[PATCH v2] x86/MCE: bypass uninitialized vcpu in vMCE injection

[PATCH v2] x86/MCE: bypass uninitialized vcpu in vMCE injection

[Kai Huang]

Dom0 may bring up less number of vCPUs than xen hypervisor actually created for
it, and in this case, on Intel platform, vMCE injection to dom0 will fail due to
injecting vMCE to uninitialized vcpu, and cause dom0 crash.

Signed-off-by: Kai Huang <kai.huang@linux.intel.com>
---
 xen/arch/x86/cpu/mcheck/vmce.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/xen/arch/x86/cpu/mcheck/vmce.c b/xen/arch/x86/cpu/mcheck/vmce.c
index c83375e..73733df 100644
--- a/xen/arch/x86/cpu/mcheck/vmce.c
+++ b/xen/arch/x86/cpu/mcheck/vmce.c
@@ -356,6 +356,10 @@ int inject_vmce(struct domain *d, int vcpu)
         if ( vcpu != VMCE_INJECT_BROADCAST && vcpu != v->vcpu_id )
             continue;
 
+        /* Don't inject to uninitialized VCPU. */
+        if ( !v->is_initialised )
+            continue;
+
         if ( (has_hvm_container_domain(d) ||
               guest_has_trap_callback(d, v->vcpu_id, TRAP_machine_check)) &&
              !test_and_set_bool(v->mce_pending) )
-- 
1.9.1

Re: [PATCH v2] x86/MCE: bypass uninitialized vcpu in vMCE injection

[Kai Huang]

Hi Egger, Jan, Jinsong,

Ping. Would you take a look again?

Thanks,
-Kai
On 05/09/2014 10:34 AM, Kai Huang wrote:
> Dom0 may bring up less number of vCPUs than xen hypervisor actually created for
> it, and in this case, on Intel platform, vMCE injection to dom0 will fail due to
> injecting vMCE to uninitialized vcpu, and cause dom0 crash.
>
> Signed-off-by: Kai Huang <kai.huang@linux.intel.com>
> ---
>   xen/arch/x86/cpu/mcheck/vmce.c | 4 ++++
>   1 file changed, 4 insertions(+)
>
> diff --git a/xen/arch/x86/cpu/mcheck/vmce.c b/xen/arch/x86/cpu/mcheck/vmce.c
> index c83375e..73733df 100644
> --- a/xen/arch/x86/cpu/mcheck/vmce.c
> +++ b/xen/arch/x86/cpu/mcheck/vmce.c
> @@ -356,6 +356,10 @@ int inject_vmce(struct domain *d, int vcpu)
>           if ( vcpu != VMCE_INJECT_BROADCAST && vcpu != v->vcpu_id )
>               continue;
>   
> +        /* Don't inject to uninitialized VCPU. */
> +        if ( !v->is_initialised )
> +            continue;
> +
>           if ( (has_hvm_container_domain(d) ||
>                 guest_has_trap_callback(d, v->vcpu_id, TRAP_machine_check)) &&
>                !test_and_set_bool(v->mce_pending) )

Re: [PATCH v2] x86/MCE: bypass uninitialized vcpu in vMCE injection

[Jan Beulich]

>>> On 12.05.14 at 04:01, <kai.huang@linux.intel.com> wrote:
> Hi Egger, Jan, Jinsong,
> 
> Ping. Would you take a look again?

Mind being a little more patient? You sent this on Friday, i.e. taking the
weekend into account, you did give it just about a day before pinging.
If you pinged after a week, that would be acceptable.

Jan

Re: [PATCH v2] x86/MCE: bypass uninitialized vcpu in vMCE injection

[Kai Huang]

On 05/12/2014 05:00 PM, Jan Beulich wrote:
>>>> On 12.05.14 at 04:01, <kai.huang@linux.intel.com> wrote:
>> Hi Egger, Jan, Jinsong,
>>
>> Ping. Would you take a look again?
> Mind being a little more patient? You sent this on Friday, i.e. taking the
> weekend into account, you did give it just about a day before pinging.
> If you pinged after a week, that would be acceptable.
Sorry that not familiar with this. Will follow in the future.

Thanks,
-Kai
>
> Jan
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel

Re: [PATCH v2] x86/MCE: bypass uninitialized vcpu in vMCE injection

[Egger, Christoph]

On 09.05.14 04:34, Kai Huang wrote:
> Dom0 may bring up less number of vCPUs than xen hypervisor actually created for
> it, and in this case, on Intel platform, vMCE injection to dom0 will fail due to
> injecting vMCE to uninitialized vcpu, and cause dom0 crash.
> 
> Signed-off-by: Kai Huang <kai.huang@linux.intel.com>

Acked-by: Christoph Egger <chegger@amazon.de>

> ---
>  xen/arch/x86/cpu/mcheck/vmce.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/xen/arch/x86/cpu/mcheck/vmce.c b/xen/arch/x86/cpu/mcheck/vmce.c
> index c83375e..73733df 100644
> --- a/xen/arch/x86/cpu/mcheck/vmce.c
> +++ b/xen/arch/x86/cpu/mcheck/vmce.c
> @@ -356,6 +356,10 @@ int inject_vmce(struct domain *d, int vcpu)
>          if ( vcpu != VMCE_INJECT_BROADCAST && vcpu != v->vcpu_id )
>              continue;
>  
> +        /* Don't inject to uninitialized VCPU. */
> +        if ( !v->is_initialised )
> +            continue;
> +
>          if ( (has_hvm_container_domain(d) ||
>                guest_has_trap_callback(d, v->vcpu_id, TRAP_machine_check)) &&
>               !test_and_set_bool(v->mce_pending) )
>