From 90e88dbae3bf93415fc40654c8ca213523ea556f Mon Sep 17 00:00:00 2001 From: Tim Deegan Date: Thu, 15 Mar 2012 11:12:44 +0000 Subject: [PATCH] x86/mm/paging: Prevent the guest from faulting on the same gfn when dying A crashing guest due to paging may hit an "endless" loop faulting repeatedly on the current paged-out gfn, until the toolstack comes around to killing the domain. Unfortunately domain_crash at this point may not pause the vcpu due to the shutting_down flag, so we pause it explicitly when detecting the condition. Signed-off-by: Andres Lagar-Cavilla Acked-by: Tim Deegan Committed-by: Tim Deegan --- xen/arch/x86/mm/p2m.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c index ba47c99445..cf97617eaf 100644 --- a/xen/arch/x86/mm/p2m.c +++ b/xen/arch/x86/mm/p2m.c @@ -988,6 +988,9 @@ void p2m_mem_paging_populate(struct domain *d, unsigned long gfn) { gdprintk(XENLOG_ERR, "Domain %hu paging gfn %lx yet no ring " "in place\n", d->domain_id, gfn); + /* Prevent the vcpu from faulting repeatedly on the same gfn */ + if ( v->domain == d ) + vcpu_pause_nosync(v); domain_crash(d); return; } -- 2.30.2