summaryrefslogtreecommitdiff
path: root/Documentation/virt/hyperv
AgeCommit message (Collapse)Author
11 daysDocumentation: hyperv: Update information on guest CPU offliningMichael Kelley
In Hyper-V Overview documentation, remove the out-of-date reference to explicitly reassigning VMBus channel interrupts before taking a guest CPU offline. Instead, reference the VMBus documentation, which is already up-to-date on this topic. Signed-off-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Naman Jain <namjain@linux.microsoft.com> Reviewed-by: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
11 daysDocumentation: hyperv: Remove support for guests on Hyper-V 2012/2012R2Michael Kelley
Support for running Linux guests on Windows Server 2012/2012 R2 Hyper-V hosts and Windows 8/8.1 hosts has been removed, which includes removing support for operating Hyper-V synthetic timers in other than Direct Mode. Update the documentation to reflect these removals. Signed-off-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Naman Jain <namjain@linux.microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
11 daysDrivers: hv: Run VMBus kexec cleanup from syscore shutdownShradha Gupta
ARM64 Hyper-V guests do not run the VMBus kexec cleanup before secondary CPUs are stopped. Consequently, the old VMBus connection and SynIC state remain active when the kexec kernel starts. Run the VMBus kexec handler from the existing VMBus syscore shutdown callback. syscore_shutdown() runs after device shutdown and before machine shutdown, while all CPUs needed by the SynIC CPU hotplug teardown are still available. Guard the callback with kexec_is_in_progress() so normal restart, halt, and poweroff paths are unchanged. Use the same path on x86 and remove the architecture-specific handler pointer and the weak setup/remove interfaces. VMBus teardown now precedes hv_stimer_global_cleanup() on x86. The new x86 ordering relies on commit be0cfab740e5 ("clocksource: hyper-v: Remove support for stimer interrupts in message mode"), which removed the synthetic timer's dependency on VMBus message delivery. Older kernels that retain message-mode stimer interrupts must preserve the existing x86 ordering and therefore require an ARM64-specific backport. Document the VMBus cleanup path and its position in shutdown ordering. Fixes: 9bbb888824e3 ("arm64: hyperv: Initialize hypervisor on boot") Link: https://lore.kernel.org/all/20260814093133.3191250-1-shradhagupta@linux.microsoft.com/ Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Suggested-by: Michael Kelley <mhklinux@outlook.com> Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Bradley Morgan <brads@mainlining.org> Reviewed-by: Naman Jain <namjain@linux.microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
11 daysDocumentation: hyperv: Update documentation for sending VMBus packetsMichael Kelley
The functions for sending VMBus packets have changed. vmbus_sendpacket_mpb_desc() can target multiple ranges, and vmbus_sendpacket_pagebuffer() has been removed. vmbus_sendpacket_getid() has been added. Update the documentation accordingly. Fixes: 45a442fe369e ("Drivers: hv: vmbus: Remove vmbus_sendpacket_pagebuffer()") Cc: stable@vger.kernel.org Signed-off-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Naman Jain <namjain@linux.microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
11 daysDocumentation: hyperv: Describe validation of the ring buffer indicesKameron Carr
Document that the guest must snapshot and validate the read and write indices before using them to index into the ring buffer or to compute the available space. Signed-off-by: Kameron Carr <kameroncarr@linux.microsoft.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
2025-11-15Documentation: hyperv: Confidential VMBusRoman Kisel
Define what the confidential VMBus is and describe what advantages it offers on the capable hardware. Signed-off-by: Roman Kisel <romank@linux.microsoft.com> Reviewed-by: Alok Tiwari <alok.a.tiwari@oracle.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
2025-05-23Documentation: hyperv: Update VMBus doc with new features and infoMichael Kelley
Starting in the 6.15 kernel, VMBus interrupts are automatically assigned away from a CPU that is being taken offline. Add documentation describing this case. Also add details of Hyper-V behavior when the primary channel of a VMBus device is closed as the result of unbinding the device's driver. This behavior has not changed, but it was not previously documented. Signed-off-by: Michael Kelley <mhklinux@outlook.com> Link: https://lore.kernel.org/r/20250520044435.7734-1-mhklinux@outlook.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <20250520044435.7734-1-mhklinux@outlook.com>
2025-01-13Documentation: hyperv: Add overview of guest VM hibernationMichael Kelley
Add documentation on how hibernation works in a guest VM on Hyper-V. Describe how VMBus devices and the VMBus itself are hibernated and resumed, along with various limitations. Signed-off-by: Michael Kelley <mhklinux@outlook.com> Link: https://lore.kernel.org/r/20250113145645.1320942-1-mhklinux@outlook.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <20250113145645.1320942-1-mhklinux@outlook.com>
2024-06-24Documentation: hyperv: Add overview of Confidential Computing VM supportMichael Kelley
Add documentation topic for Confidential Computing (CoCo) VM support in Linux guests on Hyper-V. Signed-off-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Easwar Hariharan <eahariha@linux.microsoft.com> Link: https://lore.kernel.org/r/20240618165059.10174-1-mhklinux@outlook.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <20240618165059.10174-1-mhklinux@outlook.com>
2024-05-28Documentation: hyperv: Improve synic and interrupt handling descriptionMichael Kelley
Current documentation does not describe how Linux handles the synthetic interrupt controller (synic) that Hyper-V provides to guest VMs, nor how VMBus or timer interrupts are handled. Add text describing the synic and reorganize existing text to make this more clear. Signed-off-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Easwar Hariharan <eahariha@linux.microsoft.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Link: https://lore.kernel.org/r/20240511133818.19649-2-mhklinux@outlook.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <20240511133818.19649-2-mhklinux@outlook.com>
2024-05-28Documentation: hyperv: Update spelling and fix typoMichael Kelley
Update spelling from "VMbus" to "VMBus" to match Hyper-V product documentation. Also correct typo: "SNP-SEV" should be "SEV-SNP". Signed-off-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Easwar Hariharan <eahariha@linux.microsoft.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Link: https://lore.kernel.org/r/20240511133818.19649-1-mhklinux@outlook.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <20240511133818.19649-1-mhklinux@outlook.com>
2024-03-01Documentation: hyperv: Add overview of PCI pass-thru device supportMichael Kelley
Add documentation topic for PCI pass-thru devices in Linux guests on Hyper-V and for the associated PCI controller driver (pci-hyperv.c). Signed-off-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Easwar Hariharan <eahariha@linux.microsoft.com> Link: https://lore.kernel.org/r/20240222200710.305259-1-mhklinux@outlook.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <20240222200710.305259-1-mhklinux@outlook.com>
2023-08-18Documentation: Fix typosBjorn Helgaas
Fix typos in Documentation. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20230814212822.193684-4-helgaas@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-13Documentation: hyperv: Add overview of clocks and timersMichael Kelley
Add documentation topic for clocks and timers when running as a guest on Hyper-V. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/1657561704-12631-4-git-send-email-mikelley@microsoft.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-13Documentation: hyperv: Add overview of VMbusMichael Kelley
Add documentation topic for using VMbus when running as a guest on Hyper-V. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/1657561704-12631-3-git-send-email-mikelley@microsoft.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-13Documentation: hyperv: Add overview of Hyper-V enlightenmentsMichael Kelley
Add an initial documentation topic for Linux enlightenments to run as a guest on Microsoft's Hyper-V hypervisor, linked under the "virt" documentation area. Update the virt doc index.rst and the MAINTAINERS file. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/1657561704-12631-2-git-send-email-mikelley@microsoft.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>