[PATCH 0/4] acpi: fix up EJ0 in DSDT

["Michael S. Tsirkin" <mst@redhat.com>]

Here's a bug: guest thinks it can eject VGA device and ISA bridge.

[root@dhcp74-172 ~]#lspci
00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev 02)
00:01.0 ISA bridge: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II]
00:01.1 IDE interface: Intel Corporation 82371SB PIIX3 IDE [Natoma/Triton II]
00:01.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 03)
00:02.0 VGA compatible controller: Cirrus Logic GD 5446
00:03.0 PCI bridge: Red Hat, Inc. Device 0001
00:04.0 Ethernet controller: Qumranet, Inc. Virtio network device
00:05.0 SCSI storage controller: Qumranet, Inc. Virtio block device
01:00.0 Ethernet controller: Intel Corporation 82540EM Gigabit Ethernet Controller (rev 03)

[root@dhcp74-172 ~]# ls /sys/bus/pci/slots/1/
adapter  address  attention  latch  module  power
[root@dhcp74-172 ~]# ls /sys/bus/pci/slots/2/
adapter  address  attention  latch  module  power

[root@dhcp74-172 ~]# echo 0 > /sys/bus/pci/slots/2/power 
[root@dhcp74-172 ~]# lspci
00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev 02)
00:01.0 ISA bridge: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II]
00:01.1 IDE interface: Intel Corporation 82371SB PIIX3 IDE [Natoma/Triton II]
00:01.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 03)
00:03.0 PCI bridge: Red Hat, Inc. Device 0001
00:04.0 Ethernet controller: Qumranet, Inc. Virtio network device
00:05.0 SCSI storage controller: Qumranet, Inc. Virtio block device
01:00.0 Ethernet controller: Intel Corporation 82540EM Gigabit Ethernet Controller (rev 03)

This is wrong because slots 1 and 2 are marked as not hotpluggable
in qemu.

The reason is that our acpi tables declare both _RMV with value 0,
and _EJ0 method for these slots. What happens in this case
is undocumented by ACPI spec, so linux ignores _RMV,
and windows seems to ignore _EJ0.

The correct way to suppress hotplug is not to have _EJ0,
so this is what this patch does: it probes PIIX and
modifies DSDT to match.

With these patches applied, we get:

[root@dhcp74-172 ~]# ls /sys/bus/pci/slots/1/
address
[root@dhcp74-172 ~]# ls /sys/bus/pci/slots/2/
address

I had to add a bit of compile-time infrastructure to handle the
runtime patching in a simple way. I expect that
it will be possible to reuse it if we need to
patch other methods in the future.

Michael S. Tsirkin (4):
  acpi: generate mixed asl/aml listing
  acpi: add aml/asl parsing script
  acpi: EJ0 method name patching
  acpi: remove _RMV

 Makefile          |   10 ++--
 src/acpi-dsdt.dsl |   58 +++--------------------
 src/acpi.c        |   11 ++++
 src/find_ej0.pl   |  136 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/splitdsl.pl   |   16 ++++++
 5 files changed, 176 insertions(+), 55 deletions(-)
 create mode 100755 src/find_ej0.pl
 create mode 100755 src/splitdsl.pl

-- 
1.7.5.53.gc233e