Patch "s390/mm: don't drop errors in get_guest_storage_key" has been added to the 4.7-stable tree

This is a note to let you know that I've just added the patch titled

s390/mm: don't drop errors in get_guest_storage_key

to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
s390-mm-don-t-drop-errors-in-get_guest_storage_key.patch
and it can be found in the queue-4.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: David Hildenbrand <[email protected]>
Date: Tue, 10 May 2016 13:51:54 +0200
Subject: s390/mm: don't drop errors in get_guest_storage_key

From: David Hildenbrand <[email protected]>

commit c427c42cd612719e8fb8b5891cc9761e7770024e upstream.

Commit 1e133ab296f3 ("s390/mm: split arch/s390/mm/pgtable.c") changed the return value of get_guest_storage_key to an unsigned char, resulting in -EFAULT getting interpreted as a valid storage key.

---
 arch/s390/include/asm/pgtable.h |    2 +-
 arch/s390/mm/pgtable.c          |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

@@ -893,7 +893,7 @@ void ptep_zap_key(struct mm_struct *mm,
 bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long address);
 int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
 			  unsigned char key, bool nq);
-unsigned char get_guest_storage_key(struct mm_struct *mm, unsigned long addr);
+unsigned long get_guest_storage_key(struct mm_struct *mm, unsigned long addr);
 
 /*
  * Certain architectures need to do special things when PTEs

@@ -543,7 +543,7 @@ int set_guest_storage_key(struct mm_stru
 }
 EXPORT_SYMBOL(set_guest_storage_key);
 
-unsigned char get_guest_storage_key(struct mm_struct *mm, unsigned long addr)
+unsigned long get_guest_storage_key(struct mm_struct *mm, unsigned long addr)
 {
 	unsigned char key;
 	spinlock_t *ptl;

Patches currently in stable-queue which might be from [email protected] are

queue-4.7/s390-mm-don-t-drop-errors-in-get_guest_storage_key.patch queue-4.7/s390-mm-fix-gmap-tlb-flush-issues.patch