[PATCH AUTOSEL 4.9 02/13] MIPS: tlbex: Explicitly cast _PAGE_NO_EXEC to a boolean

From: Sasha Levin
Date: Sun Sep 29 2019 - 13:38:09 EST


From: Nathan Chancellor <natechancellor@xxxxxxxxx>

[ Upstream commit c59ae0a1055127dd3828a88e111a0db59b254104 ]

clang warns:

arch/mips/mm/tlbex.c:634:19: error: use of logical '&&' with constant
operand [-Werror,-Wconstant-logical-operand]
if (cpu_has_rixi && _PAGE_NO_EXEC) {
^ ~~~~~~~~~~~~~
arch/mips/mm/tlbex.c:634:19: note: use '&' for a bitwise operation
if (cpu_has_rixi && _PAGE_NO_EXEC) {
^~
&
arch/mips/mm/tlbex.c:634:19: note: remove constant to silence this
warning
if (cpu_has_rixi && _PAGE_NO_EXEC) {
~^~~~~~~~~~~~~~~~
1 error generated.

Explicitly cast this value to a boolean so that clang understands we
intend for this to be a non-zero value.

Fixes: 00bf1c691d08 ("MIPS: tlbex: Avoid placing software PTE bits in Entry* PFN fields")
Link: https://github.com/ClangBuiltLinux/linux/issues/609
Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
Signed-off-by: Paul Burton <paul.burton@xxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: James Hogan <jhogan@xxxxxxxxxx>
Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: clang-built-linux@xxxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/mips/mm/tlbex.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 3cc5b2e4263c0..47d50197789be 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -637,7 +637,7 @@ static __maybe_unused void build_convert_pte_to_entrylo(u32 **p,
return;
}

- if (cpu_has_rixi && _PAGE_NO_EXEC) {
+ if (cpu_has_rixi && !!_PAGE_NO_EXEC) {
if (fill_includes_sw_bits) {
UASM_i_ROTR(p, reg, reg, ilog2(_PAGE_GLOBAL));
} else {
--
2.20.1