[v4] target/i386: Misc cleanup on KVM PV defs, outdated comments and error handling

[PATCH v4 8/9] target/i386/kvm: Clean up error handling in kvm_arch_init()

Posted by Zhao Liu 2 months ago

Currently, there're following incorrect error handling cases in
kvm_arch_init():
* Missed to handle failure of kvm_get_supported_feature_msrs().
* Missed to return when KVM_CAP_X86_DISABLE_EXITS enabling fails.
* MSR filter related cases called exit() directly instead of returning
  to kvm_init().

Fix the above cases.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
---
v3: new commit.
---
 target/i386/kvm/kvm.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index f68be68eb411..d47476e96813 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -2682,7 +2682,10 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
         return ret;
     }
 
-    kvm_get_supported_feature_msrs(s);
+    ret = kvm_get_supported_feature_msrs(s);
+    if (ret < 0) {
+        return ret;
+    }
 
     uname(&utsname);
     lm_capable_kernel = strcmp(utsname.machine, "x86_64") == 0;
@@ -2740,6 +2743,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
         if (ret < 0) {
             error_report("kvm: guest stopping CPU not supported: %s",
                          strerror(-ret));
+            return ret;
         }
     }
 
@@ -2785,7 +2789,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
         if (ret) {
             error_report("Could not enable user space MSRs: %s",
                          strerror(-ret));
-            exit(1);
+            return ret;
         }
 
         ret = kvm_filter_msr(s, MSR_CORE_THREAD_COUNT,
@@ -2793,7 +2797,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
         if (ret) {
             error_report("Could not install MSR_CORE_THREAD_COUNT handler: %s",
                          strerror(-ret));
-            exit(1);
+            return ret;
         }
     }
 
-- 
2.34.1

Re: [PATCH v4 8/9] target/i386/kvm: Clean up error handling in kvm_arch_init()

Posted by Chen, Zide 1 month, 4 weeks ago


On 7/16/2024 9:10 AM, Zhao Liu wrote:
> Currently, there're following incorrect error handling cases in
> kvm_arch_init():
> * Missed to handle failure of kvm_get_supported_feature_msrs().
> * Missed to return when KVM_CAP_X86_DISABLE_EXITS enabling fails.
> * MSR filter related cases called exit() directly instead of returning
>   to kvm_init().
> 
> Fix the above cases.
> 
> Signed-off-by: Zhao Liu <zhao1.liu@intel.com>

Reviewed-by: Zide Chen <zide.chen@intel.com>


> ---
> v3: new commit.
> ---
>  target/i386/kvm/kvm.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
> index f68be68eb411..d47476e96813 100644
> --- a/target/i386/kvm/kvm.c
> +++ b/target/i386/kvm/kvm.c
> @@ -2682,7 +2682,10 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
>          return ret;
>      }
>  
> -    kvm_get_supported_feature_msrs(s);
> +    ret = kvm_get_supported_feature_msrs(s);
> +    if (ret < 0) {
> +        return ret;
> +    }
>  
>      uname(&utsname);
>      lm_capable_kernel = strcmp(utsname.machine, "x86_64") == 0;
> @@ -2740,6 +2743,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
>          if (ret < 0) {
>              error_report("kvm: guest stopping CPU not supported: %s",
>                           strerror(-ret));
> +            return ret;
>          }
>      }
>  
> @@ -2785,7 +2789,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
>          if (ret) {
>              error_report("Could not enable user space MSRs: %s",
>                           strerror(-ret));
> -            exit(1);
> +            return ret;
>          }
>  
>          ret = kvm_filter_msr(s, MSR_CORE_THREAD_COUNT,
> @@ -2793,7 +2797,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
>          if (ret) {
>              error_report("Could not install MSR_CORE_THREAD_COUNT handler: %s",
>                           strerror(-ret));
> -            exit(1);
> +            return ret;
>          }
>      }
>