[linux-kernel] Update patches for v5

contrib/linux-kernel/lib/zstd/zstd_internal.h

@@ -134,8 +134,21 @@ ZSTD_STATIC void ZSTD_copy8(void *dst, const void *src) {
 #define WILDCOPY_OVERLENGTH 8
 ZSTD_STATIC void ZSTD_wildcopy(void *dst, const void *src, ptrdiff_t length)
 {
-	if (length > 0)
-		memcpy(dst, src, length);
+	const BYTE* ip = (const BYTE*)src;
+	BYTE* op = (BYTE*)dst;
+	BYTE* const oend = op + length;
+	/* Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388.
+	 * Avoid the bad case where the loop only runs once by handling the
+	 * special case separately. This doesn't trigger the bug because it
+	 * doesn't involve pointer/integer overflow.
+	 */
+	if (length <= 8)
+		return ZSTD_copy8(dst, src);
+	do {
+		ZSTD_copy8(op, ip);
+		op += 8;
+		ip += 8;
+	} while (op < oend);
 }
 
 /*-*******************************************