> On 8 Sep 2021, at 14:04, Juergen Gross <[email protected]> wrote:
>
> In case a domain is created with a cpupool other than Pool-0 specified
> it will be moved to that cpupool before any vcpus are allocated.
>
> This will lead to a NULL pointer dereference in sched_move_domain().
>
> Fix that by tolerating vcpus not being allocated yet.
>
> Fixes: 70fadc41635b9b6 ("xen/cpupool: support moving domain between cpupools
> with different granularity")
> Reported-by: Bertrand Marquis <[email protected]>
> Signed-off-by: Juergen Gross <[email protected]>
Reviewed-by: Luca Fancellu <[email protected]>
> ---
> V2:
> - Only test for vcpu[0] not being present (Jan Beulich)
> ---
> xen/common/sched/core.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/xen/common/sched/core.c b/xen/common/sched/core.c
> index 8d178baf3d..8f4b1ca10d 100644
> --- a/xen/common/sched/core.c
> +++ b/xen/common/sched/core.c
> @@ -651,7 +651,7 @@ int sched_move_domain(struct domain *d, struct cpupool *c)
> struct scheduler *old_ops = dom_scheduler(d);
> void *old_domdata;
> unsigned int gran = cpupool_get_granularity(c);
> - unsigned int n_units = DIV_ROUND_UP(d->max_vcpus, gran);
> + unsigned int n_units = d->vcpu[0] ? DIV_ROUND_UP(d->max_vcpus, gran) : 0;
> int ret = 0;
>
> for_each_vcpu ( d, v )
> --
> 2.26.2
>
>
