From: gkoehler <gkoehler@openbsd.org>
Date: Tue, 4 Jun 2024 17:31:59 +0000 (+0000)
Subject: Allow sbld allocation to fail when PMAP_CANFAIL.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=9e6587aee4fdcf19b18481dd57a0bfad1c63c29c;p=openbsd

Allow sbld allocation to fail when PMAP_CANFAIL.

pool_get in powerpc64's pmap might fail when uvm_km_pages.free == 0.
This might cause KASSERT(slbd) to panic 'kernel diagnostic assertion
"sbld" failed'.  Remove this KASSERT and add a check for PMAP_CANFAIL.
pmap_enter calls without PMAP_CANFAIL might still panic.

ok mpi@ jca@
---

diff --git a/sys/arch/powerpc64/powerpc64/pmap.c b/sys/arch/powerpc64/powerpc64/pmap.c
index 53c2badc438..9034952f5c8 100644
--- a/sys/arch/powerpc64/powerpc64/pmap.c
+++ b/sys/arch/powerpc64/powerpc64/pmap.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pmap.c,v 1.61 2024/04/03 19:30:59 gkoehler Exp $ */
+/*	$OpenBSD: pmap.c,v 1.62 2024/06/04 17:31:59 gkoehler Exp $ */
 
 /*
  * Copyright (c) 2015 Martin Pieuchot
@@ -602,7 +602,11 @@ pmap_vp_enter(pmap_t pm, vaddr_t va, struct pte_desc *pted, int flags)
 	slbd = pmap_slbd_lookup(pm, va);
 	if (slbd == NULL) {
 		slbd = pmap_slbd_alloc(pm, va);
-		KASSERT(slbd);
+		if (slbd == NULL) {
+			if ((flags & PMAP_CANFAIL) == 0)
+				panic("%s: unable to allocate slbd", __func__);
+			return ENOMEM;
+		}
 	}
 
 	vp1 = slbd->slbd_vp;