On 2020-05-21 19:39, Ming Lei wrote: > You may argue that two hw queue may share single managed interrupt, that > is possible if driver plays the trick. But if driver plays the trick in > this way, it is driver's responsibility to guarantee that the managed > irq won't be shutdown if either of the two hctxs are active, such as, > making sure that hctx->cpumask + hctx->cpumask <= this managed interrupt's affinity. > It is definitely one strange enough case, and this patch doesn't > suppose to cover this strange case. But, this patch won't break this > case. Also just be curious, do you have such in-tree case? and are you > sure the driver uses managed interrupt? I'm concerned about the block drivers that use RDMA (NVMeOF, SRP, iSER, ...). The functions that accept an interrupt vector argument (comp_vector), namely ib_alloc_cq() and ib_create_cq(), can be used in such a way that completion interrupts are handled on another CPU than those in hctx->cpumask. Bart.