CXL Namespaces of ACPI disappearing in Qemu demo

[Yuquan Wang]

Hi, Jonathan

When I tested the CXL topology in qemu, I found the linux kernel could find 

and match the ACPI0016&ACPI0017 in relevant drivers, however, I could not 

find these information in dumped ACPI tables (like DSDT). 

Hence, I guess there is some problem in my method, maybe you have some 

suggestions if you have some time to look at this email.

My environment:

qemu: Jonathan_qemu/cxl-2023-08-07

Linux: v6.3.0

ACPI Disassembler: iasl/version 20230628

My qemu script is the same as the first example in qemu/docs/system/devices/cxl.rst, 

as below:

  qemu-system-x86_64 -M q35,cxl=on -m 4G,maxmem=8G,slots=8 -smp 4 \
  ...
  -object memory-backend-file,id=cxl-mem1,share=on,mem-path=/tmp/cxltest.raw,size=256M \
  -object memory-backend-file,id=cxl-lsa1,share=on,mem-path=/tmp/lsa.raw,size=256M \
  -device pxb-cxl,bus_nr=12,bus=pcie.0,id=cxl.1 \
  -device cxl-rp,port=0,bus=cxl.1,id=root_port13,chassis=0,slot=2 \
  -device cxl-type3,bus=root_port13,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem0 \
  -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.size=4G

Many thanks

Yuquan