qemu/include/hw/hyperv, branch master

vmbus: Print a warning when enabled without the recommended set of features

2024-03-08T13:18:56Z

Some Windows versions crash at boot or fail to enable the VMBus device if they don't see the expected set of Hyper-V features (enlightenments). Since this provides poor user experience let's warn user if the VMBus device is enabled without the recommended set of Hyper-V features. The recommended set is the minimum set of Hyper-V features required to make the VMBus device work properly in Windows Server versions 2016, 2019 and 2022. Acked-by: Paolo Bonzini Signed-off-by: Maciej S. Szmigiero

hv-balloon: define dm_hot_add_with_region to avoid Coverity warning

2024-03-08T13:18:56Z

Since the presence of a hot add memory region is optional in hot add request message it wasn't part of this message declaration (struct dm_hot_add). Instead, the code allocated such enlarged message by simply adding the necessary size for this extra field to the size of basic hot add message struct. However, Coverity considers accessing this extra member to be an out-of-bounds access, even thought the memory is actually there. Fix this by adding an extended variant of this message that explicitly has an additional union dm_mem_page_range at its end. CID: #1523903 Signed-off-by: Maciej S. Szmigiero

include/hw/hyperv/dynmem-proto.h: spelling fix: nunber, atleast

2023-11-15T09:06:05Z

Fixes: 4f80cd2f033e "Add Hyper-V Dynamic Memory Protocol definitions" Acked-by: Maciej S. Szmigiero Signed-off-by: Michael Tokarev

Add Hyper-V Dynamic Memory Protocol driver (hv-balloon) base

2023-11-06T13:08:10Z

This driver is like virtio-balloon on steroids: it allows both changing the guest memory allocation via ballooning and (in the next patch) inserting pieces of extra RAM into it on demand from a provided memory backend. The actual resizing is done via ballooning interface (for example, via the "balloon" HMP command). This includes resizing the guest past its boot size - that is, hot-adding additional memory in granularity limited only by the guest alignment requirements, as provided by the next patch. In contrast with ACPI DIMM hotplug where one can only request to unplug a whole DIMM stick this driver allows removing memory from guest in single page (4k) units via ballooning. After a VM reboot the guest is back to its original (boot) size. In the future, the guest boot memory size might be changed on reboot instead, taking into account the effective size that VM had before that reboot (much like Hyper-V does). For performance reasons, the guest-released memory is tracked in a few range trees, as a series of (start, count) ranges. Each time a new page range is inserted into such tree its neighbors are checked as candidates for possible merging with it. Besides performance reasons, the Dynamic Memory protocol itself uses page ranges as the data structure in its messages, so relevant pages need to be merged into such ranges anyway. One has to be careful when tracking the guest-released pages, since the guest can maliciously report returning pages outside its current address space, which later clash with the address range of newly added memory. Similarly, the guest can report freeing the same page twice. The above design results in much better ballooning performance than when using virtio-balloon with the same guest: 230 GB / minute with this driver versus 70 GB / minute with virtio-balloon. During a ballooning operation most of time is spent waiting for the guest to come up with newly freed page ranges, processing the received ranges on the host side (in QEMU and KVM) is nearly instantaneous. The unballoon operation is also pretty much instantaneous: thanks to the merging of the ballooned out page ranges 200 GB of memory can be returned to the guest in about 1 second. With virtio-balloon this operation takes about 2.5 minutes. These tests were done against a Windows Server 2019 guest running on a Xeon E5-2699, after dirtying the whole memory inside guest before each balloon operation. Using a range tree instead of a bitmap to track the removed memory also means that the solution scales well with the guest size: even a 1 TB range takes just a few bytes of such metadata. Since the required GTree operations aren't present in every Glib version a check for them was added to the meson build script, together with new "--enable-hv-balloon" and "--disable-hv-balloon" configure arguments. If these GTree operations are missing in the system's Glib version this driver will be skipped during QEMU build. An optional "status-report=on" device parameter requests memory status events from the guest (typically sent every second), which allow the host to learn both the guest memory available and the guest memory in use counts. Following commits will add support for their external emission as "HV_BALLOON_STATUS_REPORT" QMP events. The driver is named hv-balloon since the Linux kernel client driver for the Dynamic Memory Protocol is named as such and to follow the naming pattern established by the virtio-balloon driver. The whole protocol runs over Hyper-V VMBus. The driver was tested against Windows Server 2012 R2, Windows Server 2016 and Windows Server 2019 guests and obeys the guest alignment requirements reported to the host via DM_CAPABILITIES_REPORT message. Acked-by: David Hildenbrand Signed-off-by: Maciej S. Szmigiero

Add Hyper-V Dynamic Memory Protocol definitions

2023-11-06T12:54:57Z

This commit adds Hyper-V Dynamic Memory Protocol definitions, taken from hv_balloon Linux kernel driver, adapted to the QEMU coding style and definitions. Acked-by: David Hildenbrand Signed-off-by: Maciej S. Szmigiero

include/: spelling fixes

2023-09-08T10:08:52Z

Signed-off-by: Michael Tokarev Reviewed-by: Alex Bennée

hw/hyperv/vmbus: Remove unused vmbus_load/save_req()

2022-05-30T17:49:42Z

vmbus_save_req() and vmbus_load_req() are not used. Remove them to avoid maintaining dead code. This essentially reverts commit 4dd8a7064b8a6527f99a62be11 ("vmbus: add infrastructure to save/load vmbus requests"). Signed-off-by: Philippe Mathieu-Daudé Message-Id: <20211106134155.582312-2-philmd@redhat.com> [MSS: Remove also corresponding variables, which are now unused] Signed-off-by: Maciej S. Szmigiero

hyperv: Add support to process syndbg commands

2022-04-06T12:31:56Z

SynDbg commands can come from two different flows: 1. Hypercalls, in this mode the data being sent is fully encapsulated network packets. 2. SynDbg specific MSRs, in this mode only the data that needs to be transfered is passed. Signed-off-by: Jon Doron Reviewed-by: Emanuele Giuseppe Esposito Message-Id: <20220216102500.692781-4-arilou@gmail.com> Signed-off-by: Paolo Bonzini

hyperv: Add definitions for syndbg

2022-04-06T12:31:56Z

Add all required definitions for hyperv synthetic debugger interface. Signed-off-by: Jon Doron Reviewed-by: Emanuele Giuseppe Esposito Message-Id: <20220216102500.692781-3-arilou@gmail.com> Signed-off-by: Paolo Bonzini

Use OBJECT_DECLARE_SIMPLE_TYPE when possible

2020-09-18T18:12:32Z

This converts existing DECLARE_INSTANCE_CHECKER usage to OBJECT_DECLARE_SIMPLE_TYPE when possible. $ ./scripts/codeconverter/converter.py -i \ --pattern=AddObjectDeclareSimpleType $(git grep -l '' -- '*.[ch]') Signed-off-by: Eduardo Habkost Acked-by: Paul Durrant Message-Id: <20200916182519.415636-6-ehabkost@redhat.com> Signed-off-by: Eduardo Habkost