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Diffstat (limited to 'mm/vmalloc.c')
-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);