[PATCH 1/2] ARM: copypage-fa: add kto and kfrom to input operands list

From: Stefan Agner
Date: Mon Oct 15 2018 - 18:16:43 EST


When functions incoming parameters are not in input operands list gcc
4.5 does not load the parameters into registers before calling this
function but the inline assembly assumes valid addresses inside this
function. This breaks the code because r0 and r1 are invalid when
execution enters v4wb_copy_user_page ()

Also the constant needs to be used as third input operand so account
for that as well.

This fixes copypage-fa.c what has previously done before for the other
copypage implementations in commit 9a40ac86152c ("ARM: 6164/1: Add kto
and kfrom to input operands list.").

Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
---
arch/arm/mm/copypage-fa.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mm/copypage-fa.c b/arch/arm/mm/copypage-fa.c
index d130a5ece5d5..ec6501308c60 100644
--- a/arch/arm/mm/copypage-fa.c
+++ b/arch/arm/mm/copypage-fa.c
@@ -22,7 +22,7 @@ fa_copy_user_page(void *kto, const void *kfrom)
{
asm("\
stmfd sp!, {r4, lr} @ 2\n\
- mov r2, %0 @ 1\n\
+ mov r2, %2 @ 1\n\
1: ldmia r1!, {r3, r4, ip, lr} @ 4\n\
stmia r0, {r3, r4, ip, lr} @ 4\n\
mcr p15, 0, r0, c7, c14, 1 @ 1 clean and invalidate D line\n\
@@ -36,7 +36,7 @@ fa_copy_user_page(void *kto, const void *kfrom)
mcr p15, 0, r2, c7, c10, 4 @ 1 drain WB\n\
ldmfd sp!, {r4, pc} @ 3"
:
- : "I" (PAGE_SIZE / 32));
+ : "r" (kto), "r" (kfrom), "I" (PAGE_SIZE / 32));
}

void fa_copy_user_highpage(struct page *to, struct page *from,
--
2.19.1