[SeaBIOS] [RFC PATCH v4 00/30] ACPI memory hotplug
vasilis.liaskovitis at profitbricks.com
Tue Dec 18 13:41:28 CET 2012
This is v4 of the ACPI memory hotplug functionality. Only x86_64 target is
supported (both i440fx and q35). There are still several issues, but it's
been a while since v3 and I wanted to get some more feedback on the current
state of the patchseries.
Dimm device layout is modeled with a normal qemu device:
The starting physical address for all dimms is calculated from top of memory,
during memory controller init, skipping the pci hole at [PCI_HOLE_START, 4G).
will define a 512M memory dimm belonging to numa node 0, on bus membus.0.
Because dimm layout needs to be configured on machine-boot, all dimm devices
need to be specified on startup command line (either with populated=on or with
populated=off). The dimm information is stored in dimm configuration structures.
After machine startup, dimms are hot-added or removed with normal device_add
and device_del operations e.g.:
Hot-add syntax: "device_add dimm,id=mydimm0,bus=membus.0"
Hot-remove syntax: "device_del dimm,id=mydimm0"
- Dimms added with normal -device argument (extra -dimm arg dropped).
- multiple memory buses can be registered. Memory buses of the real hw/chipset
or a paravirtual memory bus can be added.
- acpi implementation uses memory API instead of old ioports.
- Support for q35/ich9 added (still buggy, see patch 12/31).
- piix4/i440fx initialization code has been refactored to resemble q35. This
will allow memory map initialization at chipset qdev init time for both
machines, as well as more similar code.
- Hot-remove functionality has been moved to separate patches. Hot-remove no
longer frees memory but unmaps the dimm/qdev device from the guest's view.
Freeing the memory should happen when the last user unrefs/unmaps the memory,
see also (work in progress):
- new qmp/hmp command for the state of each dimm (on/off)
- qdev integration. Dimms are attached to a dimmbus. The dimmbus is a child
of i440fx device in the pc machine. Hot-add and remove are done with normal
device_add / device_del operations on the dimmbus. New commands "dimm_add" and
"dimm_del" are obsolete.
- Add _PS3 method to allow OSPM-induced hot operations.
- pci-window calculation in Seabios takes dimms into account(for both 32-bit and
- rename new qmp commands: query-memory-total and query-memory-hotplug
- balloon driver can see the hotplugged memory
- memory map is automatically calculated for hotplug dimms. Dimms are added from
top-of-memory skipping the pci hole at [PCI_HOLE_START, 4G).
- Renamed from "-memslot" to "-dimm". Commands changed to "dimm_add", "dimm_del"
- Seabios ejection array reduced to a byte. Use extraction macros for dimm ssdt.
- additional SRAT paravirt info does not break previous SRAT fw_cfg layout.
- Documentation of new acpi_piix4 registers and paravirt data.
- add ACPI _OST support for _OST enabled guests. This allows qemu to receive
notification for success / failure of memory hot-add and hot-remove operations.
Guest needs to support _OST (https://lkml.org/lkml/2012/6/25/321)
- add monitor info command to report total guest memory (initial + hot-added)
- hot-remove needs to only unmap the dimm device from guest's view. Freeing the
memory should happen when the last user of the device (e.g. virtio-blk) unrefs
the device. A testcase is needed for this.
- Live Migration: Ramblocks are migrated before qdev VMStates are migrated. So
the DimmDevice is handled diferrently than other devices. Should this be
reworked ?( DimmDevice structure currently does not define a VMStateDescription)
Live migration works as long as the dimm layout (command line args) are
identical at the source and destination qemu command line, and destination takes
into account hot-operations that have occured on source. (v3 patch 10/19
created the DimmDevice that corresponds to an unknown incoming ramblock, e.g.
for a dimm that was hot-added on source. but has been dropped for the moment).
- A main blocker issue is windows guest functionality. The patchset does not
work for windows currently. Testing on win2012 server RC or windows2008
consumer prerelease, when adding a DIMM, there is a BSOD with ACPI_BIOS_ERROR
message. After this, the VM keeps rebooting with ACPI_BIOS_ERROR. The windows
pnpmem driver obviosuly has a problem with the seabios dimm implementation
(or the seabios dimm implementation is not fully ACPI-compliant). If someone
can review the seabios patches or has any ideas to debug this, let me know.
- hot-operation notification lists need to be added to migration state.
series is based on:
- qemu master (commit a8a826a3) + patch:
- seabios master (commit a810e4e7)
Can also be found at:
Vasilis Liaskovitis (21):
qapi: make visit_type_size fallback to type_int
Add SIZE type to qdev properties
qemu-option: export parse_option_number
Implement dimm device abstraction
vl: handle "-device dimm"
acpi_piix4 : Implement memory device hotplug registers
acpi_ich9 : Implement memory device hotplug registers
piix_pci and pc_piix: refactor
piix_pci: Add i440fx dram controller initialization
q35: Add i440fx dram controller initialization
pc: Add dimm paravirt SRAT info
Introduce paravirt interface QEMU_CFG_PCI_WINDOW
Implement "info memory-total" and "query-memory-total"
balloon: update with hotplugged memory
dimm: add hot-remove capability
acpi_piix4: add hot-remove capability
acpi_ich9: add hot-remove capability
Implement qmp and hmp commands for notification lists
Add _OST dimm support
Implement _PS3 for dimm
docs/specs/acpi_hotplug.txt | 54 ++++++
docs/specs/fwcfg.txt | 28 +++
hmp-commands.hx | 6 +
hmp.c | 41 ++++
hmp.h | 3 +
hw/Makefile.objs | 2 +-
hw/acpi.h | 5 +
hw/acpi_ich9.c | 115 +++++++++++-
hw/acpi_ich9.h | 12 +-
hw/acpi_piix4.c | 126 ++++++++++++-
hw/dimm.c | 444 +++++++++++++++++++++++++++++++++++++++++++
hw/dimm.h | 102 ++++++++++
hw/fw_cfg.h | 1 +
hw/lpc_ich9.c | 2 +-
hw/pc.c | 28 +++-
hw/pc.h | 1 +
hw/pc_piix.c | 74 ++++++--
hw/pc_q35.c | 18 ++-
hw/piix_pci.c | 249 ++++++++-----------------
hw/q35.c | 27 +++
hw/q35.h | 5 +
hw/qdev-properties.c | 60 ++++++
hw/qdev-properties.h | 3 +
hw/virtio-balloon.c | 13 +-
monitor.c | 21 ++
qapi-schema.json | 63 ++++++
qapi/qapi-visit-core.c | 11 +-
qemu-option.c | 4 +-
qemu-option.h | 4 +
qmp-commands.hx | 57 ++++++
sysemu.h | 1 +
vl.c | 60 ++++++
32 files changed, 1432 insertions(+), 208 deletions(-)
create mode 100644 docs/specs/acpi_hotplug.txt
create mode 100644 docs/specs/fwcfg.txt
create mode 100644 hw/dimm.c
create mode 100644 hw/dimm.h
Vasilis Liaskovitis (9):
Add ACPI_EXTRACT_DEVICE* macros
Add SSDT memory device support
acpi-dsdt: Implement functions for memory hotplug
acpi: generate hotplug memory devices
q35: Add memory hotplug handler
pci: Use paravirt interface for pcimem_start and pcimem64_start
acpi: add _EJ0 operation and eject port for memory devices
Add _OST dimm method
Implement _PS3 method for memory device
Makefile | 2 +-
src/acpi-dsdt-mem-hotplug.dsl | 136 +++++++++++++++++++++++++++++++++++
src/acpi-dsdt.dsl | 5 +-
src/acpi.c | 158 +++++++++++++++++++++++++++++++++++++++--
src/paravirt.c | 6 ++
src/paravirt.h | 2 +
src/pciinit.c | 9 +++
src/q35-acpi-dsdt.dsl | 6 +-
src/ssdt-mem.dsl | 73 +++++++++++++++++++
tools/acpi_extract.py | 28 +++++++
10 files changed, 415 insertions(+), 10 deletions(-)
create mode 100644 src/acpi-dsdt-mem-hotplug.dsl
create mode 100644 src/ssdt-mem.dsl
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