---
 mm/vmalloc.c |   35 +++++++++++++++++++++++++++++------
 1 file changed, 29 insertions(+), 6 deletions(-)

Index: linux-2.6/mm/vmalloc.c
===================================================================
--- linux-2.6.orig/mm/vmalloc.c	2007-09-17 17:08:25.000000000 -0700
+++ linux-2.6/mm/vmalloc.c	2007-09-17 17:10:19.000000000 -0700
@@ -385,6 +385,21 @@ struct vm_struct *remove_vm_area(const v
 	return v;
 }
 
+struct vfree_work_struct {
+	struct work_struct work;
+	int mode;
+};
+
+static void __vunmap(const void *, int);
+
+static void vfree_work(struct work_struct *w)
+{
+	struct vfree_work_struct *vws =
+			container_of(w, struct vfree_work_struct, work);
+
+	__vunmap(vws, vws->mode);
+}
+
 static void __vunmap(const void *addr, int deallocate_pages)
 {
 	struct vm_struct *area;
@@ -398,6 +413,20 @@ static void __vunmap(const void *addr, i
 		return;
 	}
 
+	if (in_interrupt()) {
+		struct vfree_work_struct *vws = (void *)addr;
+
+		/*
+		 * The object is unused and we have at least a page at
+		 * addr. So we can just use the area to a work_struct
+		 * in there to defer the free until a time when interrupts
+		 * are enabled and we can safely acquire locks.
+		 */
+		INIT_WORK(&vws->work, vfree_work);
+		vws->mode = deallocate_pages;
+		schedule_work(&vws->work);
+		return;
+	}
 	area = remove_vm_area(addr);
 	if (unlikely(!area)) {
 		printk(KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
@@ -436,12 +465,9 @@ static void __vunmap(const void *addr, i
  *	Free the virtually contiguous memory area starting at @addr, as
  *	obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is
  *	NULL, no operation is performed.
- *
- *	Must not be called in interrupt context.
  */
 void vfree(const void *addr)
 {
-	BUG_ON(in_interrupt());
 	__vunmap(addr, 1);
 }
 EXPORT_SYMBOL(vfree);
@@ -452,12 +478,9 @@ EXPORT_SYMBOL(vfree);
  *
  *	Free the virtually contiguous memory area starting at @addr,
  *	which was created from the page array passed to vmap().
- *
- *	Must not be called in interrupt context.
  */
 void vunmap(const void *addr)
 {
-	BUG_ON(in_interrupt());
 	__vunmap(addr, 0);
 }
 EXPORT_SYMBOL(vunmap);