Reintroduce the write callback that was removed when write support was
removed in commit 023e314856.
Contrary to the previous callback implementation, the write_cb
callback is called whenever a write happened, so handlers must be
ready to handle partial write as necessary.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This compat property sole function is to prevent the device from being
instantiated. Instead of requiring an extra compat property, check if
fw_cfg has DMA enabled.
fw_cfg is a built-in device that is initialized very early by the
machine init code. We have at least one other device that also
assumes fw_cfg_find() can be safely used on realize: pvpanic.
This has the additional benefit of handling other cases properly, like:
$ qemu-system-x86_64 -device vmgenid -machine none
qemu-system-x86_64: -device vmgenid: vmgenid requires DMA write support in fw_cfg, which this machine type does not provide
$ qemu-system-x86_64 -device vmgenid -machine pc-i440fx-2.9 -global fw_cfg.dma_enabled=off
qemu-system-x86_64: -device vmgenid: vmgenid requires DMA write support in fw_cfg, which this machine type does not provide
$ qemu-system-x86_64 -device vmgenid -machine pc-i440fx-2.6 -global fw_cfg.dma_enabled=on
[boots normally]
Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Ben Warren <ben@skyportsystems.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Moved vmgenid from uncategorized to misc category in QEMU help menu
Signed-off-by: Yoni Bettan <ybettan@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
A system with multiple VMGENID devices is undefined in the VMGENID spec by
omission.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Ben Warren <ben@skyportsystems.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
The WRITE_POINTER linker/loader command that underlies VMGENID depends on
commit baf2d5bfba ("fw-cfg: support writeable blobs", 2017-01-12), which
in turn depends on fw_cfg DMA.
DMA for fw_cfg is enabled in 2.5+ machine types only (see commit
e6915b5f3a, "fw_cfg: unbreak migration compatibility for 2.4 and earlier
machines", 2016-02-18).
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Ben Warren <ben@skyportsystems.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Ben Warren <ben@skyportsystems.com <mailto:ben@skyportsystems.com>>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
This was crashing due to NULL-pointer dereference
QMP Test case:
==============
(QEMU) query-vm-generation-id
{"error": {"class": "GenericError", "desc": "VM Generation ID device not
found"}}
HMP Test case:
==============
virsh # qemu-monitor-command --hmp 3 info vm-generation-id
VM Generation ID device not found
Signed-off-by: Ben Warren <ben@skyportsystems.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This implements the VM Generation ID feature by passing a 128-bit
GUID to the guest via a fw_cfg blob.
Any time the GUID changes, an ACPI notify event is sent to the guest
The user interface is a simple device with one parameter:
- guid (string, must be "auto" or in UUID format
xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx)
Signed-off-by: Ben Warren <ben@skyportsystems.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>