xen/arm: domain_build: Require the property "cpus" when building a domU

The 3rd argument of function dt_property_read_u32() is only valid when
the call succeeded. So we cannot assume the value will not be modifed
in case of failure.

The documentation of Dom0less does not give a default value when the
property "cpus" is not set. So require the property in the configuration.

Coverity-ID: 1476825
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Release-acked-by: Juergen Gross <jgross@suse.com>

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 31af989e639226fd2ffa84f3e2956a4743b081a2..c92f8c6be11e65c95b53499b695803d9e8a90edf 100644 (file)
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -2069,7 +2069,6 @@ void __init create_domUs(void)
             .arch.gic_version = XEN_DOMCTL_CONFIG_GIC_NATIVE,
             .arch.nr_spis = 0,
             .flags = XEN_DOMCTL_CDF_hvm_guest | XEN_DOMCTL_CDF_hap,
-            .max_vcpus = 1,
             .max_evtchn_port = -1,
             .max_grant_frames = 64,
             .max_maptrack_frames = 1024,
@@ -2080,7 +2079,10 @@ void __init create_domUs(void)
 
         if ( dt_property_read_bool(node, "vpl011") )
             d_cfg.arch.nr_spis = GUEST_VPL011_SPI - 32 + 1;
-        dt_property_read_u32(node, "cpus", &d_cfg.max_vcpus);
+
+        if ( !dt_property_read_u32(node, "cpus", &d_cfg.max_vcpus) )
+            panic("Missing property 'cpus' for domain %s\n",
+                  dt_node_name(node));
 
         d = domain_create(++max_init_domid, &d_cfg, false);
         if ( IS_ERR(d) )