kernel/git/stable/linux.git/arch/x86/hyperv, branch master

Merge tag 'hyperv-next-signed-20260826' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

2026-08-26T23:47:40+00:00

Pull hyperv updates from Wei Liu: - Decrypt netvsc buffer on contiguous direct-map addresses (Kameron Carr) - Drop WS2012/2012R2 & Win8/8.1 Hyper-V support (Michael Kelley) - Use more meaningful errnos for hypercall status code (Hardik Garg) - Fix lost interrupts on CPU hot-unplug for Hyper-V PCI/MSI (Naman Jain) - Reserve more MSHV vectors for Linux root partition (Wei Liu) * tag 'hyperv-next-signed-20260826' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: clocksource: hyper-v: Remove support for stimer interrupts in message mode scsi: storvsc: Remove support for storvsc protocol of old Hyper-V hosts hv_netvsc: Remove GPADL teardown special case for old Hyper-V hosts hv_sock: Remove check for old Hyper-V hosts Drivers: hv: Remove support for WS2012/2012R2 & Win8/8.1 version of Hyper-V hv_netvsc: Allocate send/receive buffers using vmbus_alloc_buffer() Drivers: hv: vmbus: Add vmbus_alloc_buffer()/vmbus_free_buffer() for CoCo VMs Drivers: hv: vmbus: add vmbus_establish_gpadl_caller_decrypted() Drivers: hv: vmbus: Skip VMBus module cleanup for non-nested root partition x86/hyperv: reserve more vectors PCI: hv: Set irq_retrigger callback for the Hyper-V PCI MSI irqchip Drivers: hv: Use meaningful errnos for hypercall status codes

clocksource: hyper-v: Remove support for stimer interrupts in message mode

2026-08-24T00:36:14+00:00

In Hyper-V versions prior to WS2016/Win10, Hyper-V synthetic timers interrupt the guest by delivering a message that is initially handled by the Linux VMBus driver. Starting with WS2016/Win10, Hyper-V can deliver stimer interrupts directly to an assigned interrupt vector without involving the VMBus driver. This is called "Direct Mode". With the overall removal of Linux support for running on Hyper-V hosts earlier than WS2016 and Windows 10, it's no longer necessary to support the legacy message-based delivery. Remove that delivery mechanism and always use Direct Mode. If for some reason, the Hyper-V host does not enumerate Direct Mode, output an error message but continue to run using the LAPIC timer instead of an stimer. With these changes, the VMBus driver no longer calls the stimer interrupt service routine. This removal has a broader benefit in unblocking the disentangling of VMBus code and stimer code, as they should be independent of each other. The final disentangling will come as a follow-on patch set. Signed-off-by: Michael Kelley Signed-off-by: Wei Liu

Merge tag 'x86-msr-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2026-08-18T21:02:15+00:00

Pull x86 MSR updates from Ingo Molnar: - Streamline the x86 MSR handling APIs along the 64-bit variants, simplifying the interfaces. Removal of the old APIs is planned for the next cycle, to reduce churn & integration pain (Juergen Gross) * tag 'x86-msr-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) x86/mce: Work around build warning after MSR-interface switch cpufreq: Stop using 32-bit MSR interfaces x86/featctl: Stop using 32-bit MSR interfaces KVM/x86: Stop using 32-bit MSR interfaces x86/mtrr: Stop using 32-bit MSR interfaces acpi: Stop using 32-bit MSR interfaces powercap: Stop using 32-bit MSR interfaces thermal/intel: Stop using 32-bit MSR interfaces x86/olpc: Stop using 32-bit MSR interfaces x86/hyperv: Stop using 32-bit MSR interfaces hwmon: Stop using 32-bit MSR interfaces EDAC: Stop using 32-bit MSR interfaces x86/cpu: Stop using 32-bit MSR interfaces x86/apic: Stop using 32-bit MSR interfaces x86/resctrl: Stop using 32-bit MSR interfaces x86/tsc: Stop using 32-bit MSR interfaces x86/amd: Stop using 32-bit MSR interfaces x86/pci: Stop using 32-bit MSR interfaces x86/hygon: Stop using 32-bit MSR interfaces x86/mce: Stop using 32-bit MSR interfaces ...

x86/paravirt: Use static_call() for the paravirt spinlock ops

2026-08-07T15:58:09+00:00

queued_spin_lock_slowpath() and queued_spin_unlock() are dispatched through pv_ops_lock via the paravirt-ops ALTERNATIVE machinery, which picks the target (native inline store / hypervisor call) once at boot and cannot change at runtime. Convert both to static_call(). The site becomes a direct call patched in place (one byte smaller), and on native the unlock still collapses to the inline "movb $0, (%rdi)" store, so the fast path is unchanged. Unlike the ALTERNATIVE mechanism, a static_call() target can also be updated at runtime via static_call_update(). This is a prerequisite for the contended_release tracepoint, which has to swap in a traced unlock while the system is running. [ ilvokhin: commit message; fix PARAVIRT_SPINLOCKS=n build; teach __static_call_validate() about the inline unlock insn; make the slowpath site module-safe: static_call_mod() + EXPORT_STATIC_CALL_TRAMP(); pass @lock to the callee-save unlock, fixing a boot hang under CALL_DEPTH_TRACKING. Boot tested native + KVM PV guest. ] Signed-off-by: Peter Zijlstra (Intel) Co-developed-by: Dmitry Ilvokhin Signed-off-by: Dmitry Ilvokhin Signed-off-by: Peter Zijlstra (Intel) Acked-by: Juergen Gross Link: https://lore.kernel.org/all/20260603120811.GW3493090@noisy.programming.kicks-ass.net/ Link: https://patch.msgid.link/9a32ae399eb804a02a31af04dcabe7e7ee4f3fdf.1785778551.git.d@ilvokhin.com

x86/hyperv: Stop using 32-bit MSR interfaces

2026-07-03T09:33:59+00:00

The 32-bit MSR interface rdmsr() is planned to be removed. Use the related 64-bit variant instead. This conversion also simplifies the code a bit. Signed-off-by: Juergen Gross Signed-off-by: Ingo Molnar Cc: K. Y. Srinivasan Cc: Dexuan Cui Cc: Haiyang Zhang Cc: Long Li Cc: Wei Liu Link: https://patch.msgid.link/20260629060526.3638272-28-jgross@suse.com

Merge tag 'hyperv-next-signed-20260621' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

2026-06-22T15:06:13+00:00

Pull hyperv updates from Wei Liu: - Use wakeup mailbox to boot APs in Hyper-V VTL2 TDX guests (Yunhong Jiang, Ricardo Neri) - Move the Hyper-V IOMMU to its own subdirectory (Mukesh Rathor) - Cosmetic changes to mshv and balloon driver (Junrui Luo, Markus Elfring) * tag 'hyperv-next-signed-20260621' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: mshv: add bounds check on vp_index in mshv_intercept_isr() hv_balloon: Simplify data output in hv_balloon_debug_show() x86/hyperv: Cosmetic changes in irqdomain.c for readability iommu/hyperv: Create hyperv subdirectory under drivers/iommu x86/hyperv/vtl: Use the wakeup mailbox to boot secondary CPUs x86/hyperv/vtl: Mark the wakeup mailbox page as private x86/acpi: Add a helper to get the address of the wakeup mailbox x86/hyperv/vtl: Setup the 64-bit trampoline for TDX guests x86/realmode: Make the location of the trampoline configurable x86/hyperv/vtl: Set real_mode_header in hv_vtl_init_platform() x86/dt: Parse the Wakeup Mailbox for Intel processors dt-bindings: reserved-memory: Wakeup Mailbox for Intel processors x86/acpi: Add functions to setup and access the wakeup mailbox x86/topology: Add missing struct declaration and attribute dependency

x86/hyperv: Cosmetic changes in irqdomain.c for readability

2026-06-08T05:59:49+00:00

Make cosmetic changes: o Rename struct pci_dev *dev to *pdev since there are cases of struct device *dev in the file and all over the kernel o Rename hv_build_pci_dev_id to hv_build_devid_type_pci in anticipation of building different types of device ids o Fix checkpatch.pl issues with return and extraneous printk o Replace spaces with tabs o Rename struct hv_devid *xxx to struct hv_devid *hv_devid given code paths involve many types of device ids o Fix indentation in a large if block by using goto. There are no functional changes. Reviewed-by: Souradeep Chakrabarti Reviewed-by: Anirudh Rayabharam (Microsoft) Signed-off-by: Mukesh R Signed-off-by: Wei Liu

x86/hyperv/vtl: Use the wakeup mailbox to boot secondary CPUs

2026-05-28T20:01:26+00:00

The hypervisor is an untrusted entity for TDX guests. It cannot be used to boot secondary CPUs. The function hv_vtl_wakeup_secondary_cpu() cannot be used. Instead, the virtual firmware boots the secondary CPUs and places them in a state to transfer control to the kernel using the wakeup mailbox. The firmware enumerates the mailbox via either an ACPI table or a DeviceTree node. If the wakeup mailbox is present, the kernel updates the APIC callback wakeup_secondary_cpu_64() to use it. Reviewed-by: Dexuan Cui Reviewed-by: Michael Kelley Signed-off-by: Ricardo Neri Signed-off-by: Dexuan Cui

x86/hyperv/vtl: Mark the wakeup mailbox page as private

2026-05-28T20:01:26+00:00

The current code maps MMIO devices as shared (decrypted) by default in a confidential computing VM. In a TDX environment, secondary CPUs are booted using the Multiprocessor Wakeup Structure defined in the ACPI specification. The virtual firmware and the operating system function in the guest context, without intervention from the VMM. Map the physical memory of the mailbox as private. Use the is_private_mmio() callback. Signed-off-by: Yunhong Jiang Signed-off-by: Ricardo Neri Signed-off-by: Dexuan Cui

x86/hyperv/vtl: Setup the 64-bit trampoline for TDX guests

2026-05-28T20:01:25+00:00

The hypervisor is an untrusted entity for TDX guests. It cannot be used to boot secondary CPUs - neither via hypercalls nor the INIT assert, de-assert, plus Start-Up IPI messages. Instead, the platform virtual firmware boots the secondary CPUs and puts them in a state to transfer control to the kernel. This mechanism uses the wakeup mailbox described in the Multiprocessor Wakeup Structure of the ACPI specification. The entry point to the kernel is trampoline_start64. Allocate and setup the trampoline using the default x86_platform callbacks. The platform firmware configures the secondary CPUs in long mode. It is no longer necessary to locate the trampoline under 1MB memory. After handoff from firmware, the trampoline code switches briefly to 32-bit addressing mode, which has an addressing limit of 4GB. Set the upper bound of the trampoline memory accordingly. Reviewed-by: Dexuan Cui Reviewed-by: Michael Kelley Signed-off-by: Yunhong Jiang Signed-off-by: Ricardo Neri Signed-off-by: Dexuan Cui