Re: [Xen-devel] [PATCH for 4.6] x86/VPMU: Set VPMU context pointer to NULL when freeing it

[Wei Liu <wei.liu2@xxxxxxxxxx>]

On Tue, Sep 08, 2015 at 10:55:52PM -0400, Boris Ostrovsky wrote:
> Otherwise we may hit assertion in vpmu_initialise() if vcpu is offlined
> and then onlined again.
> 
> For tidyness, set priv_context to NULL as well.
> 
> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>

Release-acked-by: Wei Liu <wei.liu2@xxxxxxxxxx>

> ---
>  xen/arch/x86/cpu/vpmu_amd.c   | 2 ++
>  xen/arch/x86/cpu/vpmu_intel.c | 2 ++
>  2 files changed, 4 insertions(+)
> 
> diff --git a/xen/arch/x86/cpu/vpmu_amd.c b/xen/arch/x86/cpu/vpmu_amd.c
> index 825be72..04da81a 100644
> --- a/xen/arch/x86/cpu/vpmu_amd.c
> +++ b/xen/arch/x86/cpu/vpmu_amd.c
> @@ -438,6 +438,8 @@ static void amd_vpmu_destroy(struct vcpu *v)
>          amd_vpmu_unset_msr_bitmap(v);
>  
>      xfree(vpmu->context);
> +    vpmu->context = NULL;
> +    vpmu->priv_context = NULL;
>  
>      if ( vpmu_is_set(vpmu, VPMU_RUNNING) )
>          release_pmu_ownship(PMU_OWNER_HVM);
> diff --git a/xen/arch/x86/cpu/vpmu_intel.c b/xen/arch/x86/cpu/vpmu_intel.c
> index b3750d7..12f80ae 100644
> --- a/xen/arch/x86/cpu/vpmu_intel.c
> +++ b/xen/arch/x86/cpu/vpmu_intel.c
> @@ -828,7 +828,9 @@ static void core2_vpmu_destroy(struct vcpu *v)
>      struct vpmu_struct *vpmu = vcpu_vpmu(v);
>  
>      xfree(vpmu->context);
> +    vpmu->context = NULL;
>      xfree(vpmu->priv_context);
> +    vpmu->priv_context = NULL;
>      if ( has_hvm_container_vcpu(v) && cpu_has_vmx_msr_bitmap )
>          core2_vpmu_unset_msr_bitmap(v->arch.hvm_vmx.msr_bitmap);
>      release_pmu_ownship(PMU_OWNER_HVM);
> -- 
> 1.8.1.4

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel