From 63f8896919fdfd2d0686bc7d7ffb74620f295415 Mon Sep 17 00:00:00 2001
From: mpi <mpi@openbsd.org>
Date: Thu, 30 May 2024 10:56:24 +0000
Subject: [PATCH] Ensure pmap_create() waits in case kernel virtual space
 shortage.

Prevents a panic in pmap_pinit_pd_pae() when applying a lot of memory
pressure and the kernel needs time to recover while swapping.

Reported and fix tested by mvs@, also tested by sthen@

ok mlarkin@, mvs@, kettenis@
---
 sys/arch/i386/i386/pmapae.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sys/arch/i386/i386/pmapae.c b/sys/arch/i386/i386/pmapae.c
index 37e77ecbc3b..c88ec8ffebb 100644
--- a/sys/arch/i386/i386/pmapae.c
+++ b/sys/arch/i386/i386/pmapae.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pmapae.c,v 1.71 2023/05/30 08:30:01 jsg Exp $	*/
+/*	$OpenBSD: pmapae.c,v 1.72 2024/05/30 10:56:24 mpi Exp $	*/
 
 /*
  * Copyright (c) 2006-2008 Michael Shalayeff
@@ -990,7 +990,7 @@ pmap_pinit_pd_pae(struct pmap *pmap)
 	if (cpu_meltdown) {
 		int i;
 
-		va = (vaddr_t)km_alloc(4 * NBPG, &kv_any, &kp_zero, &kd_nowait);
+		va = (vaddr_t)km_alloc(4 * NBPG, &kv_any, &kp_zero, &kd_waitok);
 		if (va == 0)
 			panic("%s: kernel_map out of virtual space!", __func__);
 		if (!pmap_extract(pmap_kernel(),
-- 
2.20.1