Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fixes from Martin Schwidefsky:
"Another two bug fixes:

- ptrace partial write information leak

- a guest page hinting regression introduced with v4.6"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/mm: Fix cmma unused transfer from pgste into pte
s390/ptrace: Preserve previous registers for short regset write

arch/s390/kernel/ptrace.c

···
 	if (target == current)
 		save_fpu_regs();
 
+	if (MACHINE_HAS_VX)
+		convert_vx_to_fp(fprs, target->thread.fpu.vxrs);
+	else
+		memcpy(&fprs, target->thread.fpu.fprs, sizeof(fprs));
+
 	/* If setting FPC, must validate it first. */
 	if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
 		u32 ufpc[2] = { target->thread.fpu.fpc, 0 };
···
 		return -ENODEV;
 	if (target == current)
 		save_fpu_regs();
+
+	for (i = 0; i < __NUM_VXRS_LOW; i++)
+		vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
 
 	rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
 	if (rc == 0)

arch/s390/mm/pgtable.c

···
 	return pgste;
 }
 
-static inline void ptep_xchg_commit(struct mm_struct *mm,
+static inline pte_t ptep_xchg_commit(struct mm_struct *mm,
 				    unsigned long addr, pte_t *ptep,
 				    pgste_t pgste, pte_t old, pte_t new)
 {
···
 	} else {
 		*ptep = new;
 	}
+	return old;
 }
 
 pte_t ptep_xchg_direct(struct mm_struct *mm, unsigned long addr,
···
 	preempt_disable();
 	pgste = ptep_xchg_start(mm, addr, ptep);
 	old = ptep_flush_direct(mm, addr, ptep);
-	ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
+	old = ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
 	preempt_enable();
 	return old;
 }
···
 	preempt_disable();
 	pgste = ptep_xchg_start(mm, addr, ptep);
 	old = ptep_flush_lazy(mm, addr, ptep);
-	ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
+	old = ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
 	preempt_enable();
 	return old;
 }