[PATCH 3/3] nds32: Disable local irq before calling cpu_dcache_wb_page in copy_user_highpage

From: Vincent Chen
Date: Tue May 15 2018 - 04:58:40 EST


In order to ensure that all data in source page has been written back
to memory before copy_page, the local irq shall be disabled before
calling cpu_dcache_wb_page(). In addition, removing unneeded page
invalidation for 'to' page.

Signed-off-by: Vincent Chen <vincentc@xxxxxxxxxxxxx>
---
arch/nds32/mm/cacheflush.c | 4 +---
1 files changed, 1 insertions(+), 3 deletions(-)

diff --git a/arch/nds32/mm/cacheflush.c b/arch/nds32/mm/cacheflush.c
index acfdb45..c97caaf 100644
--- a/arch/nds32/mm/cacheflush.c
+++ b/arch/nds32/mm/cacheflush.c
@@ -156,11 +156,9 @@ void copy_user_highpage(struct page *to, struct page *from,
pto = page_to_phys(to);
pfrom = page_to_phys(from);

+ local_irq_save(flags);
if (aliasing(vaddr, (unsigned long)kfrom))
cpu_dcache_wb_page((unsigned long)kfrom);
- if (aliasing(vaddr, (unsigned long)kto))
- cpu_dcache_inval_page((unsigned long)kto);
- local_irq_save(flags);
vto = kremap0(vaddr, pto);
vfrom = kremap1(vaddr, pfrom);
copy_page((void *)vto, (void *)vfrom);
--
1.7.1