[PATCH 4.15 107/122] ARM: orion: fix orion_ge00_switch_board_info initialization

From: Greg Kroah-Hartman
Date: Wed Mar 07 2018 - 15:21:25 EST


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

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

From: Arnd Bergmann <arnd@xxxxxxxx>

commit 8337d083507b9827dfb36d545538b7789df834fd upstream.

A section type mismatch warning shows up when building with LTO,
since orion_ge00_mvmdio_bus_name was put in __initconst but not marked
const itself:

include/linux/of.h: In function 'spear_setup_of_timer':
arch/arm/mach-spear/time.c:207:34: error: 'timer_of_match' causes a section type conflict with 'orion_ge00_mvmdio_bus_name'
static const struct of_device_id timer_of_match[] __initconst = {
^
arch/arm/plat-orion/common.c:475:32: note: 'orion_ge00_mvmdio_bus_name' was declared here
static __initconst const char *orion_ge00_mvmdio_bus_name = "orion-mii";
^

As pointed out by Andrew Lunn, it should in fact be 'const' but not
'__initconst' because the string is never copied but may be accessed
after the init sections are freed. To fix that, I get rid of the
extra symbol and rewrite the initialization in a simpler way that
assigns both the bus_id and modalias statically.

I spotted another theoretical bug in the same place, where d->netdev[i]
may be an out of bounds access, this can be fixed by moving the device
assignment into the loop.

Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/arm/plat-orion/common.c | 23 +++++++++++------------
1 file changed, 11 insertions(+), 12 deletions(-)

--- a/arch/arm/plat-orion/common.c
+++ b/arch/arm/plat-orion/common.c
@@ -472,28 +472,27 @@ void __init orion_ge11_init(struct mv643
/*****************************************************************************
* Ethernet switch
****************************************************************************/
-static __initconst const char *orion_ge00_mvmdio_bus_name = "orion-mii";
-static __initdata struct mdio_board_info
- orion_ge00_switch_board_info;
+static __initdata struct mdio_board_info orion_ge00_switch_board_info = {
+ .bus_id = "orion-mii",
+ .modalias = "mv88e6085",
+};

void __init orion_ge00_switch_init(struct dsa_chip_data *d)
{
- struct mdio_board_info *bd;
unsigned int i;

if (!IS_BUILTIN(CONFIG_PHYLIB))
return;

- for (i = 0; i < ARRAY_SIZE(d->port_names); i++)
- if (!strcmp(d->port_names[i], "cpu"))
+ for (i = 0; i < ARRAY_SIZE(d->port_names); i++) {
+ if (!strcmp(d->port_names[i], "cpu")) {
+ d->netdev[i] = &orion_ge00.dev;
break;
+ }
+ }

- bd = &orion_ge00_switch_board_info;
- bd->bus_id = orion_ge00_mvmdio_bus_name;
- bd->mdio_addr = d->sw_addr;
- d->netdev[i] = &orion_ge00.dev;
- strcpy(bd->modalias, "mv88e6085");
- bd->platform_data = d;
+ orion_ge00_switch_board_info.mdio_addr = d->sw_addr;
+ orion_ge00_switch_board_info.platform_data = d;

mdiobus_register_board_info(&orion_ge00_switch_board_info, 1);
}