Re: [PATCH 1/1] iommu/vt-d: Fix possible recursive locking in intel_iommu_init()

[Baolu Lu]

Hi Kevin,

On 2022/7/21 15:39, Tian, Kevin wrote:
> > From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> > Sent: Tuesday, July 19, 2022 7:53 AM
> >
> > @@ -88,7 +89,8 @@ extern struct list_head dmar_drhd_units;
> >   static inline bool dmar_rcu_check(void)
> >   {
> >   	return rwsem_is_locked(&dmar_global_lock) ||
> > -	       system_state == SYSTEM_BOOTING;
> > +	       system_state == SYSTEM_BOOTING ||
> > +	       (IS_ENABLED(CONFIG_INTEL_IOMMU)
> > && !intel_iommu_enabled);
> >   }
>
> intel_iommu_enabled is 0 if CONFIG_INTEL_IOMMU is not set.
>
> same for other similar checks.

Sorry that I didn't get your point. If CONFIG_INTEL_IOMMU is not set,
IS_ENABLED(CONFIG_INTEL_IOMMU) is 0. The adding check has no effect. Did
I miss anything?

Best regards,
baolu