Re: [Qemu-devel] [PATCH for-2.9] numa: make -numa parser dynamically allocate CPUs masks

[Igor Mammedov]

On Wed, 28 Dec 2016 15:08:42 -0200
Eduardo Habkost <address@hidden> wrote:

> On Fri, Nov 18, 2016 at 12:02:54PM +0100, Igor Mammedov wrote:
> > so it won't impose an additional limits on max_cpus limits
> > supported by different targets.
> > 
> > It removes global MAX_CPUMASK_BITS constant and need to
> > bump it up whenever max_cpus is being increased for
> > a target above MAX_CPUMASK_BITS value.
> > 
> > Use runtime max_cpus value instead to allocate sufficiently
> > sized node_cpu bitmasks in numa parser.
> > 
> > Signed-off-by: Igor Mammedov <address@hidden>  
> 
> Reviewed-by: Eduardo Habkost <address@hidden>
> 
> As the cpu_index assignment code isn't obviously safe against
> setting cpu_index > max_cpus, I would like to squash this into
> the patch. Is that OK for you?
Go ahead, change looks good to me.

> 
> diff --git a/numa.c b/numa.c
> index 1b6fa78..33f2fd4 100644
> --- a/numa.c
> +++ b/numa.c
> @@ -401,6 +401,7 @@ void numa_post_machine_init(void)
>  
>      CPU_FOREACH(cpu) {
>          for (i = 0; i < nb_numa_nodes; i++) {
> +            assert(cpu->cpu_index < max_cpus);
>              if (test_bit(cpu->cpu_index, numa_info[i].node_cpu)) {
>                  cpu->numa_node = i;
>              }
> @@ -559,6 +560,8 @@ int numa_get_node_for_cpu(int idx)
>  {
>      int i;
>  
> +    assert(idx < max_cpus);
> +
>      for (i = 0; i < nb_numa_nodes; i++) {
>          if (test_bit(idx, numa_info[i].node_cpu)) {
>              break;
>