This is a note to let you know that I've just added the patch titled
RDMA/mlx5: Use xa_lock_irq when access to SRQ table
to the 5.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
rdma-mlx5-use-xa_lock_irq-when-access-to-srq-table.patch
and it can be found in the queue-5.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit c2330696ae4be966ae060cbdfe6ee6cea0db8b6d
Author: Maor Gottlieb <maorg@xxxxxxxxxxxx>
Date: Sun Jul 12 13:26:41 2020 +0300
RDMA/mlx5: Use xa_lock_irq when access to SRQ table
[ 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>
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;
}
