From: Arnd Bergmann <arnd@xxxxxxxx>
This patch has been added to the 4.1 stable tree. If you have any
objections, please let us know.
===============
[ Upstream commit e70dda0868fad0f74c46df21f7f45fec24f29879 ]
pci_read_config_word() might fail and not initialize its output,
as pointed out by older versions of gcc when using the -Wmaybe-unintialized
flag:
drivers/mtd/maps/ichxrom.c: In function ‘ichxrom_cleanup’:
drivers/mtd/maps/ichxrom.c:63:2: error: ‘word’ is used uninitialized in this function [-Werror=uninitialized]
This is apparently a correct warning, though it does not show up
with newer compilers. Changing the code to not attempt to write
back uninitialized data into PCI config space is a correct
fix for the problem and avoids the warning.
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Reviewed-by: Marek Vasut <marex@xxxxxxx>
Signed-off-by: Brian Norris <computersforpeace@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/mtd/maps/ichxrom.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/mtd/maps/ichxrom.c b/drivers/mtd/maps/ichxrom.c
index c7478e18f485..2fb2d0ec3367 100644
--- a/drivers/mtd/maps/ichxrom.c
+++ b/drivers/mtd/maps/ichxrom.c
@@ -57,10 +57,12 @@ static void ichxrom_cleanup(struct ichxrom_window *window)
{
struct ichxrom_map_info *map, *scratch;
u16 word;
+ int ret;
/* Disable writes through the rom window */
- pci_read_config_word(window->pdev, BIOS_CNTL, &word);
- pci_write_config_word(window->pdev, BIOS_CNTL, word & ~1);
+ ret = pci_read_config_word(window->pdev, BIOS_CNTL, &word);
+ if (!ret)
+ pci_write_config_word(window->pdev, BIOS_CNTL, word & ~1);
pci_dev_put(window->pdev);
/* Free all of the mtd devices */
--
2.14.1