4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Peter Zijlstra <[email protected]>

commit 0b3589be9b98994ce3d5aeca52445d1f5627c4ba upstream.

Andres reported that MMAP2 records for anonymous memory always have
their protection field 0.

Turns out, someone daft put the prot/flags generation code in the file
branch, leaving them unset for anonymous memory.

Reported-by: Andres Freund <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Don Zickus <[email protected]
Cc: Jiri Olsa <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Fixes: f972eb63b100 ("perf: Pass protection and flags bits through mmap2 
interface")
Link: 
http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 kernel/events/core.c |   42 +++++++++++++++++++++---------------------
 1 file changed, 21 insertions(+), 21 deletions(-)

--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -6606,6 +6606,27 @@ static void perf_event_mmap_event(struct
        char *buf = NULL;
        char *name;
 
+       if (vma->vm_flags & VM_READ)
+               prot |= PROT_READ;
+       if (vma->vm_flags & VM_WRITE)
+               prot |= PROT_WRITE;
+       if (vma->vm_flags & VM_EXEC)
+               prot |= PROT_EXEC;
+
+       if (vma->vm_flags & VM_MAYSHARE)
+               flags = MAP_SHARED;
+       else
+               flags = MAP_PRIVATE;
+
+       if (vma->vm_flags & VM_DENYWRITE)
+               flags |= MAP_DENYWRITE;
+       if (vma->vm_flags & VM_MAYEXEC)
+               flags |= MAP_EXECUTABLE;
+       if (vma->vm_flags & VM_LOCKED)
+               flags |= MAP_LOCKED;
+       if (vma->vm_flags & VM_HUGETLB)
+               flags |= MAP_HUGETLB;
+
        if (file) {
                struct inode *inode;
                dev_t dev;
@@ -6632,27 +6653,6 @@ static void perf_event_mmap_event(struct
                maj = MAJOR(dev);
                min = MINOR(dev);
 
-               if (vma->vm_flags & VM_READ)
-                       prot |= PROT_READ;
-               if (vma->vm_flags & VM_WRITE)
-                       prot |= PROT_WRITE;
-               if (vma->vm_flags & VM_EXEC)
-                       prot |= PROT_EXEC;
-
-               if (vma->vm_flags & VM_MAYSHARE)
-                       flags = MAP_SHARED;
-               else
-                       flags = MAP_PRIVATE;
-
-               if (vma->vm_flags & VM_DENYWRITE)
-                       flags |= MAP_DENYWRITE;
-               if (vma->vm_flags & VM_MAYEXEC)
-                       flags |= MAP_EXECUTABLE;
-               if (vma->vm_flags & VM_LOCKED)
-                       flags |= MAP_LOCKED;
-               if (vma->vm_flags & VM_HUGETLB)
-                       flags |= MAP_HUGETLB;
-
                goto got_name;
        } else {
                if (vma->vm_ops && vma->vm_ops->name) {


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