Re: [PATCH v4 05/11] iommu/sva: Assign a PASID to mm on PASID allocation and free it on mm exit

[zhangfei.gao@xxxxxxxxxxx]

On 2022/4/11 下午10:52, Dave Hansen wrote:
> On 4/11/22 07:44, zhangfei.gao@xxxxxxxxxxx wrote:
> > On 2022/4/11 下午10:36, Dave Hansen wrote:
> > > On 4/11/22 07:20, zhangfei.gao@xxxxxxxxxxx wrote:
> > > > > Is there nothing before this call trace?  Usually there will be at least
> > > > > some warning text.
> > > > I added dump_stack() in ioasid_free.
> > > Hold on a sec, though...
> > >
> > > What's the *problem* here?  Did something break or are you just saying
> > > that something looks weird to _you_?
> > After this, nginx is not working at all, and hardware reports error.
> > Suppose the the master use the ioasid for init, but got freed.
> >
> > hardware reports:
> > [  152.731869] hisi_sec2 0000:76:00.0: qm_acc_do_task_timeout [error status=0x20] found
> > [  152.739657] hisi_sec2 0000:76:00.0: qm_acc_wb_not_ready_timeout [error status=0x40] found
> > [  152.747877] hisi_sec2 0000:76:00.0: sec_fsm_hbeat_rint [error status=0x20] found
> > [  152.755340] hisi_sec2 0000:76:00.0: Controller resetting...
> > [  152.762044] hisi_sec2 0000:76:00.0: QM mailbox operation timeout!
> > [  152.768198] hisi_sec2 0000:76:00.0: Failed to dump sqc!
> > [  152.773490] hisi_sec2 0000:76:00.0: Failed to drain out data for stopping!
> > [  152.781426] hisi_sec2 0000:76:00.0: QM mailbox is busy to start!
> > [  152.787468] hisi_sec2 0000:76:00.0: Failed to dump sqc!
> > [  152.792753] hisi_sec2 0000:76:00.0: Failed to drain out data for stopping!
> > [  152.800685] hisi_sec2 0000:76:00.0: QM mailbox is busy to start!
> > [  152.806730] hisi_sec2 0000:76:00.0: Failed to dump sqc!
> > [  152.812017] hisi_sec2 0000:76:00.0: Failed to drain out data for stopping!
> > [  152.819946] hisi_sec2 0000:76:00.0: QM mailbox is busy to start!
> > [  152.825992] hisi_sec2 0000:76:00.0: Failed to dump sqc!
> That would have been awfully handy information to have in an initial bug report. :)
> Is there a chance you could dump out that ioasid alloc *and* free information in ioasid_alloc/free()?  This could be some kind of problem with the allocator, or with copying the ioasid at fork.
Sure, will add some trace tomorrow.

Thanks Dave