On Tuesday, September 09/17/19, 2019 at 14:34:24 +0530, Bernard Metzler wrote: > -----"Jason Gunthorpe" <jgg@xxxxxxxx> wrote: ----- > > >To: "Krishnamraju Eraparaju" <krishna2@xxxxxxxxxxx> > >From: "Jason Gunthorpe" <jgg@xxxxxxxx> > >Date: 09/16/2019 06:28PM > >Cc: "Steve Wise" <larrystevenwise@xxxxxxxxx>, "Bernard Metzler" > ><BMT@xxxxxxxxxxxxxx>, "Sagi Grimberg" <sagi@xxxxxxxxxxx>, > >"linux-rdma@xxxxxxxxxxxxxxx" <linux-rdma@xxxxxxxxxxxxxxx> > >Subject: [EXTERNAL] Re: Re: [PATCH v3] iwcm: don't hold the irq > >disabled lock on iw_rem_ref > > > >On Wed, Sep 11, 2019 at 09:28:16PM +0530, Krishnamraju Eraparaju > >wrote: > >> Hi Steve & Bernard, > >> > >> Thanks for the review comments. > >> I will do those formating changes. > > > >I don't see anything in patchworks, but the consensus is to drop > >Sagi's patch pending this future patch? > > > >Jason > > > This is my impression as well. But consensus should be > explicit...Sagi, what do you think? > > Best regards, > Bernard. > While testing iSER(with my proposed patch applied) I see Chelsio iwarp driver is hitting the below deadlock issue. This is due to iw_rem_ref reordering changes in IWCM. Bernard, how about replacing vmalloc/vfree with kmalloc/kfree, such that freeing of SIW qp resources can be done with spinlocks held? to fix the orginal vfree issue less invasively.. Steve, any suggestions? [ 1230.161871] INFO: task kworker/u12:0:11291 blocked for more than 122 seconds. [ 1230.162147] Not tainted 5.3.0-rc5+ #19 [ 1230.162417] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1230.162911] kworker/u12:0 D13000 11291 2 0x80004080 [ 1230.163186] Workqueue: iw_cm_wq cm_work_handler [ 1230.163456] Call Trace: [ 1230.163718] ? __schedule+0x297/0x510 [ 1230.163986] schedule+0x2e/0x90 [ 1230.164253] schedule_timeout+0x1c0/0x280 [ 1230.164520] ? xas_store+0x23e/0x500 [ 1230.164789] wait_for_completion+0xa2/0x110 [ 1230.165067] ? wake_up_q+0x70/0x70 [ 1230.165336] c4iw_destroy_qp+0x141/0x260 [iw_cxgb4] [ 1230.165611] ? xas_store+0x23e/0x500 [ 1230.165893] ? _cond_resched+0x10/0x20 [ 1230.166160] ? wait_for_completion+0x2e/0x110 [ 1230.166432] ib_destroy_qp_user+0x142/0x230 [ 1230.166699] rdma_destroy_qp+0x1f/0x40 [ 1230.166966] iser_free_ib_conn_res+0x52/0x190 [ib_iser] [ 1230.167241] iser_cleanup_handler.isra.15+0x32/0x60 [ib_iser] [ 1230.167510] iser_cma_handler+0x23b/0x730 [ib_iser] [ 1230.167776] cma_iw_handler+0x154/0x1e0 [ 1230.168037] cm_work_handler+0xb4c/0xd60 [ 1230.168302] process_one_work+0x155/0x380 [ 1230.168564] worker_thread+0x41/0x3b0 [ 1230.168827] kthread+0xf3/0x130 [ 1230.169086] ? process_one_work+0x380/0x380 [ 1230.169350] ? kthread_bind+0x10/0x10 [ 1230.169615] ret_from_fork+0x35/0x40 [ 1230.169885] NMI backtrace for cpu 3
