From: Mike Marciniszyn mike.marciniszyn@intel.com
[ Upstream commit 4c4b1996b5db688e2dcb8242b0a3bf7b1e845e42 ]
The work_item cancels that occur when a QP is destroyed can elicit the following trace:
workqueue: WQ_MEM_RECLAIM ipoib_wq:ipoib_cm_tx_reap [ib_ipoib] is flushing !WQ_MEM_RECLAIM hfi0_0:_hfi1_do_send [hfi1] WARNING: CPU: 7 PID: 1403 at kernel/workqueue.c:2486 check_flush_dependency+0xb1/0x100 Call Trace: __flush_work.isra.29+0x8c/0x1a0 ? __switch_to_asm+0x40/0x70 __cancel_work_timer+0x103/0x190 ? schedule+0x32/0x80 iowait_cancel_work+0x15/0x30 [hfi1] rvt_reset_qp+0x1f8/0x3e0 [rdmavt] rvt_destroy_qp+0x65/0x1f0 [rdmavt] ? _cond_resched+0x15/0x30 ib_destroy_qp+0xe9/0x230 [ib_core] ipoib_cm_tx_reap+0x21c/0x560 [ib_ipoib] process_one_work+0x171/0x370 worker_thread+0x49/0x3f0 kthread+0xf8/0x130 ? max_active_store+0x80/0x80 ? kthread_bind+0x10/0x10 ret_from_fork+0x35/0x40
Since QP destruction frees memory, hfi1_wq should have the WQ_MEM_RECLAIM.
The hfi1_wq does not allocate memory with GFP_KERNEL or otherwise become entangled with memory reclaim, so this flag is appropriate.
Fixes: 0a226edd203f ("staging/rdma/hfi1: Use parallel workqueue for SDMA engines") Reviewed-by: Michael J. Ruhl michael.j.ruhl@intel.com Signed-off-by: Mike Marciniszyn mike.marciniszyn@intel.com Signed-off-by: Dennis Dalessandro dennis.dalessandro@intel.com Signed-off-by: Jason Gunthorpe jgg@mellanox.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/infiniband/hw/hfi1/init.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/infiniband/hw/hfi1/init.c b/drivers/infiniband/hw/hfi1/init.c index c532ceb0bb9af..b66c4fe8151a1 100644 --- a/drivers/infiniband/hw/hfi1/init.c +++ b/drivers/infiniband/hw/hfi1/init.c @@ -797,7 +797,8 @@ static int create_workqueues(struct hfi1_devdata *dd) ppd->hfi1_wq = alloc_workqueue( "hfi%d_%d", - WQ_SYSFS | WQ_HIGHPRI | WQ_CPU_INTENSIVE, + WQ_SYSFS | WQ_HIGHPRI | WQ_CPU_INTENSIVE | + WQ_MEM_RECLAIM, HFI1_MAX_ACTIVE_WORKQUEUE_ENTRIES, dd->unit, pidx); if (!ppd->hfi1_wq)