Merge branch 'linus' into x86/mm, to refresh the branch and pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 9 insertions, 8 deletions

diff --git a/mm/sparse.c b/mm/sparse.c
index 77d91e565045..338cf946dee8 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -792,6 +792,13 @@ static void section_deactivate(unsigned long pfn, unsigned long nr_pages,
 		unsigned long section_nr = pfn_to_section_nr(pfn);
 
 		/*
+		 * Mark the section invalid so that valid_section()
+		 * return false. This prevents code from dereferencing
+		 * ms->usage array.
+		 */
+		ms->section_mem_map &= ~SECTION_HAS_MEM_MAP;
+
+		/*
 		 * When removing an early section, the usage map is kept (as the
 		 * usage maps of other sections fall into the same page). It
 		 * will be re-used when re-adding the section - which is then no
@@ -799,16 +806,10 @@ static void section_deactivate(unsigned long pfn, unsigned long nr_pages,
 		 * was allocated during boot.
 		 */
 		if (!PageReserved(virt_to_page(ms->usage))) {
-			kfree(ms->usage);
-			ms->usage = NULL;
+			kfree_rcu(ms->usage, rcu);
+			WRITE_ONCE(ms->usage, NULL);
 		}
 		memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
-		/*
-		 * Mark the section invalid so that valid_section()
-		 * return false. This prevents code from dereferencing
-		 * ms->usage array.
-		 */
-		ms->section_mem_map &= ~SECTION_HAS_MEM_MAP;
 	}
 
 	/*