From: Maor Gottlieb <maorg@xxxxxxxxxxxx>
SRQ table is accessed both from interrupt and process context,
therefore we must use xa_lock_irqsave.
[ 9878.321379] --------------------------------
[ 9878.322349] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
[ 9878.323667] kworker/u17:9/8573 [HC0[0]:SC0[0]:HE1:SE1] takes:
[ 9878.324894] ffff8883e3503d30 (&xa->xa_lock#13){?...}-{2:2}, at:
mlx5_cmd_get_srq+0x18/0x70 [mlx5_ib]
[ 9878.326816] {IN-HARDIRQ-W} state was registered at:
[ 9878.327905] lock_acquire+0xb9/0x3a0
[ 9878.328720] _raw_spin_lock+0x25/0x30
[ 9878.329475] srq_event_notifier+0x2b/0xc0 [mlx5_ib]
[ 9878.330433] notifier_call_chain+0x45/0x70
[ 9878.331393] __atomic_notifier_call_chain+0x69/0x100
[ 9878.332530] forward_event+0x36/0xc0 [mlx5_core]
[ 9878.333558] notifier_call_chain+0x45/0x70
[ 9878.334418] __atomic_notifier_call_chain+0x69/0x100
[ 9878.335498] mlx5_eq_async_int+0xc5/0x160 [mlx5_core]
[ 9878.336543] notifier_call_chain+0x45/0x70
[ 9878.337354] __atomic_notifier_call_chain+0x69/0x100
[ 9878.338337] mlx5_irq_int_handler+0x19/0x30 [mlx5_core]
[ 9878.339369] __handle_irq_event_percpu+0x43/0x2a0
[ 9878.340382] handle_irq_event_percpu+0x30/0x70
[ 9878.341252] handle_irq_event+0x34/0x60
[ 9878.342020] handle_edge_irq+0x7c/0x1b0
[ 9878.342788] do_IRQ+0x60/0x110
[ 9878.343482] ret_from_intr+0x0/0x2a
[ 9878.344251] default_idle+0x34/0x160
[ 9878.344996] do_idle+0x1ec/0x220
[ 9878.345682] cpu_startup_entry+0x19/0x20
[ 9878.346511] start_secondary+0x153/0x1a0
[ 9878.347328] secondary_startup_64+0xa4/0xb0
[ 9878.348226] irq event stamp: 20907
[ 9878.348953] hardirqs last enabled at (20907): [<ffffffff819f0eb4>]
_raw_spin_unlock_irq+0x24/0x30
[ 9878.350599] hardirqs last disabled at (20906): [<ffffffff819f0cbf>]
_raw_spin_lock_irq+0xf/0x40
[ 9878.352300] softirqs last enabled at (20746): [<ffffffff81c002c9>]
__do_softirq+0x2c9/0x436
[ 9878.353859] softirqs last disabled at (20681): [<ffffffff81139543>]
irq_exit+0xb3/0xc0
[ 9878.355365]
[ 9878.355365] other info that might help us debug this:
[ 9878.356703] Possible unsafe locking scenario:
[ 9878.356703]
[ 9878.357941] CPU0
[ 9878.358522] ----
[ 9878.359109] lock(&xa->xa_lock#13);
[ 9878.359875] <Interrupt>
[ 9878.360504] lock(&xa->xa_lock#13);
[ 9878.361315]
[ 9878.361315] *** DEADLOCK ***
[ 9878.361315]
[ 9878.362632] 2 locks held by kworker/u17:9/8573:
[ 9878.374883] #0: ffff888295218d38
((wq_completion)mlx5_ib_page_fault){+.+.}-{0:0}, at:
process_one_work+0x1f1/0x5f0
[ 9878.376728] #1: ffff888401647e78
((work_completion)(&pfault->work)){+.+.}-{0:0}, at:
process_one_work+0x1f1/0x5f0
[ 9878.378550]
[ 9878.378550] stack backtrace:
[ 9878.379489] CPU: 0 PID: 8573 Comm: kworker/u17:9 Tainted: G
O 5.7.0_for_upstream_min_debug_2020_06_14_11_31_46_41 #1
[ 9878.381730] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
[ 9878.383940] Workqueue: mlx5_ib_page_fault mlx5_ib_eqe_pf_action
[mlx5_ib]
[ 9878.385239] Call Trace:
[ 9878.385822] dump_stack+0x71/0x9b
[ 9878.386519] mark_lock+0x4f2/0x590
[ 9878.387263] ? print_shortest_lock_dependencies+0x200/0x200
[ 9878.388362] __lock_acquire+0xa00/0x1eb0
[ 9878.389133] lock_acquire+0xb9/0x3a0
[ 9878.389854] ? mlx5_cmd_get_srq+0x18/0x70 [mlx5_ib]
[ 9878.390796] _raw_spin_lock+0x25/0x30
[ 9878.391533] ? mlx5_cmd_get_srq+0x18/0x70 [mlx5_ib]
[ 9878.392455] mlx5_cmd_get_srq+0x18/0x70 [mlx5_ib]
[ 9878.393351] mlx5_ib_eqe_pf_action+0x257/0xa30 [mlx5_ib]
[ 9878.394337] ? process_one_work+0x209/0x5f0
[ 9878.395150] process_one_work+0x27b/0x5f0
[ 9878.395939] ? __schedule+0x280/0x7e0
[ 9878.396683] worker_thread+0x2d/0x3c0
[ 9878.397424] ? process_one_work+0x5f0/0x5f0
[ 9878.398249] kthread+0x111/0x130
[ 9878.398926] ? kthread_park+0x90/0x90
[ 9878.399709] ret_from_fork+0x24/0x30
Fixes: b02a29eb8841 ("mlx5: Convert mlx5_srq_table to XArray")
Signed-off-by: Maor Gottlieb <maorg@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
---
drivers/infiniband/hw/mlx5/srq_cmd.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/infiniband/hw/mlx5/srq_cmd.c b/drivers/infiniband/hw/mlx5/srq_cmd.c
index 6f5eadc4d183..be0e5469dad0 100644
--- a/drivers/infiniband/hw/mlx5/srq_cmd.c
+++ b/drivers/infiniband/hw/mlx5/srq_cmd.c
@@ -82,12 +82,13 @@ 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;
+ unsigned long flags;
- xa_lock(&table->array);
+ xa_lock_irqsave(&table->array, flags);
srq = xa_load(&table->array, srqn);
if (srq)
refcount_inc(&srq->common.refcount);
- xa_unlock(&table->array);
+ xa_unlock_irqrestore(&table->array, flags);
return srq;
}
@@ -644,6 +645,7 @@ static int srq_event_notifier(struct notifier_block *nb,
struct mlx5_srq_table *table;
struct mlx5_core_srq *srq;
struct mlx5_eqe *eqe;
+ unsigned long flags;
u32 srqn;
if (type != MLX5_EVENT_TYPE_SRQ_CATAS_ERROR &&
@@ -655,11 +657,11 @@ static int srq_event_notifier(struct notifier_block *nb,
eqe = data;
srqn = be32_to_cpu(eqe->data.qp_srq.qp_srq_n) & 0xffffff;
- xa_lock(&table->array);
+ xa_lock_irqsave(&table->array, flags);
srq = xa_load(&table->array, srqn);
if (srq)
refcount_inc(&srq->common.refcount);
- xa_unlock(&table->array);
+ xa_unlock_irqrestore(&table->array, flags);
if (!srq)
return NOTIFY_OK;
--
2.26.2
