+ highmem-fix-a-memory-copy-problem-in-memcpy_from_folio.patch added to mm-hotfixes-unstable branch

+ highmem-fix-a-memory-copy-problem-in-memcpy_from_folio.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: highmem: fix a memory copy problem in memcpy_from_folio
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     highmem-fix-a-memory-copy-problem-in-memcpy_from_folio.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/highmem-fix-a-memory-copy-problem-in-memcpy_from_folio.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Su Hui <suhui@nfschina.com>
Subject: highmem: fix a memory copy problem in memcpy_from_folio
Date: Thu, 30 Nov 2023 11:40:18 +0800

Clang static checker complains that value stored to 'from' is never read. 
And memcpy_from_folio() only copy the last chunk memory from folio to
destination.  Use 'to += chunk' to replace 'from += chunk' to fix this
typo problem.

Link: https://lkml.kernel.org/r/20231130034017.1210429-1-suhui@nfschina.com
Fixes: b23d03ef7af5 ("highmem: add memcpy_to_folio() and memcpy_from_folio()")
Signed-off-by: Su Hui <suhui@nfschina.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jiaqi Yan <jiaqiyan@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Tom Rix <trix@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/highmem.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/include/linux/highmem.h~highmem-fix-a-memory-copy-problem-in-memcpy_from_folio
+++ a/include/linux/highmem.h
@@ -454,7 +454,7 @@ static inline void memcpy_from_folio(cha
 		memcpy(to, from, chunk);
 		kunmap_local(from);
 
-		from += chunk;
+		to += chunk;
 		offset += chunk;
 		len -= chunk;
 	} while (len > 0);
_

Patches currently in -mm which might be from suhui@nfschina.com are

highmem-fix-a-memory-copy-problem-in-memcpy_from_folio.patch