s390/pci: enforce fmb page boundary rule
The function measurement block must not cross a page boundary. Ensure
that by raising the alignment requirement to the smallest power of 2
larger than the size of the fmb.
Fixes: d0b088531 ("s390/pci: performance statistics and debug infrastructure")
Cc: stable@vger.kernel.org # v3.8+
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h
index dc763ea..f833082d 100644
--- a/arch/s390/include/asm/pci.h
+++ b/arch/s390/include/asm/pci.h
@@ -45,7 +45,7 @@
u64 rpcit_ops;
u64 dma_rbytes;
u64 dma_wbytes;
-} __packed __aligned(16);
+} __packed __aligned(64);
enum zpci_state {
ZPCI_FN_STATE_RESERVED,
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index f76d01e..9fd59a7 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -860,8 +860,11 @@
static int zpci_mem_init(void)
{
+ BUILD_BUG_ON(!is_power_of_2(__alignof__(struct zpci_fmb)) ||
+ __alignof__(struct zpci_fmb) < sizeof(struct zpci_fmb));
+
zdev_fmb_cache = kmem_cache_create("PCI_FMB_cache", sizeof(struct zpci_fmb),
- 16, 0, NULL);
+ __alignof__(struct zpci_fmb), 0, NULL);
if (!zdev_fmb_cache)
goto error_fmb;