On Wed, 30 Aug 2023 11:04:00 +0000 "Joel Fernandes (Google)" <joel@xxxxxxxxxxxxxxxxx> wrote: > Currently, for double invoke call_rcu(), will dump rcu_head objects > memory info, if the objects is not allocated from the slab allocator, > the vmalloc_dump_obj() will be invoke and the vmap_area_lock spinlock > need to be held, since the call_rcu() can be invoked in interrupt context, > therefore, there is a possibility of spinlock deadlock scenarios. > > And in Preempt-RT kernel, the rcutorture test also trigger the following > lockdep warning: "possibility of deadlock" sounds like something -stable kernels would like to have fixed. Did you consider the desirability of a -stable backport? If so, are we able to identify a suitable Fixes: target?