[PATCH] RDMA/irdma: Avoid free the non-cqp_request scratch

[Shifeng Li]

When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a
cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when removing
the irdma driver or unplugging its aux device, cqp.sc_cqp will be dereferenced 
as wrong struct in irdma_free_pending_cqp_request().

crash> bt 3669
PID: 3669   TASK: ffff88aef892c000  CPU: 28  COMMAND: "kworker/28:0"
 #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34
 #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2
 #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f
 #3 [fffffe0000549eb8] do_nmi at ffffffff81079582
 #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4
    [exception RIP: native_queued_spin_lock_slowpath+1291]
    RIP: ffffffff8127e72b  RSP: ffff88aa841ef778  RFLAGS: 00000046
    RAX: 0000000000000000  RBX: ffff88b01f849700  RCX: ffffffff8127e47e
    RDX: 0000000000000000  RSI: 0000000000000004  RDI: ffffffff83857ec0
    RBP: ffff88afe3e4efc8   R8: ffffed15fc7c9dfa   R9: ffffed15fc7c9dfa
    R10: 0000000000000001  R11: ffffed15fc7c9df9  R12: 0000000000740000
    R13: ffff88b01f849708  R14: 0000000000000003  R15: ffffed1603f092e1
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
--- <NMI exception stack> ---
 #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b
 #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4
 #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363
 #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma]
 #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma]
 #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma]
 #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma]
 #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb
 #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6
 #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278
 #15 [ffff88aa841efb88] device_del at ffffffff82179d23
 #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice]
 #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice]
 #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a
 #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff
 #20 [ffff88aa841eff10] kthread at ffffffff811d87a0
 #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f

Fixes: 44d9e52977a1 ("RDMA/irdma: Implement device initialization definitions")
Signed-off-by: Shifeng Li <lishifeng1992@xxxxxxx>
---
 drivers/infiniband/hw/irdma/utils.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/hw/irdma/utils.c b/drivers/infiniband/hw/irdma/utils.c
index 445e69e86409..222ec1f761a1 100644
--- a/drivers/infiniband/hw/irdma/utils.c
+++ b/drivers/infiniband/hw/irdma/utils.c
@@ -541,7 +541,7 @@ void irdma_cleanup_pending_cqp_op(struct irdma_pci_f *rf)
 	for (i = 0; i < pending_work; i++) {
 		cqp_request = (struct irdma_cqp_request *)(unsigned long)
 				      cqp->scratch_array[wqe_idx];
-		if (cqp_request)
+		if (cqp_request && cqp_request != (struct irdma_cqp_request *)&cqp->sc_cqp)
 			irdma_free_pending_cqp_request(cqp, cqp_request);
 		wqe_idx = (wqe_idx + 1) % IRDMA_RING_SIZE(cqp->sc_cqp.sq_ring);
 	}
-- 
2.25.1