alloc_tag: mark pages reserved during CMA activation as not tagged

During CMA activation, pages in CMA area are prepared and then freed
without being allocated.  This triggers warnings when memory allocation
debug config (CONFIG_MEM_ALLOC_PROFILING_DEBUG) is enabled.  Fix this by
marking these pages not tagged before freeing them.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: d224eb0 ("codetag: debug: mark codetags for reserved pages as empty")
Signed-off-by: Suren Baghdasaryan <[email protected]>
Acked-by: David Hildenbrand <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Pasha Tatashin <[email protected]>
Cc: Sourav Panda <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: <[email protected]>	[6.10]
Signed-off-by: Andrew Morton <[email protected]>

Author: surenbaghdasaryan

mm/mm_init.c

@@ -2244,6 +2244,8 @@ void __init init_cma_reserved_pageblock(struct page *page)
 
 	set_pageblock_migratetype(page, MIGRATE_CMA);
 	set_page_refcounted(page);
+	/* pages were reserved and not allocated */
+	clear_page_tag_ref(page);
 	__free_pages(page, pageblock_order);
 
 	adjust_managed_page_count(page, pageblock_nr_pages);