KVM: Fix memory slot management functions for guest smp

The memory slot management functions were oriented against vcpu 0, where
they should be kvm-wide.  This causes hangs starting X on guest smp.

Fix by making the functions (and resultant tail in the mmu) non-vcpu-specific.
Unfortunately this reduces the efficiency of the mmu object cache a bit.  We
may have to revisit this later.

Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 9 insertions, 59 deletions

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 1b206f197c6b..05f0418f2195 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -238,23 +238,6 @@ static void vcpu_load(struct kvm_vcpu *vcpu)
         kvm_arch_ops->vcpu_load(vcpu);
 }
 
-/*
- * Switches to specified vcpu, until a matching vcpu_put(). Will return NULL
- * if the slot is not populated.
- */
-static struct kvm_vcpu *vcpu_load_slot(struct kvm *kvm, int slot)
-{
-        struct kvm_vcpu *vcpu = &kvm->vcpus[slot];
-
-        mutex_lock(&vcpu->mutex);
-        if (!vcpu->vmcs) {
-                mutex_unlock(&vcpu->mutex);
-                return NULL;
-        }
-        kvm_arch_ops->vcpu_load(vcpu);
-        return vcpu;
-}
-
 static void vcpu_put(struct kvm_vcpu *vcpu)
 {
         kvm_arch_ops->vcpu_put(vcpu);
@@ -663,13 +646,6 @@ void fx_init(struct kvm_vcpu *vcpu)
 }
 EXPORT_SYMBOL_GPL(fx_init);
 
-static void do_remove_write_access(struct kvm_vcpu *vcpu, int slot)
-{
-        spin_lock(&vcpu->kvm->lock);
-        kvm_mmu_slot_remove_write_access(vcpu, slot);
-        spin_unlock(&vcpu->kvm->lock);
-}
-
 /*
  * Allocate some memory and give it an address in the guest physical address
  * space.
@@ -792,19 +768,10 @@ raced:
         *memslot = new;
         ++kvm->memory_config_version;
 
-        spin_unlock(&kvm->lock);
-
-        for (i = 0; i < KVM_MAX_VCPUS; ++i) {
-                struct kvm_vcpu *vcpu;
+        kvm_mmu_slot_remove_write_access(kvm, mem->slot);
+        kvm_flush_remote_tlbs(kvm);
 
-                vcpu = vcpu_load_slot(kvm, i);
-                if (!vcpu)
-                        continue;
-                if (new.flags & KVM_MEM_LOG_DIRTY_PAGES)
-                        do_remove_write_access(vcpu, mem->slot);
-                kvm_mmu_reset_context(vcpu);
-                vcpu_put(vcpu);
-        }
+        spin_unlock(&kvm->lock);
 
         kvm_free_physmem_slot(&old, &new);
         return 0;
@@ -826,7 +793,6 @@ static int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
         struct kvm_memory_slot *memslot;
         int r, i;
         int n;
-        int cleared;
         unsigned long any = 0;
 
         spin_lock(&kvm->lock);
@@ -855,23 +821,11 @@ static int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
                 goto out;
 
-        if (any) {
-                cleared = 0;
-                for (i = 0; i < KVM_MAX_VCPUS; ++i) {
-                        struct kvm_vcpu *vcpu;
-
-                        vcpu = vcpu_load_slot(kvm, i);
-                        if (!vcpu)
-                                continue;
-                        if (!cleared) {
-                                do_remove_write_access(vcpu, log->slot);
-                                memset(memslot->dirty_bitmap, 0, n);
-                                cleared = 1;
-                        }
-                        kvm_arch_ops->tlb_flush(vcpu);
-                        vcpu_put(vcpu);
-                }
-        }
+        spin_lock(&kvm->lock);
+        kvm_mmu_slot_remove_write_access(kvm, log->slot);
+        kvm_flush_remote_tlbs(kvm);
+        memset(memslot->dirty_bitmap, 0, n);
+        spin_unlock(&kvm->lock);
 
         r = 0;
 
@@ -920,13 +874,9 @@ static int kvm_vm_ioctl_set_memory_alias(struct kvm *kvm,
                         break;
         kvm->naliases = n;
 
-        spin_unlock(&kvm->lock);
+        kvm_mmu_zap_all(kvm);
 
-        vcpu_load(&kvm->vcpus[0]);
-        spin_lock(&kvm->lock);
-        kvm_mmu_zap_all(&kvm->vcpus[0]);
         spin_unlock(&kvm->lock);
-        vcpu_put(&kvm->vcpus[0]);
 
         return 0;