> outside of method it will become static, and we would have to use
> Integer constant there (no named objects are allowed) and
> then patch it dynamically in bios loader.
> I'd prefer to keep it as is, without introducing another hack
> like build_append_named_operation_region() to create it with
> know offset so firmware could patch it.
I agree to that.
> >
> >
> > It all seems suboptimal but given the method is serialized,
> > I don't see anything wrong with it as such.
> >
> >
> > >
> > > >
> > > > hw/acpi/nvdimm.c | 6 ++++--
> > > > 1 file changed, 4 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c index 59d6e42..fadebbd
> > > > 100644
> > > > --- a/hw/acpi/nvdimm.c
> > > > +++ b/hw/acpi/nvdimm.c
> > > > @@ -1234,6 +1234,10 @@ static void nvdimm_build_ssdt(GArray
> > > > *table_offsets,
> > > > GArray *table_data,
> > > > ssdt = init_aml_allocator();
> > > > acpi_data_push(ssdt->buf, sizeof(AcpiTableHeader));
> > > >
> > > > + /* Storage for the memory address */
> > > > + mem_addr_offset = table_data->len +
> > > > + build_append_named_dword(ssdt->buf, NVDIMM_ACPI_MEM_ADDR);
> > > > +
> > > > sb_scope = aml_scope("\\_SB");
> > > >
> > > > dev = aml_device("NVDR");
> > > > @@ -1266,8 +1270,6 @@ 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,
> > > > --
> > > > MST
- [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Michael S. Tsirkin, 2018/04/23
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Schmauss, Erik, 2018/04/23
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Michael S. Tsirkin, 2018/04/23
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Igor Mammedov, 2018/04/24
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references,
Michael S. Tsirkin <=
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Schmauss, Erik, 2018/04/24
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Michael S. Tsirkin, 2018/04/24
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Igor Mammedov, 2018/04/25
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Igor Mammedov, 2018/04/25
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Michael S. Tsirkin, 2018/04/25
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Igor Mammedov, 2018/04/25
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Schmauss, Erik, 2018/04/25
- Re: [Qemu-devel] [PATCH] acpi/nvdimm: remove forward name references, Dan Williams, 2018/04/25