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	"Wilcox, Matthew R" <matthew.r.wilcox@intel.com>,
	"ross.zwisler@linux.intel.com" <ross.zwisler@linux.intel.com>
From: Jared Hulbert <jaredeh@gmail.com>
Subject: DAX: bug in COW no page fault?
Message-ID: <56ABDBC7.5030703@gmail.com>
Date: Fri, 29 Jan 2016 13:38:15 -0800
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Why isn't this required?

diff --git a/fs/dax.c b/fs/dax.c
index a7f77e1..30f2abe 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -416,6 +416,7 @@ int __dax_fault(struct vm_area_struct *vma, struct vm_fault
                                error = -EIO;
                                goto out;
                        }
+                       i_mmap_unlock_read(mapping);
                }
                return VM_FAULT_LOCKED;
        }