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Peter Anvin" , Vitaly Kuznetsov , Kiryl Shutsemau , Rick Edgecombe , David Hildenbrand , kvm@vger.kernel.org, linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="us-ascii" On Thu, Sep 10, 2026, Marco Elver wrote: > kvm_swap_active_memslots() updates kvm->memslots[as_id] while holding both > kvm->slots_lock and kvm->slots_arch_lock. Holding either lock guarantees > that memslots cannot be concurrently modified. Sure, but that's irrelevant. The goal of the srcu_dereference_check() is to ensure that readers see a stable view of the VM's overall memory, not simply that kvm->memslots can't be written. > Allow reading memslots in __kvm_memslots() when kvm->slots_arch_lock is > held. Why? > > Signed-off-by: Marco Elver > --- > include/linux/kvm_host.h | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index 03bfc92864b6..5ed8260ef01f 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -1089,6 +1089,7 @@ static inline struct kvm_memslots *__kvm_memslots(struct kvm *kvm, int as_id) > as_id = array_index_nospec(as_id, KVM_MAX_NR_ADDRESS_SPACES); > return srcu_dereference_check(kvm->memslots[as_id], &kvm->srcu, > lockdep_is_held(&kvm->slots_lock) || > + lockdep_is_held(&kvm->slots_arch_lock) || > !refcount_read(&kvm->users_count)); > } > > -- > 2.55.0.1003.g10538fe699-goog >