From 1f983499b6c6cf7f3afea2655100d95ef6ef118a Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 19 Feb 2021 16:41:07 +0800 Subject: [PATCH] ARM: footbridge: fix dc21285 PCI configuration accessors stable inclusion from stable-5.10.15 commit 384cddbee46f07b029c7b44622d504e6ec4b3e22 bugzilla: 48167 -------------------------------- 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 Signed-off-by: Greg Kroah-Hartman Signed-off-by: Zheng Zengkai Acked-by: Xie XiuQi --- arch/arm/mach-footbridge/dc21285.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/arm/mach-footbridge/dc21285.c b/arch/arm/mach-footbridge/dc21285.c index 416462e3f5d6..f9713dc561cf 100644 --- 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, unsigned int devfn, int where, 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, unsigned int devfn, int where, 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; -- GitLab