[PATCH 5.12 680/700] csky: syscache: Fixup duplicate cache flush

From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 04:15:38 EST


From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>

[ Upstream commit 6ea42c84f33368eb3fe1ec1bff8d7cb1a5c7b07a ]

The current csky logic of sys_cacheflush is wrong, it'll cause
icache flush call dcache flush again. Now fixup it with a
conditional "break & fallthrough".

Fixes: 997153b9a75c ("csky: Add flush_icache_mm to defer flush icache all")
Fixes: 0679d29d3e23 ("csky: fix syscache.c fallthrough warning")
Acked-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Co-Developed-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/csky/mm/syscache.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/arch/csky/mm/syscache.c b/arch/csky/mm/syscache.c
index 4e51d63850c4..cd847ad62c7e 100644
--- a/arch/csky/mm/syscache.c
+++ b/arch/csky/mm/syscache.c
@@ -12,15 +12,17 @@ SYSCALL_DEFINE3(cacheflush,
int, cache)
{
switch (cache) {
- case ICACHE:
case BCACHE:
- flush_icache_mm_range(current->mm,
- (unsigned long)addr,
- (unsigned long)addr + bytes);
- fallthrough;
case DCACHE:
dcache_wb_range((unsigned long)addr,
(unsigned long)addr + bytes);
+ if (cache != BCACHE)
+ break;
+ fallthrough;
+ case ICACHE:
+ flush_icache_mm_range(current->mm,
+ (unsigned long)addr,
+ (unsigned long)addr + bytes);
break;
default:
return -EINVAL;
--
2.30.2