user/sven/linux.git/include/linux/kvm_host.h, branch v5.15.57

x86/kvm/vmx: Make noinstr clean

2022-07-23T10:53:57Z

commit 742ab6df974ae8384a2dd213db1a3a06cf6d8936 upstream. The recent mmio_stale_data fixes broke the noinstr constraints: vmlinux.o: warning: objtool: vmx_vcpu_enter_exit+0x15b: call to wrmsrl.constprop.0() leaves .noinstr.text section vmlinux.o: warning: objtool: vmx_vcpu_enter_exit+0x1bf: call to kvm_arch_has_assigned_device() leaves .noinstr.text section make it all happy again. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Greg Kroah-Hartman

kvm: add guest_state_{enter,exit}_irqoff()

2022-02-08T17:34:12Z

commit ef9989afda73332df566852d6e9ca695c05f10ce upstream. When transitioning to/from guest mode, it is necessary to inform lockdep, tracing, and RCU in a specific order, similar to the requirements for transitions to/from user mode. Additionally, it is necessary to perform vtime accounting for a window around running the guest, with RCU enabled, such that timer interrupts taken from the guest can be accounted as guest time. Most architectures don't handle all the necessary pieces, and a have a number of common bugs, including unsafe usage of RCU during the window between guest_enter() and guest_exit(). On x86, this was dealt with across commits: 87fa7f3e98a1310e ("x86/kvm: Move context tracking where it belongs") 0642391e2139a2c1 ("x86/kvm/vmx: Add hardirq tracing to guest enter/exit") 9fc975e9efd03e57 ("x86/kvm/svm: Add hardirq tracing on guest enter/exit") 3ebccdf373c21d86 ("x86/kvm/vmx: Move guest enter/exit into .noinstr.text") 135961e0a7d555fc ("x86/kvm/svm: Move guest enter/exit into .noinstr.text") 160457140187c5fb ("KVM: x86: Defer vtime accounting 'til after IRQ handling") bc908e091b326467 ("KVM: x86: Consolidate guest enter/exit logic to common helpers") ... but those fixes are specific to x86, and as the resulting logic (while correct) is split across generic helper functions and x86-specific helper functions, it is difficult to see that the entry/exit accounting is balanced. This patch adds generic helpers which architectures can use to handle guest entry/exit consistently and correctly. The guest_{enter,exit}() helpers are split into guest_timing_{enter,exit}() to perform vtime accounting, and guest_context_{enter,exit}() to perform the necessary context tracking and RCU management. The existing guest_{enter,exit}() heleprs are left as wrappers of these. Atop this, new guest_state_enter_irqoff() and guest_state_exit_irqoff() helpers are added to handle the ordering of lockdep, tracing, and RCU manageent. These are inteneded to mirror exit_to_user_mode() and enter_from_user_mode(). Subsequent patches will migrate architectures over to the new helpers, following a sequence: guest_timing_enter_irqoff(); guest_state_enter_irqoff(); < run the vcpu > guest_state_exit_irqoff(); < take any pending IRQs > guest_timing_exit_irqoff(); This sequences handles all of the above correctly, and more clearly balances the entry and exit portions, making it easier to understand. The existing helpers are marked as deprecated, and will be removed once all architectures have been converted. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland Reviewed-by: Marc Zyngier Reviewed-by: Paolo Bonzini Reviewed-by: Nicolas Saenz Julienne Message-Id: <20220201132926.3301912-2-mark.rutland@arm.com> Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman

KVM: Remove tlbs_dirty

2021-09-23T15:01:12Z

There is no user of tlbs_dirty. Signed-off-by: Lai Jiangshan Signed-off-by: Paolo Bonzini Message-Id: <20210918005636.3675-4-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini

KVM: x86: Query vcpu->vcpu_idx directly and drop its accessor

2021-09-22T14:33:11Z

Read vcpu->vcpu_idx directly instead of bouncing through the one-line wrapper, kvm_vcpu_get_idx(), and drop the wrapper. The wrapper is a remnant of the original implementation and serves no purpose; remove it before it gains more users. Back when kvm_vcpu_get_idx() was added by commit 497d72d80a78 ("KVM: Add kvm_vcpu_get_idx to get vcpu index in kvm->vcpus"), the implementation was more than just a simple wrapper as vcpu->vcpu_idx did not exist and retrieving the index meant walking over the vCPU array to find the given vCPU. When vcpu_idx was introduced by commit 8750e72a79dd ("KVM: remember position in kvm->vcpus array"), the helper was left behind, likely to avoid extra thrash (but even then there were only two users, the original arm usage having been removed at some point in the past). No functional change intended. Suggested-by: Vitaly Kuznetsov Signed-off-by: Sean Christopherson Reviewed-by: Maxim Levitsky Reviewed-by: Vitaly Kuznetsov Message-Id: <20210910183220.2397812-2-seanjc@google.com> Signed-off-by: Paolo Bonzini

Merge tag 'kvmarm-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2021-09-06T10:34:48Z

KVM/arm64 updates for 5.15 - Page ownership tracking between host EL1 and EL2 - Rely on userspace page tables to create large stage-2 mappings - Fix incompatibility between pKVM and kmemleak - Fix the PMU reset state, and improve the performance of the virtual PMU - Move over to the generic KVM entry code - Address PSCI reset issues w.r.t. save/restore - Preliminary rework for the upcoming pKVM fixed feature - A bunch of MM cleanups - a vGIC fix for timer spurious interrupts - Various cleanups

KVM: stats: Add VM stat for remote tlb flush requests

2021-09-06T10:30:45Z

Add a new stat that counts the number of times a remote TLB flush is requested, regardless of whether it kicks vCPUs out of guest mode. This allows us to look at how often flushes are initiated. Unlike remote_tlb_flush, this one applies to ARM's instruction-set-based TLB flush implementation, so apply it there too. Original-by: David Matlack Signed-off-by: Jing Zhang Message-Id: <20210817002639.3856694-1-jingzhangos@google.com> Signed-off-by: Paolo Bonzini

KVM: stats: Add halt polling related histogram stats

2021-08-20T20:06:33Z

Add three log histogram stats to record the distribution of time spent on successful polling, failed polling and VCPU wait. halt_poll_success_hist: Distribution of spent time for a successful poll. halt_poll_fail_hist: Distribution of spent time for a failed poll. halt_wait_hist: Distribution of time a VCPU has spent on waiting. Signed-off-by: Jing Zhang Message-Id: <20210802165633.1866976-6-jingzhangos@google.com> Signed-off-by: Paolo Bonzini

KVM: stats: Add halt_wait_ns stats for all architectures

2021-08-20T20:06:33Z

Add simple stats halt_wait_ns to record the time a VCPU has spent on waiting for all architectures (not just powerpc). Signed-off-by: Jing Zhang Message-Id: <20210802165633.1866976-5-jingzhangos@google.com> Signed-off-by: Paolo Bonzini

KVM: stats: Support linear and logarithmic histogram statistics

2021-08-20T20:06:32Z

Add new types of KVM stats, linear and logarithmic histogram. Histogram are very useful for observing the value distribution of time or size related stats. Signed-off-by: Jing Zhang Message-Id: <20210802165633.1866976-2-jingzhangos@google.com> Signed-off-by: Paolo Bonzini

KVM: x86/mmu: bump mmu notifier count in kvm_zap_gfn_range

2021-08-20T20:06:19Z

This together with previous patch, ensures that kvm_zap_gfn_range doesn't race with page fault running on another vcpu, and will make this page fault code retry instead. This is based on a patch suggested by Sean Christopherson: https://lkml.org/lkml/2021/7/22/1025 Suggested-by: Sean Christopherson Signed-off-by: Maxim Levitsky Message-Id: <20210810205251.424103-5-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini