x86/debug: Fix DR_STEP vs ptrace_get_debugreg(6)

[linux-2.6-microblaze.git] / fs / userfaultfd.c

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 0e4a383..000b457 100644 (file)
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -601,8 +601,6 @@ static void userfaultfd_event_wait_completion(struct userfaultfd_ctx *ctx,
 
                /* the various vma->vm_userfaultfd_ctx still points to it */
                mmap_write_lock(mm);
-               /* no task can run (and in turn coredump) yet */
-               VM_WARN_ON(!mmget_still_valid(mm));
                for (vma = mm->mmap; vma; vma = vma->vm_next)
                        if (vma->vm_userfaultfd_ctx.ctx == release_new_ctx) {
                                vma->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX;
@@ -842,7 +840,6 @@ static int userfaultfd_release(struct inode *inode, struct file *file)
        /* len == 0 means wake all */
        struct userfaultfd_wake_range range = { .len = 0, };
        unsigned long new_flags;
-       bool still_valid;
 
        WRITE_ONCE(ctx->released, true);
 
@@ -858,7 +855,6 @@ static int userfaultfd_release(struct inode *inode, struct file *file)
         * taking the mmap_lock for writing.
         */
        mmap_write_lock(mm);
-       still_valid = mmget_still_valid(mm);
        prev = NULL;
        for (vma = mm->mmap; vma; vma = vma->vm_next) {
                cond_resched();
@@ -869,17 +865,15 @@ static int userfaultfd_release(struct inode *inode, struct file *file)
                        continue;
                }
                new_flags = vma->vm_flags & ~(VM_UFFD_MISSING | VM_UFFD_WP);
-               if (still_valid) {
-                       prev = vma_merge(mm, prev, vma->vm_start, vma->vm_end,
-                                        new_flags, vma->anon_vma,
-                                        vma->vm_file, vma->vm_pgoff,
-                                        vma_policy(vma),
-                                        NULL_VM_UFFD_CTX);
-                       if (prev)
-                               vma = prev;
-                       else
-                               prev = vma;
-               }
+               prev = vma_merge(mm, prev, vma->vm_start, vma->vm_end,
+                                new_flags, vma->anon_vma,
+                                vma->vm_file, vma->vm_pgoff,
+                                vma_policy(vma),
+                                NULL_VM_UFFD_CTX);
+               if (prev)
+                       vma = prev;
+               else
+                       prev = vma;
                vma->vm_flags = new_flags;
                vma->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX;
        }
@@ -1309,8 +1303,6 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx,
                goto out;
 
        mmap_write_lock(mm);
-       if (!mmget_still_valid(mm))
-               goto out_unlock;
        vma = find_vma_prev(mm, start, &prev);
        if (!vma)
                goto out_unlock;
@@ -1511,8 +1503,6 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx,
                goto out;
 
        mmap_write_lock(mm);
-       if (!mmget_still_valid(mm))
-               goto out_unlock;
        vma = find_vma_prev(mm, start, &prev);
        if (!vma)
                goto out_unlock;