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Diffstat (limited to 'mm')
-rw-r--r--mm/vmalloc.c29
1 files changed, 7 insertions, 22 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 63a5f502da08..12bd82e6554e 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -603,26 +603,6 @@ static void unmap_vmap_area(struct vmap_area *va)
 	vunmap_page_range(va->va_start, va->va_end);
 }
 
-static void vmap_debug_free_range(unsigned long start, unsigned long end)
-{
-	/*
-	 * Unmap page tables and force a TLB flush immediately if pagealloc
-	 * debugging is enabled.  This catches use after free bugs similarly to
-	 * those in linear kernel virtual address space after a page has been
-	 * freed.
-	 *
-	 * All the lazy freeing logic is still retained, in order to minimise
-	 * intrusiveness of this debugging feature.
-	 *
-	 * This is going to be *slow* (linear kernel virtual address debugging
-	 * doesn't do a broadcast TLB flush so it is a lot faster).
-	 */
-	if (debug_pagealloc_enabled()) {
-		vunmap_page_range(start, end);
-		flush_tlb_kernel_range(start, end);
-	}
-}
-
 /*
  * lazy_max_pages is the maximum amount of virtual address space we gather up
  * before attempting to purge with a TLB flush.
@@ -756,6 +736,9 @@ static void free_unmap_vmap_area(struct vmap_area *va)
 {
 	flush_cache_vunmap(va->va_start, va->va_end);
 	unmap_vmap_area(va);
+	if (debug_pagealloc_enabled())
+		flush_tlb_kernel_range(va->va_start, va->va_end);
+
 	free_vmap_area_noflush(va);
 }
 
@@ -1053,6 +1036,10 @@ static void vb_free(const void *addr, unsigned long size)
 
 	vunmap_page_range((unsigned long)addr, (unsigned long)addr + size);
 
+	if (debug_pagealloc_enabled())
+		flush_tlb_kernel_range((unsigned long)addr,
+					(unsigned long)addr + size);
+
 	spin_lock(&vb->lock);
 
 	/* Expand dirty range */
@@ -1142,7 +1129,6 @@ void vm_unmap_ram(const void *mem, unsigned int count)
 	BUG_ON(!PAGE_ALIGNED(addr));
 
 	debug_check_no_locks_freed(mem, size);
-	vmap_debug_free_range(addr, addr+size);
 
 	if (likely(count <= VMAP_MAX_ALLOC)) {
 		vb_free(mem, size);
@@ -1499,7 +1485,6 @@ struct vm_struct *remove_vm_area(const void *addr)
 		va->flags |= VM_LAZY_FREE;
 		spin_unlock(&vmap_area_lock);
 
-		vmap_debug_free_range(va->va_start, va->va_end);
 		kasan_free_shadow(vm);
 		free_unmap_vmap_area(va);