[PATCH 02/23] arm64: allow pte_offset_map() to fail

Hugh Dickins
2023-05-10T04:44:02Z

In rare transient cases, not yet made possible, pte_offset_map() and
pte_offset_map_lock() may not find a page table: handle appropriately.

Signed-off-by: Hugh Dickins <hughd@google.com>
---
arch/arm64/mm/fault.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 9e0db5c387e3..a58780d5fac4 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -177,6 +177,9 @@ static void show_pte(unsigned long addr)
break;

ptep = pte_offset_map(pmdp, addr);
+ if (!ptep)
+ break;
+
pte = READ_ONCE(*ptep);
pr_cont(", pte=%016llx", pte_val(pte));
pte_unmap(ptep);
--
2.35.3