Changes in Kconfig

621191d7 - Drivers: hv: Introduce mshv_root module to expose /dev/mshv to VMMs

Fri, 14 Mar 2025 19:28:56 +0000

Drivers: hv: Introduce mshv_root module to expose /dev/mshv to VMMsProvide a set of IOCTLs for creating and managing child partitions whenrunning as root partition on Hyper-V. The new driver is enabled viaCONFIG_MSHV_ROOT.A brief overview of the interface:MSHV_CREATE_PARTITION is the entry point, returning a file descriptorrepresenting a child partition. IOCTLs on this fd can be used to mapmemory, create VPs, etc.Creating a VP returns another file descriptor representing that VP whichin turn has another set of corresponding IOCTLs for running the VP,getting/setting state, etc.MSHV_ROOT_HVCALL is a generic "passthrough" hypercall IOCTL which can beused for a number of partition or VP hypercalls. This is for hypercallsthat do not affect any state in the kernel driver, such as getting andsetting VP registers and partition properties, translating addresses,etc. It is "passthrough" because the binary input and output for thehypercall is only interpreted by the VMM - the kernel driver doesnothing but insert the VP and partition id where necessary (which arealways in the same place), and execute the hypercall.Co-developed-by: Anirudh Rayabharam Signed-off-by: Anirudh Rayabharam Co-developed-by: Jinank Jain Signed-off-by: Jinank Jain Co-developed-by: Mukesh Rathor Signed-off-by: Mukesh Rathor Co-developed-by: Muminul Islam Signed-off-by: Muminul Islam Co-developed-by: Praveen K Paladugu Signed-off-by: Praveen K Paladugu Co-developed-by: Stanislav Kinsburskii Signed-off-by: Stanislav Kinsburskii Co-developed-by: Wei Liu Signed-off-by: Nuno Das Neves Reviewed-by: Roman Kisel Link: https://lore.kernel.org/r/1741980536-3865-11-git-send-email-nunodasneves@linux.microsoft.comSigned-off-by: Wei Liu Message-ID: <1741980536-3865-11-git-send-email-nunodasneves@linux.microsoft.com> List of files: /linux-6.15/drivers/hv/Kconfig

461fbbd0 - hyperv: Add CONFIG_MSHV_ROOT to gate root partition support

Fri, 21 Feb 2025 19:56:35 +0000

hyperv: Add CONFIG_MSHV_ROOT to gate root partition supportCONFIG_MSHV_ROOT allows kernels built to run as a normal Hyper-V guestto exclude the root partition code, which is expected to growsignificantly over time.This option is a tristate so future driver code can be built as a(m)odule, allowing faster development iteration cycles.If CONFIG_MSHV_ROOT is disabled, don't compile hv_proc.c, and stubhv_root_partition() to return false unconditionally. This allows thecompiler to optimize away root partition code blocks since they willbe disabled at compile time.In the case of booting as root partition *without* CONFIG_MSHV_ROOTenabled, print a critical error (the kernel will likely crash).Signed-off-by: Nuno Das Neves Reviewed-by: Easwar Hariharan Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/1740167795-13296-4-git-send-email-nunodasneves@linux.microsoft.comSigned-off-by: Wei Liu Message-ID: <1740167795-13296-4-git-send-email-nunodasneves@linux.microsoft.com> List of files: /linux-6.15/drivers/hv/Kconfig

2b4b90e0 - x86/hyperv: Use per cpu initial stack for vtl context

Sun, 03 Mar 2024 08:01:36 +0000

x86/hyperv: Use per cpu initial stack for vtl contextCurrently, the secondary CPUs in Hyper-V VTL context lack support forparallel startup. Therefore, relying on the single initial_stack fetchedfrom the current task structure suffices for all vCPUs.However, common initial_stack risks stack corruption when parallel startupis enabled. In order to facilitate parallel startup, use the initial_stackfrom the per CPU idle thread instead of the current task.Fixes: 3be1bc2fe9d2 ("x86/hyperv: VTL support for Hyper-V")Signed-off-by: Saurabh Sengar Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/1709452896-13342-1-git-send-email-ssengar@linux.microsoft.comSigned-off-by: Wei Liu Message-ID: <1709452896-13342-1-git-send-email-ssengar@linux.microsoft.com> List of files: /linux-6.15/drivers/hv/Kconfig

d01b9a9f - Drivers: hv: Kconfig: Add HYPERV_VTL_MODE

Tue, 11 Apr 2023 05:55:31 +0000

Drivers: hv: Kconfig: Add HYPERV_VTL_MODEAdd HYPERV_VTL_MODE Kconfig flag for VTL mode.Signed-off-by: Saurabh Sengar Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/1681192532-15460-5-git-send-email-ssengar@linux.microsoft.comSigned-off-by: Wei Liu List of files: /linux-6.15/drivers/hv/Kconfig

25727aae - hv_netvsc: Remove second mapping of send and recv buffers

Sun, 26 Mar 2023 13:52:05 +0000

hv_netvsc: Remove second mapping of send and recv buffersWith changes to how Hyper-V guest VMs flip memory between private(encrypted) and shared (decrypted), creating a second kernel virtualmapping for shared memory is no longer necessary. Everything neededfor the transition to shared is handled by set_memory_decrypted().As such, remove the code to create and manage the secondmapping for the pre-allocated send and recv buffers. This mappingis the last user of hv_map_memory()/hv_unmap_memory(), so deletethese functions as well. Finally, hv_map_memory() is the lastuser of vmap_pfn() in Hyper-V guest code, so remove the Kconfigselection of VMAP_PFN.Signed-off-by: Michael Kelley Reviewed-by: Tianyu Lan Link: https://lore.kernel.org/r/1679838727-87310-11-git-send-email-mikelley@microsoft.comSigned-off-by: Wei Liu List of files: /linux-6.15/drivers/hv/Kconfig

f83705a5 - Driver: VMBus: Add Devicetree support

Mon, 20 Mar 2023 07:47:40 +0000

Driver: VMBus: Add Devicetree supportUpdate the driver to support Devicetree boot as well along with ACPI.At present the Devicetree parsing only provides the mmio region infoand is not the exact copy of ACPI parsing. This is sufficient to caterall the current Devicetree usecases for VMBus.Currently Devicetree is supported only for x86 systems.Signed-off-by: Saurabh Sengar Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/1679298460-11855-6-git-send-email-ssengar@linux.microsoft.comSigned-off-by: Wei Liu List of files: /linux-6.15/drivers/hv/Kconfig

1dc2f2b8 - hv: utils: add PTP_1588_CLOCK to Kconfig to fix build

Fri, 26 Nov 2021 02:33:16 +0000

hv: utils: add PTP_1588_CLOCK to Kconfig to fix buildThe hyperv utilities use PTP clock interfaces and should depend aa kconfig symbol such that they will be built as a loadable module orbuiltin so that linker errors do not happen.Prevents these build errors:ld: drivers/hv/hv_util.o: in function `hv_timesync_deinit':hv_util.c:(.text+0x37d): undefined reference to `ptp_clock_unregister'ld: drivers/hv/hv_util.o: in function `hv_timesync_init':hv_util.c:(.text+0x738): undefined reference to `ptp_clock_register'Fixes: 3716a49a81ba ("hv_utils: implement Hyper-V PTP source")Signed-off-by: Randy Dunlap Reported-by: kernel test robot Cc: Arnd Bergmann Cc: "K. Y. Srinivasan" Cc: Haiyang Zhang Cc: Stephen Hemminger Cc: Wei Liu Cc: Dexuan Cui Cc: linux-hyperv@vger.kernel.orgCc: Greg Kroah-Hartman Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20211126023316.25184-1-rdunlap@infradead.orgSigned-off-by: Wei Liu List of files: /linux-6.15/drivers/hv/Kconfig

9a879772 - Drivers: hv: vmbus: Initialize VMbus ring buffer for Isolation VM

Mon, 25 Oct 2021 12:21:14 +0000

Drivers: hv: vmbus: Initialize VMbus ring buffer for Isolation VMVMbus ring buffer are shared with host and it's need tobe accessed via extra address space of Isolation VM withAMD SNP support. This patch is to map the ring bufferaddress in extra address space via vmap_pfn(). Hyperv setmemory host visibility hvcall smears data in the ring bufferand so reset the ring buffer memory to zero after mapping.Reviewed-by: Michael Kelley Signed-off-by: Tianyu Lan Link: https://lore.kernel.org/r/20211025122116.264793-10-ltykernel@gmail.comSigned-off-by: Wei Liu List of files: /linux-6.15/drivers/hv/Kconfig

7aff79e2 - Drivers: hv: Enable Hyper-V code to be built on ARM64

Wed, 04 Aug 2021 15:52:39 +0000

Drivers: hv: Enable Hyper-V code to be built on ARM64Update drivers/hv/Kconfig so CONFIG_HYPERV can be selected onARM64, causing the Hyper-V specific code to be built. Exclude theHyper-V enlightened clocks/timers code from being built for ARM64.Signed-off-by: Michael Kelley Reviewed-by: Boqun Feng Acked-by: Marc Zyngier Acked-by: Mark Rutland Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/1628092359-61351-6-git-send-email-mikelley@microsoft.comSigned-off-by: Wei Liu List of files: /linux-6.15/drivers/hv/Kconfig

6dc2a774 - x86/Hyper-V: Support for free page reporting

Tue, 23 Mar 2021 18:47:16 +0000

x86/Hyper-V: Support for free page reportingLinux has support for free page reporting now (36e66c554b5c) forvirtualized environment. On Hyper-V when virtually backed VMs areconfigured, Hyper-V will advertise cold memory discard capability,when supported. This patch adds the support to hook into the freepage reporting infrastructure and leverage the Hyper-V cold memorydiscard hint hypercall to report/free these pages back to the host.Signed-off-by: Sunil Muthuswamy Tested-by: Matheus Castello Reviewed-by: Michael Kelley Tested-by: Nathan Chancellor Link: https://lore.kernel.org/r/SN4PR2101MB0880121FA4E2FEC67F35C1DCC0649@SN4PR2101MB0880.namprd21.prod.outlook.comSigned-off-by: Wei Liu List of files: /linux-6.15/drivers/hv/Kconfig

3e2d9453 - clocksource/drivers/hyperv: Enable TSC page clocksource on 32bit

Thu, 22 Aug 2019 08:36:30 +0000

clocksource/drivers/hyperv: Enable TSC page clocksource on 32bitThere is no particular reason to not enable TSC page clocksource on32-bit. mul_u64_u64_shr() is available and despite the increasedcomputational complexity (compared to 64bit) TSC page is still a huge wincompared to MSR-based clocksource.In-kernel reads: MSR based clocksource: 3361 cycles TSC page clocksource: 49 cyclesReads from userspace (utilizing vDSO in case of TSC page): MSR based clocksource: 5664 cycles TSC page clocksource: 131 cyclesEnabling TSC page on 32bits allows to get rid of CONFIG_HYPERV_TSCPAGE asit is now not any different from CONFIG_HYPERV_TIMER.Signed-off-by: Vitaly Kuznetsov Signed-off-by: Thomas Gleixner Reviewed-by: Michael Kelley Link: https://lkml.kernel.org/r/20190822083630.17059-1-vkuznets@redhat.com List of files: /linux-6.15/drivers/hv/Kconfig

fd1fea68 - clocksource/drivers: Make Hyper-V clocksource ISA agnostic

Mon, 01 Jul 2019 04:25:56 +0000

clocksource/drivers: Make Hyper-V clocksource ISA agnosticHyper-V clock/timer code and data structures are currently mixedin with other code in the ISA independent drivers/hv directory aswell as the ISA dependent Hyper-V code under arch/x86.Consolidate this code and data structures into a Hyper-V clocksource driverto better follow the Linux model. In doing so, separate out the ISAdependent portions so the new clocksource driver works for x86 and for thein-process Hyper-V on ARM64 code.To start, move the existing clockevents code to create the new clocksourcedriver. Update the VMbus driver to call initialization and cleanup routinessince the Hyper-V synthetic timers are not independently enumerated inACPI.No behavior is changed and no new functionality is added.Suggested-by: Marc Zyngier Signed-off-by: Michael Kelley Signed-off-by: Thomas Gleixner Reviewed-by: Vitaly Kuznetsov Cc: "bp@alien8.de" Cc: "will.deacon@arm.com" Cc: "catalin.marinas@arm.com" Cc: "mark.rutland@arm.com" Cc: "linux-arm-kernel@lists.infradead.org" Cc: "gregkh@linuxfoundation.org" Cc: "linux-hyperv@vger.kernel.org" Cc: "olaf@aepfle.de" Cc: "apw@canonical.com" Cc: "jasowang@redhat.com" Cc: "marcelo.cerri@canonical.com" Cc: Sunil Muthuswamy Cc: KY Srinivasan Cc: "sashal@kernel.org" Cc: "vincenzo.frascino@arm.com" Cc: "linux-arch@vger.kernel.org" Cc: "linux-mips@vger.kernel.org" Cc: "linux-kselftest@vger.kernel.org" Cc: "arnd@arndb.de" Cc: "linux@armlinux.org.uk" Cc: "ralf@linux-mips.org" Cc: "paul.burton@mips.com" Cc: "daniel.lezcano@linaro.org" Cc: "salyzyn@android.com" Cc: "pcc@google.com" Cc: "shuah@kernel.org" Cc: "0x7f454c46@gmail.com" <0x7f454c46@gmail.com>Cc: "linux@rasmusvillemoes.dk" Cc: "huw@codeweavers.com" Cc: "sfr@canb.auug.org.au" Cc: "pbonzini@redhat.com" Cc: "rkrcmar@redhat.com" Cc: "kvm@vger.kernel.org" Link: https://lkml.kernel.org/r/1561955054-1838-2-git-send-email-mikelley@microsoft.com List of files: /linux-6.15/drivers/hv/Kconfig

ecca2502 - x86/Kconfig: Add new X86_HV_CALLBACK_VECTOR config symbol

Tue, 30 Apr 2019 03:45:23 +0000

x86/Kconfig: Add new X86_HV_CALLBACK_VECTOR config symbolAdd a special Kconfig symbol X86_HV_CALLBACK_VECTOR so that the guestsusing the hypervisor interrupt callback counter can select and thusenable that counter. Select it when xen or hyperv support is enabled. Nofunctional changes.Signed-off-by: Zhao Yakui Signed-off-by: Borislav Petkov Reviewed-by: Borislav Petkov Reviewed-by: Thomas Gleixner Cc: Boris Ostrovsky Cc: Frederic Weisbecker Cc: Haiyang Zhang Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Juergen Gross Cc: "K. Y. Srinivasan" Cc: linux-hyperv@vger.kernel.orgCc: Nicolai Stange Cc: Paolo Bonzini Cc: Peter Zijlstra Cc: Sasha Levin Cc: Stefano Stabellini Cc: Stephen Hemminger Cc: Thomas Gleixner Cc: x86-ml Cc: xen-devel@lists.xenproject.orgLink: https://lkml.kernel.org/r/1559108037-18813-2-git-send-email-yakui.zhao@intel.com List of files: /linux-6.15/drivers/hv/Kconfig

c629421a - x86, hyperv: remove PCI dependency

Sat, 01 Dec 2018 21:40:38 +0000

x86, hyperv: remove PCI dependencyNeed to be able to boot without PCI devices present.Signed-off-by: Sinan Kaya Signed-off-by: Sasha Levin List of files: /linux-6.15/drivers/hv/Kconfig

45ea83f0 - hv: add SPDX license id to Kconfig

Tue, 27 Mar 2018 22:01:04 +0000

hv: add SPDX license id to KconfigMissing license on Kconfig file.Signed-off-by: Stephen Hemminger Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman List of files: /linux-6.15/drivers/hv/Kconfig

2ffd9e33 - x86/hyper-v: Use hypercall for remote TLB flush

Wed, 02 Aug 2017 16:09:19 +0000

x86/hyper-v: Use hypercall for remote TLB flushHyper-V host can suggest us to use hypercall for doing remote TLB flush,this is supposed to work faster than IPIs.Implementation details: to do HvFlushVirtualAddress{Space,List} hypercallswe need to put the input somewhere in memory and we don't really want tohave memory allocation on each call so we pre-allocate per cpu memory areason boot.pv_ops patching is happening very early so we need to separatehyperv_setup_mmu_ops() and hyper_alloc_mmu().It is possible and easy to implement local TLB flushing too and there iseven a hint for that. However, I don't see a room for optimization on thehost side as both hypercall and native tlb flush will result in vmexit. Thehint is also not set on modern Hyper-V versions.Signed-off-by: Vitaly Kuznetsov Reviewed-by: Andy Shevchenko Reviewed-by: Stephen Hemminger Cc: Andy Lutomirski Cc: Haiyang Zhang Cc: Jork Loeser Cc: K. Y. Srinivasan Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Simon Xiao Cc: Steven Rostedt Cc: Thomas Gleixner Cc: devel@linuxdriverproject.orgLink: http://lkml.kernel.org/r/20170802160921.21791-8-vkuznets@redhat.comSigned-off-by: Ingo Molnar List of files: /linux-6.15/drivers/hv/Kconfig

bd2a9ada - x86/hyperv: Implement hv_get_tsc_page()

Fri, 03 Mar 2017 13:21:40 +0000

x86/hyperv: Implement hv_get_tsc_page()To use Hyper-V TSC page clocksource from vDSO we need to make tsc_pgavailable. Implement hv_get_tsc_page() and add CONFIG_HYPERV_TSCPAGE tomake #ifdef-s simple.Signed-off-by: Vitaly Kuznetsov Cc: Stephen Hemminger Cc: Haiyang Zhang Cc: Dexuan Cui Cc: Andy Lutomirski Cc: devel@linuxdriverproject.orgCc: "K. Y. Srinivasan" Cc: virtualization@lists.linux-foundation.orgLink: http://lkml.kernel.org/r/20170303132142.25595-2-vkuznets@redhat.comSigned-off-by: Thomas Gleixner List of files: /linux-6.15/drivers/hv/Kconfig

6276a074 - x86: Make Linux guest support optional

Mon, 04 Mar 2013 20:20:21 +0000

x86: Make Linux guest support optionalPut all config options needed to run Linux as a guest behind aCONFIG_HYPERVISOR_GUEST menu so that they don't get built-in by defaultbut be selectable by the user. Also, make all units which depend onx86_hyper, depend on this new symbol so that compilation doesn't failwhen CONFIG_HYPERVISOR_GUEST is disabled but those units assume itspresence.Sort options in the new HYPERVISOR_GUEST menu, adapt config text anddrop redundant select.Signed-off-by: Borislav Petkov Link: http://lkml.kernel.org/r/1362428421-9244-3-git-send-email-bp@alien8.deCc: Dmitry Torokhov Cc: K. Y. Srinivasan Cc: Haiyang Zhang Signed-off-by: H. Peter Anvin List of files: /linux-6.15/drivers/hv/Kconfig

cb20e5f2 - x86, hyperv: HYPERV depends on X86_LOCAL_APIC

Wed, 13 Feb 2013 01:46:23 +0000

x86, hyperv: HYPERV depends on X86_LOCAL_APICIn order to compile in the special Hyper-V interrupt vector, we needinfrastructure in arch/x86/apic/apic.c. At least for now, simplyrequire CONFIG_X86_LOCAL_APIC in order to enable CONFIG_HYPERV.Link: http://lkml.kernel.org/r/tip-bc2b0331e077f576369a2b6c75d15ed4de4ef91f@git.kernel.orgCc: K. Y. Srinivasan Signed-off-by: H. Peter Anvin List of files: /linux-6.15/drivers/hv/Kconfig

9aa8b50b - Drivers: hv: Add Hyper-V balloon driver

Wed, 14 Nov 2012 09:09:02 +0000

Drivers: hv: Add Hyper-V balloon driverAdd the basic balloon driver. Windows hosts dynamically manage the guestmemory allocation via a combination memory hot add and ballooning. Memoryhot add is used to grow the guest memory upto the maximum memory that can beallocatted to the guest. Ballooning is used to both shrink as well as expandup to the max memory. Supporting hot add needs additional support from thehost. We will support hot add when this support is available. For now,by setting the VM startup memory to the VM max memory, we can useballooning alone to dynamically manage memory allocation amongstcompeting guests on a given host.Signed-off-by: K. Y. Srinivasan Reviewed-by: Haiyang Zhang Signed-off-by: Greg Kroah-Hartman List of files: /linux-6.15/drivers/hv/Kconfig