[PATCH 4.8 069/138] KVM: s390: Fix STHYI buffer alignment for diag224

[Greg Kroah-Hartman]

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

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

From: Janosch Frank <frankja@xxxxxxxxxxxxxxxxxx>

commit 45c7ee43a5184ddbff652ee0d2e826f86f1b616b upstream.

Diag224 requires a page-aligned 4k buffer to store the name table
into. kmalloc does not guarantee page alignment, hence we replace it
with __get_free_page for the buffer allocation.

Reported-by: Michael Holzheu <holzheu@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx>
Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/s390/kvm/sthyi.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/s390/kvm/sthyi.c
+++ b/arch/s390/kvm/sthyi.c
@@ -315,7 +315,7 @@ static void fill_diag(struct sthyi_sctns
 	if (r < 0)
 		goto out;
 
-	diag224_buf = kmalloc(PAGE_SIZE, GFP_KERNEL | GFP_DMA);
+	diag224_buf = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
 	if (!diag224_buf || diag224(diag224_buf))
 		goto out;
 
@@ -378,7 +378,7 @@ static void fill_diag(struct sthyi_sctns
 	sctns->par.infpval1 |= PAR_WGHT_VLD;
 
 out:
-	kfree(diag224_buf);
+	free_page((unsigned long)diag224_buf);
 	vfree(diag204_buf);
 }