kernel/arch/x86/include/asm/hyperv-tlfs.h, branch linux-5.14.y

hyperv: SVM enlightened TLB flush support flag

2021-06-17T17:09:36Z

Bit 22 of HYPERV_CPUID_FEATURES.EDX is specific to SVM and specifies support for enlightened TLB flush. With this enlightenment enabled, ASID invalidations flushes only gva->hpa entries. To flush TLB entries derived from NPT, hypercalls should be used (HvFlushGuestPhysicalAddressSpace or HvFlushGuestPhysicalAddressList) Signed-off-by: Vineeth Pillai Reviewed-by: Michael Kelley Message-Id: Signed-off-by: Paolo Bonzini

KVM: hyper-v: Advertise support for fast XMM hypercalls

2021-06-17T17:09:24Z

Now that kvm_hv_flush_tlb() has been patched to support XMM hypercall inputs, we can start advertising this feature to guests. Cc: Alexander Graf Cc: Evgeny Iakovlev Signed-off-by: Siddharth Chandrasekaran Message-Id: Signed-off-by: Paolo Bonzini

KVM: x86: kvm_hv_flush_tlb use inputs from XMM registers

2021-06-17T17:09:24Z

Hyper-V supports the use of XMM registers to perform fast hypercalls. This allows guests to take advantage of the improved performance of the fast hypercall interface even though a hypercall may require more than (the current maximum of) two input registers. The XMM fast hypercall interface uses six additional XMM registers (XMM0 to XMM5) to allow the guest to pass an input parameter block of up to 112 bytes. Add framework to read from XMM registers in kvm_hv_hypercall() and use the additional hypercall inputs from XMM registers in kvm_hv_flush_tlb() when possible. Cc: Alexander Graf Co-developed-by: Evgeny Iakovlev Signed-off-by: Evgeny Iakovlev Signed-off-by: Siddharth Chandrasekaran Message-Id: Signed-off-by: Paolo Bonzini

Drivers: hv: Redo Hyper-V synthetic MSR get/set functions

2021-03-08T17:32:59Z

Current code defines a separate get and set macro for each Hyper-V synthetic MSR used by the VMbus driver. Furthermore, the get macro can't be converted to a standard function because the second argument is modified in place, which is somewhat bad form. Redo this by providing a single get and a single set function that take a parameter specifying the MSR to be operated on. Fixup usage of the get function. Calling locations are no more complex than before, but the code under arch/x86 and the upcoming code under arch/arm64 is significantly simplified. Also standardize the names of Hyper-V synthetic MSRs that are architecture neutral. But keep the old x86-specific names as aliases that can be removed later when all references (particularly in KVM code) have been cleaned up in a separate patch series. No functional change. Signed-off-by: Michael Kelley Reviewed-by: Boqun Feng Link: https://lore.kernel.org/r/1614721102-2241-4-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu

x86/hyper-v: Move hv_message_type to architecture neutral module

2021-03-08T17:32:59Z

The definition of enum hv_message_type includes arch neutral and x86/x64-specific values. Ideally there would be a way to put the arch neutral values in an arch neutral module, and the arch specific values in an arch specific module. But C doesn't provide a way to extend enum types. As a compromise, move the entire definition into an arch neutral module, to avoid duplicating the arch neutral values for x86/x64 and for ARM64. No functional change. Signed-off-by: Michael Kelley Reviewed-by: Boqun Feng Link: https://lore.kernel.org/r/1614721102-2241-3-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu

asm-generic/hyperv: import data structures for mapping device interrupts

2021-02-11T08:47:06Z

Signed-off-by: Sunil Muthuswamy Co-Developed-by: Sunil Muthuswamy Signed-off-by: Wei Liu Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20210203150435.27941-15-wei.liu@kernel.org

x86/hyperv: detect if Linux is the root partition

2021-02-11T08:47:05Z

For now we can use the privilege flag to check. Stash the value to be used later. Put in a bunch of defines for future use when we want to have more fine-grained detection. Signed-off-by: Wei Liu Reviewed-by: Pavel Tatashin Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20210203150435.27941-3-wei.liu@kernel.org

x86/hyperv: Load/save the Isolation Configuration leaf

2021-02-11T08:47:05Z

If bit 22 of Group B Features is set, the guest has access to the Isolation Configuration CPUID leaf. On x86, the first four bits of EAX in this leaf provide the isolation type of the partition; we entail three isolation types: 'SNP' (hardware-based isolation), 'VBS' (software-based isolation), and 'NONE' (no isolation). Signed-off-by: Andrea Parri (Microsoft) Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: "H. Peter Anvin" Cc: Arnd Bergmann Cc: x86@kernel.org Cc: linux-arch@vger.kernel.org Link: https://lore.kernel.org/r/20210201144814.2701-2-parri.andrea@gmail.com Reviewed-by: Michael Kelley Signed-off-by: Wei Liu

x86/hyperv: Enable 15-bit APIC ID if the hypervisor supports it

2020-11-04T10:10:52Z

When a Linux VM runs on Hyper-V, if the VM has CPUs with >255 APIC IDs, the CPUs can't be the destination of IOAPIC interrupts, because the IOAPIC RTE's Dest Field has only 8 bits. Currently the hackery driver drivers/iommu/hyperv-iommu.c is used to ensure IOAPIC interrupts are only routed to CPUs that don't have >255 APIC IDs. However, there is an issue with kdump, because the kdump kernel can run on any CPU, and hence IOAPIC interrupts can't work if the kdump kernel run on a CPU with a >255 APIC ID. The kdump issue can be fixed by the Extended Dest ID, which is introduced recently by David Woodhouse (for IOAPIC, see the field virt_destid_8_14 in struct IO_APIC_route_entry). Of course, the Extended Dest ID needs the support of the underlying hypervisor. The latest Hyper-V has added the support recently: with this commit, on such a Hyper-V host, Linux VM does not use hyperv-iommu.c because hyperv_prepare_irq_remapping() returns -ENODEV; instead, Linux kernel's generic support of Extended Dest ID from David is used, meaning that Linux VM is able to support up to 32K CPUs, and IOAPIC interrupts can be routed to all the CPUs. On an old Hyper-V host that doesn't support the Extended Dest ID, nothing changes with this commit: Linux VM is still able to bring up the CPUs with > 255 APIC IDs with the help of hyperv-iommu.c, but IOAPIC interrupts still can not go to such CPUs, and the kdump kernel still can not work properly on such CPUs. [ tglx: Updated comment as suggested by David ] Signed-off-by: Dexuan Cui Signed-off-by: Thomas Gleixner Acked-by: David Woodhouse Link: https://lore.kernel.org/r/20201103011136.59108-1-decui@microsoft.com

x86/hyperv: Remove aliases with X64 in their name

2020-09-27T09:34:54Z

In the architecture independent version of hyperv-tlfs.h, commit c55a844f46f958b removed the "X64" in the symbol names so they would make sense for both x86 and ARM64. That commit added aliases with the "X64" in the x86 version of hyperv-tlfs.h so that existing x86 code would continue to compile. As a cleanup, update the x86 code to use the symbols without the "X64", then remove the aliases. There's no functional change. Signed-off-by: Joseph Salisbury Signed-off-by: Thomas Gleixner Reviewed-by: Michael Kelley Acked-by: Paolo Bonzini Link: https://lore.kernel.org/r/1601130386-11111-1-git-send-email-jsalisbury@linux.microsoft.com