1 files changed, 3 insertions, 41 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index be5ee9f7f..76d1ec291 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -43,7 +43,6 @@
 #include <linux/printk.h>
 #include <linux/userfaultfd_k.h>
 #include <linux/moduleparam.h>
-#include <linux/ksm.h>
 
 #include <asm/uaccess.h>
 #include <asm/cacheflush.h>
@@ -293,7 +292,6 @@ static struct vm_area_struct *remove_vma(struct vm_area_struct *vma)
 	if (vma->vm_file)
 		fput(vma->vm_file);
 	mpol_put(vma_policy(vma));
-	uksm_remove_vma(vma);
 	kmem_cache_free(vm_area_cachep, vma);
 	return next;
 }
@@ -758,16 +756,9 @@ int vma_adjust(struct vm_area_struct *vma, unsigned long start,
 	long adjust_next = 0;
 	int remove_next = 0;
 
-/*
- * to avoid deadlock, ksm_remove_vma must be done before any spin_lock is
- * acquired
- */
-	uksm_remove_vma(vma);
-
 	if (next && !insert) {
 		struct vm_area_struct *exporter = NULL;
 
-		uksm_remove_vma(next);
 		if (end >= next->vm_end) {
 			/*
 			 * vma expands, overlapping all the next, and
@@ -861,7 +852,6 @@ again:			remove_next = 1 + (end > next->vm_end);
 		end_changed = true;
 	}
 	vma->vm_pgoff = pgoff;
-
 	if (adjust_next) {
 		next->vm_start += adjust_next << PAGE_SHIFT;
 		next->vm_pgoff += adjust_next;
@@ -932,22 +922,16 @@ again:			remove_next = 1 + (end > next->vm_end);
 		 * up the code too much to do both in one go.
 		 */
 		next = vma->vm_next;
-		if (remove_next == 2) {
-			uksm_remove_vma(next);
+		if (remove_next == 2)
 			goto again;
-		} else if (next) {
+		else if (next)
 			vma_gap_update(next);
-		} else {
+		else
 			mm->highest_vm_end = end;
-		}
-	} else {
-		if (next && !insert)
-			uksm_vma_add_new(next);
 	}
 	if (insert && file)
 		uprobe_mmap(insert);
 
-	uksm_vma_add_new(vma);
 	validate_mm(mm);
 
 	return 0;
@@ -1332,9 +1316,6 @@ unsigned long do_mmap(struct file *file, unsigned long addr,
 	vm_flags |= calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags) |
 			mm->def_flags | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
 
-	/* If uksm is enabled, we add VM_MERGABLE to new VMAs. */
-	uksm_vm_flags_mod(&vm_flags);
-
 	if (flags & MAP_LOCKED)
 		if (!can_do_mlock())
 			return -EPERM;
@@ -1673,7 +1654,6 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
 			allow_write_access(file);
 	}
 	file = vma->vm_file;
-	uksm_vma_add_new(vma);
 out:
 	perf_event_mmap(vma);
 
@@ -1715,7 +1695,6 @@ allow_write_and_free_vma:
 	if (vm_flags & VM_DENYWRITE)
 		allow_write_access(file);
 free_vma:
-	uksm_remove_vma(vma);
 	kmem_cache_free(vm_area_cachep, vma);
 unacct_error:
 	if (charged)
@@ -2511,8 +2490,6 @@ static int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma,
 	else
 		err = vma_adjust(vma, vma->vm_start, addr, vma->vm_pgoff, new);
 
-	uksm_vma_add_new(new);
-
 	/* Success. */
 	if (!err)
 		return 0;
@@ -2773,7 +2750,6 @@ static unsigned long do_brk(unsigned long addr, unsigned long len)
 		return addr;
 
 	flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
-	uksm_vm_flags_mod(&flags);
 
 	error = get_unmapped_area(NULL, addr, len, 0, MAP_FIXED);
 	if (offset_in_page(error))
@@ -2831,7 +2807,6 @@ static unsigned long do_brk(unsigned long addr, unsigned long len)
 	vma->vm_flags = flags;
 	vma->vm_page_prot = vm_get_page_prot(flags);
 	vma_link(mm, vma, prev, rb_link, rb_parent);
-	uksm_vma_add_new(vma);
 out:
 	perf_event_mmap(vma);
 	mm->total_vm += len >> PAGE_SHIFT;
@@ -2868,12 +2843,6 @@ void exit_mmap(struct mm_struct *mm)
 	/* mm's last user has gone, and its about to be pulled down */
 	mmu_notifier_release(mm);
 
-	/*
-	 * Taking write lock on mmap_sem does not harm others,
-	 * but it's crucial for uksm to avoid races.
-	 */
-	down_write(&mm->mmap_sem);
-
 	if (mm->locked_vm) {
 		vma = mm->mmap;
 		while (vma) {
@@ -2909,11 +2878,6 @@ void exit_mmap(struct mm_struct *mm)
 		vma = remove_vma(vma);
 	}
 	vm_unacct_memory(nr_accounted);
-
-	mm->mmap = NULL;
-	mm->mm_rb = RB_ROOT;
-	vmacache_invalidate(mm);
-	up_write(&mm->mmap_sem);
 }
 
 /* Insert vm structure into process list sorted by address
@@ -3023,7 +2987,6 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
 			new_vma->vm_ops->open(new_vma);
 		vma_link(mm, new_vma, prev, rb_link, rb_parent);
 		*need_rmap_locks = false;
-		uksm_vma_add_new(new_vma);
 	}
 	return new_vma;
 
@@ -3153,7 +3116,6 @@ static struct vm_area_struct *__install_special_mapping(
 	vm_stat_account(mm, vma->vm_flags, len >> PAGE_SHIFT);
 
 	perf_event_mmap(vma);
-	uksm_vma_add_new(vma);
 
 	return vma;