Re: [PATCH] Only call EvtchnFlush on valid Cpus

[Paul Durrant <xadimgnik@xxxxxxxxx>]

On 20/06/2023 15:33, Owen Smith wrote:
> The Evtchn processor array is created using KeQueryMaximumProcessorCountEx, 
> which
> can include processors that do not get initialized.
> Skip cleanup and flushing uninitialized event channels
>
> Signed-off-by: Owen Smith <owen.smith@xxxxxxxxx>
Acked-by: Paul Durrant <paul@xxxxxxx>

> ---
>   src/xenbus/evtchn.c | 6 ++++++
>   1 file changed, 6 insertions(+)
>
> diff --git a/src/xenbus/evtchn.c b/src/xenbus/evtchn.c
> index 2e63edb..ec4ac28 100644
> --- a/src/xenbus/evtchn.c
> +++ b/src/xenbus/evtchn.c
> @@ -1752,10 +1752,16 @@ EvtchnRelease(
>   
>       for (Cpu = 0; Cpu < Context->ProcessorCount; Cpu++) {
>           PXENBUS_EVTCHN_PROCESSOR Processor;
> +        unsigned int             vcpu_id;
> +        NTSTATUS                 status;
>   
>           ASSERT(Context->Processor != NULL);
>           Processor = &Context->Processor[Cpu];
>   
> +        status = SystemProcessorVcpuId(Cpu, &vcpu_id);
> +        if (!NT_SUCCESS(status))
> +            continue;
> +
>           EvtchnFlush(Context, Cpu);
>   
>           (VOID) KeRemoveQueueDpc(&Processor->Dpc);