| Message ID | 20210112181041.356734-9-bgardon@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Allow parallel page faults with TDP MMU | expand |
On Tue, Jan 12, 2021, Ben Gardon wrote: > Add lockdep to __tdp_mmu_set_spte to ensure that SPTEs are only modified > under the MMU lock. This lockdep will be updated in future commits to > reflect and validate changes to the TDP MMU's synchronization strategy. I'd omit the "updated in future commits" justification. IMO this is a good change even if we never build on it, and the extra justification would be confusing if this is merged separately from the parallelization patches. > No functional change intended. > > Reviewed-by: Peter Feiner <pfeiner@google.com> > > Signed-off-by: Ben Gardon <bgardon@google.com> Reviewed-by: Sean Christopherson <seanjc@google.com>
On 12/01/21 19:10, Ben Gardon wrote: > Add lockdep to __tdp_mmu_set_spte to ensure that SPTEs are only modified > under the MMU lock. This lockdep will be updated in future commits to > reflect and validate changes to the TDP MMU's synchronization strategy. > > No functional change intended. > > Reviewed-by: Peter Feiner <pfeiner@google.com> > > Signed-off-by: Ben Gardon <bgardon@google.com> > --- > arch/x86/kvm/mmu/tdp_mmu.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c > index b033da8243fc..411938e97a00 100644 > --- a/arch/x86/kvm/mmu/tdp_mmu.c > +++ b/arch/x86/kvm/mmu/tdp_mmu.c > @@ -381,6 +381,8 @@ static inline void __tdp_mmu_set_spte(struct kvm *kvm, struct tdp_iter *iter, > struct kvm_mmu_page *root = sptep_to_sp(root_pt); > int as_id = kvm_mmu_page_as_id(root); > > + lockdep_assert_held(&kvm->mmu_lock); > + > WRITE_ONCE(*iter->sptep, new_spte); > > __handle_changed_spte(kvm, as_id, iter->gfn, iter->old_spte, new_spte, > Queued, thanks. Paolo
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index b033da8243fc..411938e97a00 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -381,6 +381,8 @@ static inline void __tdp_mmu_set_spte(struct kvm *kvm, struct tdp_iter *iter, struct kvm_mmu_page *root = sptep_to_sp(root_pt); int as_id = kvm_mmu_page_as_id(root); + lockdep_assert_held(&kvm->mmu_lock); + WRITE_ONCE(*iter->sptep, new_spte); __handle_changed_spte(kvm, as_id, iter->gfn, iter->old_spte, new_spte,