s390: pci: don't print uninitialized data for debugging

gcc correctly warns about an incorrect use of the 'pa' variable in case
we pass an empty scatterlist to __s390_dma_map_sg:

  arch/s390/pci/pci_dma.c: In function '__s390_dma_map_sg':
  arch/s390/pci/pci_dma.c:309:13: warning: 'pa' may be used uninitialized in this function [-Wmaybe-uninitialized]

This adds a bogus initialization to the function to sanitize the debug
output.  I would have preferred a solution without the initialization,
but I only got the report from the kbuild bot after turning on the
warning again, and didn't manage to reproduce it myself.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Arnd Bergmann 2016-11-10 17:44:48 +01:00 committed by Linus Torvalds
parent 069013a9e2
commit 92dfffee97

View File

@ -423,7 +423,7 @@ static int __s390_dma_map_sg(struct device *dev, struct scatterlist *sg,
dma_addr_t dma_addr_base, dma_addr;
int flags = ZPCI_PTE_VALID;
struct scatterlist *s;
unsigned long pa;
unsigned long pa = 0;
int ret;
size = PAGE_ALIGN(size);