From: Russell King rmk+kernel@armlinux.org.uk
commit 39d3454c3513840eb123b3913fda6903e45ce671 upstream.
Building with gcc 4.9.2 reveals a latent bug in the PCI accessors for Footbridge platforms, which causes a fatal alignment fault while accessing IO memory. Fix this by making the assembly volatile.
Cc: stable@vger.kernel.org Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm/mach-footbridge/dc21285.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
--- a/arch/arm/mach-footbridge/dc21285.c +++ b/arch/arm/mach-footbridge/dc21285.c @@ -65,15 +65,15 @@ dc21285_read_config(struct pci_bus *bus, if (addr) switch (size) { case 1: - asm("ldrb %0, [%1, %2]" + asm volatile("ldrb %0, [%1, %2]" : "=r" (v) : "r" (addr), "r" (where) : "cc"); break; case 2: - asm("ldrh %0, [%1, %2]" + asm volatile("ldrh %0, [%1, %2]" : "=r" (v) : "r" (addr), "r" (where) : "cc"); break; case 4: - asm("ldr %0, [%1, %2]" + asm volatile("ldr %0, [%1, %2]" : "=r" (v) : "r" (addr), "r" (where) : "cc"); break; } @@ -99,17 +99,17 @@ dc21285_write_config(struct pci_bus *bus if (addr) switch (size) { case 1: - asm("strb %0, [%1, %2]" + asm volatile("strb %0, [%1, %2]" : : "r" (value), "r" (addr), "r" (where) : "cc"); break; case 2: - asm("strh %0, [%1, %2]" + asm volatile("strh %0, [%1, %2]" : : "r" (value), "r" (addr), "r" (where) : "cc"); break; case 4: - asm("str %0, [%1, %2]" + asm volatile("str %0, [%1, %2]" : : "r" (value), "r" (addr), "r" (where) : "cc"); break;