From: Andrew Cooper <andrew.cooper3@citrix.com>
Date: Thu, 29 Nov 2018 18:17:01 +0000 (+0000)
Subject: tools/libxc: Fix error handling in get_cpuid_domain_info()
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=82855aba5bf91e50c81526167c11d4aeaf665e66;p=people%2Froyger%2Fxen.git

tools/libxc: Fix error handling in get_cpuid_domain_info()

get_cpuid_domain_info() has two conflicting return styles - either -error for
local failures, or -1/errno for hypercall failures.  Switch to consistently
use -error.

While fixing the xc_get_cpu_featureset(), take the opportunity to remove the
redundancy and move it to be adjacent to the other featureset handling.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
---

diff --git a/tools/libxc/xc_cpuid_x86.c b/tools/libxc/xc_cpuid_x86.c
index 13862b9761..098affe3c6 100644
--- a/tools/libxc/xc_cpuid_x86.c
+++ b/tools/libxc/xc_cpuid_x86.c
@@ -336,13 +336,22 @@ static int get_cpuid_domain_info(xc_interface *xch, uint32_t domid,
             if ( featureset[i] != 0 )
                 return -EOPNOTSUPP;
     }
+    else
+    {
+        rc = xc_get_cpu_featureset(xch, (info->hvm
+                                         ? XEN_SYSCTL_cpu_featureset_hvm
+                                         : XEN_SYSCTL_cpu_featureset_pv),
+                                   &host_nr_features, info->featureset);
+        if ( rc )
+            return -errno;
+    }
 
     /* Get xstate information. */
     domctl.cmd = XEN_DOMCTL_getvcpuextstate;
     domctl.domain = domid;
     rc = do_domctl(xch, &domctl);
     if ( rc )
-        return rc;
+        return -errno;
 
     info->xfeature_mask = domctl.u.vcpuextstate.xfeature_mask;
 
@@ -352,23 +361,15 @@ static int get_cpuid_domain_info(xc_interface *xch, uint32_t domid,
 
         rc = xc_hvm_param_get(xch, domid, HVM_PARAM_PAE_ENABLED, &val);
         if ( rc )
-            return rc;
+            return -errno;
 
         info->pae = !!val;
 
         rc = xc_hvm_param_get(xch, domid, HVM_PARAM_NESTEDHVM, &val);
         if ( rc )
-            return rc;
+            return -errno;
 
         info->nestedhvm = !!val;
-
-        if ( !featureset )
-        {
-            rc = xc_get_cpu_featureset(xch, XEN_SYSCTL_cpu_featureset_hvm,
-                                       &host_nr_features, info->featureset);
-            if ( rc )
-                return rc;
-        }
     }
     else
     {
@@ -376,17 +377,9 @@ static int get_cpuid_domain_info(xc_interface *xch, uint32_t domid,
 
         rc = xc_domain_get_guest_width(xch, domid, &width);
         if ( rc )
-            return rc;
+            return -errno;
 
         info->pv64 = (width == 8);
-
-        if ( !featureset )
-        {
-            rc = xc_get_cpu_featureset(xch, XEN_SYSCTL_cpu_featureset_pv,
-                                       &host_nr_features, info->featureset);
-            if ( rc )
-                return rc;
-        }
     }
 
     return 0;