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-rw-r--r--drivers/kvm/kvm.h2
-rw-r--r--drivers/kvm/kvm_main.c38
2 files changed, 3 insertions, 37 deletions
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h
index ee9f8bd..351da40 100644
--- a/drivers/kvm/kvm.h
+++ b/drivers/kvm/kvm.h
@@ -411,8 +411,6 @@ struct kvm {
int n_free_mmu_pages;
struct hlist_head mmu_page_hash[KVM_NUM_MMU_PAGES];
struct kvm_vcpu *vcpus[KVM_MAX_VCPUS];
- int memory_config_version;
- int busy;
unsigned long rmap_overflow;
struct list_head vm_list;
struct file *filp;
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 9dffbbe..8da13a4 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -679,7 +679,6 @@ static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
unsigned long i;
struct kvm_memory_slot *memslot;
struct kvm_memory_slot old, new;
- int memory_config_version;
r = -EINVAL;
/* General sanity checks */
@@ -699,10 +698,8 @@ static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
if (!npages)
mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
-raced:
mutex_lock(&kvm->lock);
- memory_config_version = kvm->memory_config_version;
new = old = *memslot;
new.base_gfn = base_gfn;
@@ -725,11 +722,6 @@ raced:
(base_gfn >= s->base_gfn + s->npages)))
goto out_unlock;
}
- /*
- * Do memory allocations outside lock. memory_config_version will
- * detect any races.
- */
- mutex_unlock(&kvm->lock);
/* Deallocate if slot is being removed */
if (!npages)
@@ -746,14 +738,14 @@ raced:
new.phys_mem = vmalloc(npages * sizeof(struct page *));
if (!new.phys_mem)
- goto out_free;
+ goto out_unlock;
memset(new.phys_mem, 0, npages * sizeof(struct page *));
for (i = 0; i < npages; ++i) {
new.phys_mem[i] = alloc_page(GFP_HIGHUSER
| __GFP_ZERO);
if (!new.phys_mem[i])
- goto out_free;
+ goto out_unlock;
set_page_private(new.phys_mem[i],0);
}
}
@@ -764,27 +756,14 @@ raced:
new.dirty_bitmap = vmalloc(dirty_bytes);
if (!new.dirty_bitmap)
- goto out_free;
+ goto out_unlock;
memset(new.dirty_bitmap, 0, dirty_bytes);
}
- mutex_lock(&kvm->lock);
-
- if (memory_config_version != kvm->memory_config_version) {
- mutex_unlock(&kvm->lock);
- kvm_free_physmem_slot(&new, &old);
- goto raced;
- }
-
- r = -EAGAIN;
- if (kvm->busy)
- goto out_unlock;
-
if (mem->slot >= kvm->nmemslots)
kvm->nmemslots = mem->slot + 1;
*memslot = new;
- ++kvm->memory_config_version;
kvm_mmu_slot_remove_write_access(kvm, mem->slot);
kvm_flush_remote_tlbs(kvm);
@@ -796,7 +775,6 @@ raced:
out_unlock:
mutex_unlock(&kvm->lock);
-out_free:
kvm_free_physmem_slot(&new, &old);
out:
return r;
@@ -815,12 +793,6 @@ static int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
mutex_lock(&kvm->lock);
- /*
- * Prevent changes to guest memory configuration even while the lock
- * is not taken.
- */
- ++kvm->busy;
- mutex_unlock(&kvm->lock);
r = -EINVAL;
if (log->slot >= KVM_MEMORY_SLOTS)
goto out;
@@ -841,18 +813,14 @@ static int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
/* If nothing is dirty, don't bother messing with page tables. */
if (any) {
- mutex_lock(&kvm->lock);
kvm_mmu_slot_remove_write_access(kvm, log->slot);
kvm_flush_remote_tlbs(kvm);
memset(memslot->dirty_bitmap, 0, n);
- mutex_unlock(&kvm->lock);
}
r = 0;
out:
- mutex_lock(&kvm->lock);
- --kvm->busy;
mutex_unlock(&kvm->lock);
return r;
}