From: Maor Gottlieb <maorg@xxxxxxxxxxxx> [ Upstream commit c3d6057e07a5d15be7c69ea545b3f91877808c96 ] SRQ table is accessed both from interrupt and process context, therefore we must use xa_lock_irq. inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. kworker/u17:9/8573 takes: ffff8883e3503d30 (&xa->xa_lock#13){?...}-{2:2}, at: mlx5_cmd_get_srq+0x18/0x70 [mlx5_ib] {IN-HARDIRQ-W} state was registered at: lock_acquire+0xb9/0x3a0 _raw_spin_lock+0x25/0x30 srq_event_notifier+0x2b/0xc0 [mlx5_ib] notifier_call_chain+0x45/0x70 __atomic_notifier_call_chain+0x69/0x100 forward_event+0x36/0xc0 [mlx5_core] notifier_call_chain+0x45/0x70 __atomic_notifier_call_chain+0x69/0x100 mlx5_eq_async_int+0xc5/0x160 [mlx5_core] notifier_call_chain+0x45/0x70 __atomic_notifier_call_chain+0x69/0x100 mlx5_irq_int_handler+0x19/0x30 [mlx5_core] __handle_irq_event_percpu+0x43/0x2a0 handle_irq_event_percpu+0x30/0x70 handle_irq_event+0x34/0x60 handle_edge_irq+0x7c/0x1b0 do_IRQ+0x60/0x110 ret_from_intr+0x0/0x2a default_idle+0x34/0x160 do_idle+0x1ec/0x220 cpu_startup_entry+0x19/0x20 start_secondary+0x153/0x1a0 secondary_startup_64+0xa4/0xb0 irq event stamp: 20907 hardirqs last enabled at (20907): _raw_spin_unlock_irq+0x24/0x30 hardirqs last disabled at (20906): _raw_spin_lock_irq+0xf/0x40 softirqs last enabled at (20746): __do_softirq+0x2c9/0x436 softirqs last disabled at (20681): irq_exit+0xb3/0xc0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&xa->xa_lock#13); <Interrupt> lock(&xa->xa_lock#13); *** DEADLOCK *** 2 locks held by kworker/u17:9/8573: #0: ffff888295218d38 ((wq_completion)mlx5_ib_page_fault){+.+.}-{0:0}, at: process_one_work+0x1f1/0x5f0 #1: ffff888401647e78 ((work_completion)(&pfault->work)){+.+.}-{0:0}, at: process_one_work+0x1f1/0x5f0 stack backtrace: CPU: 0 PID: 8573 Comm: kworker/u17:9 Tainted: GO 5.7.0_for_upstream_min_debug_2020_06_14_11_31_46_41 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 Workqueue: mlx5_ib_page_fault mlx5_ib_eqe_pf_action [mlx5_ib] Call Trace: dump_stack+0x71/0x9b mark_lock+0x4f2/0x590 ? print_shortest_lock_dependencies+0x200/0x200 __lock_acquire+0xa00/0x1eb0 lock_acquire+0xb9/0x3a0 ? mlx5_cmd_get_srq+0x18/0x70 [mlx5_ib] _raw_spin_lock+0x25/0x30 ? mlx5_cmd_get_srq+0x18/0x70 [mlx5_ib] mlx5_cmd_get_srq+0x18/0x70 [mlx5_ib] mlx5_ib_eqe_pf_action+0x257/0xa30 [mlx5_ib] ? process_one_work+0x209/0x5f0 process_one_work+0x27b/0x5f0 ? __schedule+0x280/0x7e0 worker_thread+0x2d/0x3c0 ? process_one_work+0x5f0/0x5f0 kthread+0x111/0x130 ? kthread_park+0x90/0x90 ret_from_fork+0x24/0x30 Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters") Link: https://lore.kernel.org/r/20200712102641.15210-1-leon@xxxxxxxxxx Signed-off-by: Maor Gottlieb <maorg@xxxxxxxxxxxx> Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/infiniband/hw/mlx5/srq_cmd.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/hw/mlx5/srq_cmd.c b/drivers/infiniband/hw/mlx5/srq_cmd.c index 8fc3630a9d4c3..0224231a2e6f8 100644 --- a/drivers/infiniband/hw/mlx5/srq_cmd.c +++ b/drivers/infiniband/hw/mlx5/srq_cmd.c @@ -83,11 +83,11 @@ struct mlx5_core_srq *mlx5_cmd_get_srq(struct mlx5_ib_dev *dev, u32 srqn) struct mlx5_srq_table *table = &dev->srq_table; struct mlx5_core_srq *srq; - xa_lock(&table->array); + xa_lock_irq(&table->array); srq = xa_load(&table->array, srqn); if (srq) refcount_inc(&srq->common.refcount); - xa_unlock(&table->array); + xa_unlock_irq(&table->array); return srq; } -- 2.25.1