The patch titled
Subject: mm: call flush_dcache_page() in memcpy_to_page() and memzero_page()
has been added to the -mm tree. Its filename is
mm-call-flush_dcache_page-in-memcpy_to_page-and-memzero_page.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-call-flush_dcache_page-in-memcpy_to_page-and-memzero_page.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-call-flush_dcache_page-in-memcpy_to_page-and-memzero_page.patch
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------------------------------------------------------
From: Christoph Hellwig <hch@xxxxxx>
Subject: mm: call flush_dcache_page() in memcpy_to_page() and memzero_page()
memcpy_to_page and memzero_page can write to arbitrary pages, which could
be in the page cache or in high memory, so call flush_kernel_dcache_pages
to flush the dcache.
Link: https://lkml.kernel.org/r/20210713055231.137602-2-hch@xxxxxx
Fixes: bb90d4bc7b6a ("mm/highmem: Lift memcpy_[to|from]_page to core")
Fixes: 28961998f858 ("iov_iter: lift memzero_page() to highmem.h")
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
Cc: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/highmem.h | 2 ++
1 file changed, 2 insertions(+)
--- a/include/linux/highmem.h~mm-call-flush_dcache_page-in-memcpy_to_page-and-memzero_page
+++ a/include/linux/highmem.h
@@ -318,6 +318,7 @@ static inline void memcpy_to_page(struct
VM_BUG_ON(offset + len > PAGE_SIZE);
memcpy(to + offset, from, len);
+ flush_dcache_page(page);
kunmap_local(to);
}
@@ -325,6 +326,7 @@ static inline void memzero_page(struct p
{
char *addr = kmap_atomic(page);
memset(addr + offset, 0, len);
+ flush_dcache_page(page);
kunmap_atomic(addr);
}
_
Patches currently in -mm which might be from hch@xxxxxx are
mm-fix-the-try_to_unmap-prototype-for-config_mmu.patch
mm-call-flush_dcache_page-in-memcpy_to_page-and-memzero_page.patch
mm-use-kmap_local_page-in-memzero_page.patch
