s390/pci: add extra padding to function measurement block

[ Upstream commit 9d89d9e61d361f3adb75e1aebe4bb367faf16cfa ]

Newer machines might use a different (larger) format for function
measurement blocks. To ensure that we comply with the alignment
requirement on these machines and prevent memory corruption (when
firmware writes more data than we expect) add 16 padding bytes
at the end of the fmb.

Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h
index 4e33fe3..5b7153b 100644 (file)
--- a/arch/s390/include/asm/pci.h
+++ b/arch/s390/include/asm/pci.h
@@ -45,7 +45,8 @@ struct zpci_fmb {
        u64 rpcit_ops;
        u64 dma_rbytes;
        u64 dma_wbytes;
-} __packed __aligned(64);
+       u64 pad[2];
+} __packed __aligned(128);
 
 enum zpci_state {
        ZPCI_FN_STATE_RESERVED,