On 28/02/23 7:01 am, Yuan Yao wrote:
On Sat, Feb 25, 2023 at 08:47:59PM +0000, Shivam Kumar wrote:Call update_dirty_quota whenever a page is marked dirty with appropriate arch-specific page size. Process the KVM request KVM_REQ_DIRTY_QUOTA_EXIT (raised by update_dirty_quota) to exit to userspace with exit reason KVM_EXIT_DIRTY_QUOTA_EXHAUSTED. Suggested-by: Shaju Abraham <shaju.abraham@xxxxxxxxxxx> Suggested-by: Manish Mishra <manish.mishra@xxxxxxxxxxx> Co-developed-by: Anurag Madnawat <anurag.madnawat@xxxxxxxxxxx> Signed-off-by: Anurag Madnawat <anurag.madnawat@xxxxxxxxxxx> Signed-off-by: Shivam Kumar <shivam.kumar1@xxxxxxxxxxx> --- arch/x86/kvm/Kconfig | 1 + arch/x86/kvm/mmu/mmu.c | 8 +++++++- arch/x86/kvm/mmu/spte.c | 3 +++ arch/x86/kvm/mmu/tdp_mmu.c | 3 +++ arch/x86/kvm/vmx/vmx.c | 5 +++++ arch/x86/kvm/x86.c | 16 ++++++++++++++++ arch/x86/kvm/xen.c | 12 +++++++++++- 7 files changed, 46 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index 8e578311ca9d..8621a9512572 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -48,6 +48,7 @@ config KVM select KVM_VFIO select SRCU select INTERVAL_TREE + select HAVE_KVM_DIRTY_QUOTA select HAVE_KVM_PM_NOTIFIER if PM select KVM_GENERIC_HARDWARE_ENABLING help diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index c8ebe542c565..e0c8348ecdf1 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -3323,8 +3323,14 @@ fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault, if (!try_cmpxchg64(sptep, &old_spte, new_spte)) return false; - if (is_writable_pte(new_spte) && !is_writable_pte(old_spte)) + if (is_writable_pte(new_spte) && !is_writable_pte(old_spte)) { +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA + struct kvm_mmu_page *sp = sptep_to_sp(sptep); + + update_dirty_quota(vcpu->kvm, (1L << SPTE_LEVEL_SHIFT(sp->role.level))); +#endif mark_page_dirty_in_slot(vcpu->kvm, fault->slot, fault->gfn);Possible to call update_dirty_quota() from mark_page_dirty_in_slot() ? Then other Architectures can be covered yet.
As Marc commented on the first patch of this patchset, mark_page_dirty_in_slot can be called multiple times for the same page, e.g. in the case of PML for nested guests. If bitmap-based dirty tracking is not enabled, we might not be able to handle those cases without adding an extra param (which can tell us whether a dirty quota update is required or not) in mark_page_dirty_in_slot. Thanks.
Thanks, Shivam
