From e1eed5847b09fe41d4db4b86f9d840aba869c905 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Thu, 1 Apr 2021 17:56:58 -0700 Subject: [PATCH] KVM: x86/mmu: Allow yielding during MMU notifier unmap/zap, if possible Let the TDP MMU yield when unmapping a range in response to a MMU notification, if yielding is allowed by said notification. There is no reason to disallow yielding in this case, and in theory the range being invalidated could be quite large. Cc: Ben Gardon Signed-off-by: Sean Christopherson Message-Id: <20210402005658.3024832-11-seanjc@google.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu/tdp_mmu.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index ea15f3098eb2..10cb16c55dd0 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -880,7 +880,7 @@ bool kvm_tdp_mmu_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range, for_each_tdp_mmu_root(kvm, root, range->slot->as_id) flush |= zap_gfn_range(kvm, root, range->start, range->end, - false, flush); + range->may_block, flush); return flush; } @@ -898,6 +898,10 @@ static __always_inline bool kvm_tdp_mmu_handle_gfn(struct kvm *kvm, rcu_read_lock(); + /* + * Don't support rescheduling, none of the MMU notifiers that funnel + * into this helper allow blocking; it'd be dead, wasteful code. + */ for_each_tdp_mmu_root(kvm, root, range->slot->as_id) { tdp_root_for_each_leaf_pte(iter, root, range->start, range->end) ret |= handler(kvm, &iter, range); -- GitLab