summaryrefslogtreecommitdiff
path: root/arch/x86/kvm/x86.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2021-05-09 12:52:25 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-05-09 12:52:25 -0700
commitdd3e4012dd360873f95bbe7fe2eb65d951781803 (patch)
treeb7a705c5cbabe0392fb6679987bec2943de4130e /arch/x86/kvm/x86.c
parentb741596468b010af2846b75f5e75a842ce344a6e (diff)
parentbc908e091b3264672889162733020048901021fb (diff)
Merge tag 'x86_urgent_for_v5.13_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov: "A bunch of things accumulated for x86 in the last two weeks: - Fix guest vtime accounting so that ticks happening while the guest is running can also be accounted to it. Along with a consolidation to the guest-specific context tracking helpers. - Provide for the host NMI handler running after a VMX VMEXIT to be able to run on the kernel stack correctly. - Initialize MSR_TSC_AUX when RDPID is supported and not RDTSCP (virt relevant - real hw supports both) - A code generation improvement to TASK_SIZE_MAX through the use of alternatives - The usual misc and related cleanups and improvements" * tag 'x86_urgent_for_v5.13_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: KVM: x86: Consolidate guest enter/exit logic to common helpers context_tracking: KVM: Move guest enter/exit wrappers to KVM's domain context_tracking: Consolidate guest enter/exit wrappers sched/vtime: Move guest enter/exit vtime accounting to vtime.h sched/vtime: Move vtime accounting external declarations above inlines KVM: x86: Defer vtime accounting 'til after IRQ handling context_tracking: Move guest exit vtime accounting to separate helpers context_tracking: Move guest exit context tracking to separate helpers KVM/VMX: Invoke NMI non-IST entry instead of IST entry x86/cpu: Remove write_tsc() and write_rdtscp_aux() wrappers x86/cpu: Initialize MSR_TSC_AUX if RDTSCP *or* RDPID is supported x86/resctrl: Fix init const confusion x86: Delete UD0, UD1 traces x86/smpboot: Remove duplicate includes x86/cpu: Use alternative to generate the TASK_SIZE_MAX constant
Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r--arch/x86/kvm/x86.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index cebdaa1e3cf5..6eda2834fc05 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9315,6 +9315,15 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
local_irq_disable();
kvm_after_interrupt(vcpu);
+ /*
+ * Wait until after servicing IRQs to account guest time so that any
+ * ticks that occurred while running the guest are properly accounted
+ * to the guest. Waiting until IRQs are enabled degrades the accuracy
+ * of accounting via context tracking, but the loss of accuracy is
+ * acceptable for all known use cases.
+ */
+ vtime_account_guest_exit();
+
if (lapic_in_kernel(vcpu)) {
s64 delta = vcpu->arch.apic->lapic_timer.advance_expire_delta;
if (delta != S64_MIN) {