From 8bd3ff1d04183848b589c53e94e4467a83746c8f Mon Sep 17 00:00:00 2001 From: Dmitriy Monakhov Date: Tue, 7 Nov 2006 15:40:54 +0100 Subject: [PATCH] from mm/memory.c: 1434 static inline void cow_user_page(struct page *dst, struct page *src, unsigned long va) 1435 { 1436 /* 1437 * If the source page was a PFN mapping, we don't have 1438 * a "struct page" for it. We do a best-effort copy by 1439 * just copying from the original user address. If that 1440 * fails, we just zero-fill it. Live with it. 1441 */ 1442 if (unlikely(!src)) { 1443 void *kaddr = kmap_atomic(dst, KM_USER0); 1444 void __user *uaddr = (void __user *)(va & PAGE_MASK); 1445 1446 /* 1447 * This really shouldn't fail, because the page is there 1448 * in the page tables. But it might just be unreadable, 1449 * in which case we just give up and fill the result with 1450 * zeroes. 1451 */ 1452 if (__copy_from_user_inatomic(kaddr, uaddr, PAGE_SIZE)) 1453 memset(kaddr, 0, PAGE_SIZE); 1454 kunmap_atomic(kaddr, KM_USER0); #### D-cache have to be flushed here. #### It seems it is just forgotten. 1455 return; 1456 1457 } 1458 copy_user_highpage(dst, src, va); #### Ok here. flush_dcache_page() called from this func if arch need it 1459 } Signed-off-by: Dmitriy Monakhov Acked-by: David Miller Signed-off-by: Adrian Bunk --- mm/memory.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/memory.c b/mm/memory.c index 85e80a57db29..a4caa2f223e1 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1418,6 +1418,7 @@ static inline void cow_user_page(struct page *dst, struct page *src, unsigned lo if (__copy_from_user_inatomic(kaddr, uaddr, PAGE_SIZE)) memset(kaddr, 0, PAGE_SIZE); kunmap_atomic(kaddr, KM_USER0); + flush_dcache_page(dst); return; } -- 2.39.5