diff mbox series

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

Message ID e72f6f3e-a8d4-3ed-2b4-5d3ced41484@google.com (mailing list archive)
State Awaiting Upstream
Headers show
Series arch: allow pte_offset_map[_lock]() to fail | expand

Commit Message

Hugh Dickins May 10, 2023, 4:43 a.m. UTC 
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(+)

Comments

Catalin Marinas May 25, 2023, 4:37 p.m. UTC | #1 
On Tue, May 09, 2023 at 09:43:47PM -0700, Hugh Dickins wrote:
> 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>

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
diff mbox series

Patch

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);