diff mbox series

[V5,5/5] KVM: Small Refactoring to kvm_free_memslot

Message ID 20181026151223.16810-6-ahmedsoliman0x666@gmail.com
State New, archived
Headers show
Series KVM: X86: Introducing ROE Protection Kernel Hardening | expand

Commit Message

Ahmed Soliman Oct. 26, 2018, 3:12 p.m. UTC
This should be a little bit more readable and prone to memory leaks

Signed-off-by: Ahmed Abd El Mawgood <ahmedsoliman0x666@gmail.com>
---
 virt/kvm/kvm_main.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

Comments

Sean Christopherson Oct. 29, 2018, 4:51 p.m. UTC | #1
On Fri, Oct 26, 2018 at 05:12:23PM +0200, Ahmed Abd El Mawgood wrote:
> This should be a little bit more readable and prone to memory leaks

Describe what is being, both in the subject line and continuing on in
the full changelog, e.g. "Small Refactoring to kvm_free_memslot" doesn't
provide any clue as to what is being done.  And this is not what I would
describe as refactoring, e.g. verifying the new behavior means tracing
through its impact on __kvm_set_memory_region().

Lastly, this should be sent as a separate patch.  There is no dependency
on the ROE code and if it actually addresses a potential memory leak (I
haven't actually reviewed the code itself) it should go in sooner rather
than later.

> 
> Signed-off-by: Ahmed Abd El Mawgood <ahmedsoliman0x666@gmail.com>
> ---
>  virt/kvm/kvm_main.c | 15 +++++++--------
>  1 file changed, 7 insertions(+), 8 deletions(-)
> 
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 2d3011e8490e..79c98db03c84 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -550,11 +550,11 @@ static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
>   * Free any memory in @free but not in @dont.
>   */
>  static void kvm_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
> -			      struct kvm_memory_slot *dont)
> +			      struct kvm_memory_slot *dont,
> +			      enum kvm_mr_change change)
>  {
> +	if (change == KVM_MR_DELETE) {
>  #ifdef CONFIG_KVM_ROE
> -	if (!dont) {
> -		//TODO still this might leak
>  		struct protected_chunk *pos, *n;
>  		struct list_head *head = free->prot_list;
>  		kvfree(free->roe_bitmap);
> @@ -564,10 +564,9 @@ static void kvm_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
>  			kvfree(pos);
>  		}
>  		kvfree(free->prot_list);
> -	}
>  #endif
> -	if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
>  		kvm_destroy_dirty_bitmap(free);
> +	}
>  
>  	kvm_arch_free_memslot(kvm, free, dont);
>  
> @@ -582,7 +581,7 @@ static void kvm_free_memslots(struct kvm *kvm, struct kvm_memslots *slots)
>  		return;
>  
>  	kvm_for_each_memslot(memslot, slots)
> -		kvm_free_memslot(kvm, memslot, NULL);
> +		kvm_free_memslot(kvm, memslot, NULL, KVM_MR_DELETE);
>  
>  	kvfree(slots);
>  }
> @@ -1100,14 +1099,14 @@ int __kvm_set_memory_region(struct kvm *kvm,
>  
>  	kvm_arch_commit_memory_region(kvm, mem, &old, &new, change);
>  
> -	kvm_free_memslot(kvm, &old, &new);
> +	kvm_free_memslot(kvm, &old, &new, change);
>  	kvfree(old_memslots);
>  	return 0;
>  
>  out_slots:
>  	kvfree(slots);
>  out_free:
> -	kvm_free_memslot(kvm, &new, &old);
> +	kvm_free_memslot(kvm, &new, &old, change);
>  out:
>  	return r;
>  }
> -- 
> 2.18.1
>
diff mbox series

Patch

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 2d3011e8490e..79c98db03c84 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -550,11 +550,11 @@  static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
  * Free any memory in @free but not in @dont.
  */
 static void kvm_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
-			      struct kvm_memory_slot *dont)
+			      struct kvm_memory_slot *dont,
+			      enum kvm_mr_change change)
 {
+	if (change == KVM_MR_DELETE) {
 #ifdef CONFIG_KVM_ROE
-	if (!dont) {
-		//TODO still this might leak
 		struct protected_chunk *pos, *n;
 		struct list_head *head = free->prot_list;
 		kvfree(free->roe_bitmap);
@@ -564,10 +564,9 @@  static void kvm_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
 			kvfree(pos);
 		}
 		kvfree(free->prot_list);
-	}
 #endif
-	if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
 		kvm_destroy_dirty_bitmap(free);
+	}
 
 	kvm_arch_free_memslot(kvm, free, dont);
 
@@ -582,7 +581,7 @@  static void kvm_free_memslots(struct kvm *kvm, struct kvm_memslots *slots)
 		return;
 
 	kvm_for_each_memslot(memslot, slots)
-		kvm_free_memslot(kvm, memslot, NULL);
+		kvm_free_memslot(kvm, memslot, NULL, KVM_MR_DELETE);
 
 	kvfree(slots);
 }
@@ -1100,14 +1099,14 @@  int __kvm_set_memory_region(struct kvm *kvm,
 
 	kvm_arch_commit_memory_region(kvm, mem, &old, &new, change);
 
-	kvm_free_memslot(kvm, &old, &new);
+	kvm_free_memslot(kvm, &old, &new, change);
 	kvfree(old_memslots);
 	return 0;
 
 out_slots:
 	kvfree(slots);
 out_free:
-	kvm_free_memslot(kvm, &new, &old);
+	kvm_free_memslot(kvm, &new, &old, change);
 out:
 	return r;
 }