kernel.git/arch/x86/kernel/cpu/mshyperv.c, branch linux-4.19.y

x86/hyperv: Set X86_FEATURE_TSC_KNOWN_FREQ when Hyper-V provides frequency

2024-11-08T15:19:03Z

[ Upstream commit 8fcc514809de41153b43ccbe1a0cdf7f72b78e7e ] A Linux guest on Hyper-V gets the TSC frequency from a synthetic MSR, if available. In this case, set X86_FEATURE_TSC_KNOWN_FREQ so that Linux doesn't unnecessarily do refined TSC calibration when setting up the TSC clocksource. With this change, a message such as this is no longer output during boot when the TSC is used as the clocksource: [ 1.115141] tsc: Refined TSC clocksource calibration: 2918.408 MHz Furthermore, the guest and host will have exactly the same view of the TSC frequency, which is important for features such as the TSC deadline timer that are emulated by the Hyper-V host. Signed-off-by: Michael Kelley Reviewed-by: Roman Kisel Link: https://lore.kernel.org/r/20240606025559.1631-1-mhklinux@outlook.com Signed-off-by: Wei Liu Message-ID: <20240606025559.1631-1-mhklinux@outlook.com> Signed-off-by: Sasha Levin

x86: hyperv: report value of misc_features

2020-05-02T15:25:55Z

[ Upstream commit 97d9f1c43bedd400301d6f1eff54d46e8c636e47 ] A few kernel features depend on ms_hyperv.misc_features, but unlike its siblings ->features and ->hints, the value was never reported during boot. Signed-off-by: Olaf Hering Link: https://lore.kernel.org/r/20200407172739.31371-1-olaf@aepfle.de Signed-off-by: Wei Liu Signed-off-by: Sasha Levin

x86/Hyper-V: Report crash register data or kmsg before running crash kernel

2020-04-23T08:30:14Z

commit a11589563e96bf262767294b89b25a9d44e7303b upstream. We want to notify Hyper-V when a Linux guest VM crash occurs, so there is a record of the crash even when kdump is enabled. But crash_kexec_post_notifiers defaults to "false", so the kdump kernel runs before the notifiers and Hyper-V never gets notified. Fix this by always setting crash_kexec_post_notifiers to be true for Hyper-V VMs. Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic") Reviewed-by: Michael Kelley Signed-off-by: Tianyu Lan Link: https://lore.kernel.org/r/20200406155331.2105-5-Tianyu.Lan@microsoft.com Signed-off-by: Wei Liu Signed-off-by: Greg Kroah-Hartman

x86/hyper-v: Enable PIT shutdown quirk

2018-11-21T08:19:20Z

commit 1de72c706488b7be664a601cf3843bd01e327e58 upstream. Hyper-V emulation of the PIT has a quirk such that the normal PIT shutdown path doesn't work, because clearing the counter register restarts the timer. Disable the counter clearing on PIT shutdown. Signed-off-by: Michael Kelley Signed-off-by: Thomas Gleixner Cc: "gregkh@linuxfoundation.org" Cc: "devel@linuxdriverproject.org" Cc: "daniel.lezcano@linaro.org" Cc: "virtualization@lists.linux-foundation.org" Cc: "jgross@suse.com" Cc: "akataria@vmware.com" Cc: "olaf@aepfle.de" Cc: "apw@canonical.com" Cc: vkuznets Cc: "jasowang@redhat.com" Cc: "marcelo.cerri@canonical.com" Cc: KY Srinivasan Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1541303219-11142-3-git-send-email-mikelley@microsoft.com Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: Make TLFS #define names architecture neutral

2018-07-03T11:09:15Z

The Hyper-V feature and hint flags in hyperv-tlfs.h are all defined with the string "X64" in the name. Some of these flags are indeed x86/x64 specific, but others are not. For the ones that are used in architecture independent Hyper-V driver code, or will be used in the upcoming support for Hyper-V for ARM64, this patch removes the "X64" from the name. This patch changes the flags that are currently known to be used on multiple architectures. Hyper-V for ARM64 is still a work-in-progress and the Top Level Functional Spec (TLFS) has not been separated into x86/x64 and ARM64 areas. So additional flags may need to be updated later. This patch only changes symbol names. There are no functional changes. Signed-off-by: Michael Kelley Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman

x86/hyperv: Add interrupt handler annotations

2018-07-03T11:02:28Z

Add standard interrupt handler annotations to hyperv_vector_handler(). This does not fix any observed bug, but avoids potential removal of the code by link time optimization and makes it consistent with hv_stimer0_vector_handler in the same source file. Suggested-by: Thomas Gleixner Signed-off-by: Michael Kelley Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2018-04-09T18:42:31Z

Pull kvm updates from Paolo Bonzini: "ARM: - VHE optimizations - EL2 address space randomization - speculative execution mitigations ("variant 3a", aka execution past invalid privilege register access) - bugfixes and cleanups PPC: - improvements for the radix page fault handler for HV KVM on POWER9 s390: - more kvm stat counters - virtio gpu plumbing - documentation - facilities improvements x86: - support for VMware magic I/O port and pseudo-PMCs - AMD pause loop exiting - support for AMD core performance extensions - support for synchronous register access - expose nVMX capabilities to userspace - support for Hyper-V signaling via eventfd - use Enlightened VMCS when running on Hyper-V - allow userspace to disable MWAIT/HLT/PAUSE vmexits - usual roundup of optimizations and nested virtualization bugfixes Generic: - API selftest infrastructure (though the only tests are for x86 as of now)" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (174 commits) kvm: x86: fix a prototype warning kvm: selftests: add sync_regs_test kvm: selftests: add API testing infrastructure kvm: x86: fix a compile warning KVM: X86: Add Force Emulation Prefix for "emulate the next instruction" KVM: X86: Introduce handle_ud() KVM: vmx: unify adjacent #ifdefs x86: kvm: hide the unused 'cpu' variable KVM: VMX: remove bogus WARN_ON in handle_ept_misconfig Revert "KVM: X86: Fix SMRAM accessing even if VM is shutdown" kvm: Add emulation for movups/movupd KVM: VMX: raise internal error for exception during invalid protected mode state KVM: nVMX: Optimization: Dont set KVM_REQ_EVENT when VMExit with nested_run_pending KVM: nVMX: Require immediate-exit when event reinjected to L2 and L1 event pending KVM: x86: Fix misleading comments on handling pending exceptions KVM: x86: Rename interrupt.pending to interrupt.injected KVM: VMX: No need to clear pending NMI/interrupt on inject realmode interrupt x86/kvm: use Enlightened VMCS when running on Hyper-V x86/hyper-v: detect nested features x86/hyper-v: define struct hv_enlightened_vmcs and clean field bits ...

x86/hyper-v: detect nested features

2018-03-28T20:47:06Z

TLFS 5.0 says: "Support for an enlightened VMCS interface is reported with CPUID leaf 0x40000004. If an enlightened VMCS interface is supported, additional nested enlightenments may be discovered by reading the CPUID leaf 0x4000000A (see 2.4.11)." Signed-off-by: Vitaly Kuznetsov Reviewed-by: Michael Kelley Reviewed-by: Thomas Gleixner Signed-off-by: Radim Krčmář

x86/hyper-v: move definitions from TLFS to hyperv-tlfs.h

2018-03-28T20:47:06Z

mshyperv.h now only contains fucntions/variables we define in kernel, all definitions from TLFS should go to hyperv-tlfs.h. 'enum hv_cpuid_function' is removed as we already have this info in hyperv-tlfs.h, code in mshyperv.c is adjusted accordingly. Signed-off-by: Vitaly Kuznetsov Reviewed-by: Michael Kelley Acked-by: Thomas Gleixner Signed-off-by: Radim Krčmář

x86/hyper-v: move hyperv.h out of uapi

2018-03-28T20:47:06Z

hyperv.h is not part of uapi, there are no (known) users outside of kernel. We are making changes to this file to match current Hyper-V Hypervisor Top-Level Functional Specification (TLFS, see: https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs) and we don't want to maintain backwards compatibility. Move the file renaming to hyperv-tlfs.h to avoid confusing it with mshyperv.h. In future, all definitions from TLFS should go to it and all kernel objects should go to mshyperv.h or include/linux/hyperv.h. Signed-off-by: Vitaly Kuznetsov Acked-by: Thomas Gleixner Signed-off-by: Radim Krčmář