On 13.04.21 09:16, Wanpeng Li wrote:
The bugzilla https://bugzilla.kernel.org/show_bug.cgi?id=209831 reported that the guest time remains 0 when running a while true loop in the guest. The commit 87fa7f3e98a131 ("x86/kvm: Move context tracking where it belongs") moves guest_exit_irqoff() close to vmexit breaks the tick-based time accouting when the ticks that happen after IRQs are disabled are incorrectly accounted to the host/system time. This is because we exit the guest state too early. This patchset splits both context tracking logic and the time accounting logic from guest_enter/exit_irqoff(), keep context tracking around the actual vmentry/exit code, have the virt time specific helpers which can be placed at the proper spots in kvm. In addition, it will not break the world outside of x86. v1 -> v2: * split context_tracking from guest_enter/exit_irqoff * provide separate vtime accounting functions for consistent * place the virt time specific helpers at the proper splot Suggested-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Sean Christopherson <seanjc@xxxxxxxxxx> Cc: Michael Tokarev <mjt@xxxxxxxxxx> Wanpeng Li (3): context_tracking: Split guest_enter/exit_irqoff context_tracking: Provide separate vtime accounting functions x86/kvm: Fix vtime accounting arch/x86/kvm/svm/svm.c | 6 ++- arch/x86/kvm/vmx/vmx.c | 6 ++- arch/x86/kvm/x86.c | 1 + include/linux/context_tracking.h | 84 +++++++++++++++++++++++++++++++--------- 4 files changed, 74 insertions(+), 23 deletions(-)
The non CONFIG_VIRT_CPU_ACCOUNTING_GEN look good.
