[PATCH v2 09/11] nds32/tlb: Fix __p*_free_tlb()

From: Peter Zijlstra
Date: Fri Jul 17 2020 - 07:15:08 EST


Just like regular pages, page directories need to observe the
following order:

1) unhook
2) TLB invalidate
3) free

to ensure it is safe against concurrent accesses.

Even though NDS32 is UP only, we still need to observe this order
because mmu_gather is preemptible.

NDS32 does not in fact have PMDs.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/nds32/include/asm/tlb.h | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

--- a/arch/nds32/include/asm/tlb.h
+++ b/arch/nds32/include/asm/tlb.h
@@ -6,6 +6,11 @@

#include <asm-generic/tlb.h>

-#define __pte_free_tlb(tlb, pte, addr) pte_free((tlb)->mm, pte)
+#define __pte_free_tlb(tlb, pte, address) \
+do { \
+ pgtable_pte_page_dtor(pte); \
+ tlb_remove_table((tlb), (pte)); \
+} while (0)
+

#endif