Commit a5219281 authored by Krzysztof Czurylo's avatar Krzysztof Czurylo Committed by Leon Romanovsky
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RDMA/irdma: Fix data race in irdma_sc_ccq_arm 



Adds a lock around irdma_sc_ccq_arm body to prevent inter-thread data race.
Fixes data race in irdma_sc_ccq_arm() reported by KCSAN:

BUG: KCSAN: data-race in irdma_sc_ccq_arm [irdma] / irdma_sc_ccq_arm [irdma]

read to 0xffff9d51b4034220 of 8 bytes by task 255 on cpu 11:
 irdma_sc_ccq_arm+0x36/0xd0 [irdma]
 irdma_cqp_ce_handler+0x300/0x310 [irdma]
 cqp_compl_worker+0x2a/0x40 [irdma]
 process_one_work+0x402/0x7e0
 worker_thread+0xb3/0x6d0
 kthread+0x178/0x1a0
 ret_from_fork+0x2c/0x50

write to 0xffff9d51b4034220 of 8 bytes by task 89 on cpu 3:
 irdma_sc_ccq_arm+0x7e/0xd0 [irdma]
 irdma_cqp_ce_handler+0x300/0x310 [irdma]
 irdma_wait_event+0xd4/0x3e0 [irdma]
 irdma_handle_cqp_op+0xa5/0x220 [irdma]
 irdma_hw_flush_wqes+0xb1/0x300 [irdma]
 irdma_flush_wqes+0x22e/0x3a0 [irdma]
 irdma_cm_disconn_true+0x4c7/0x5d0 [irdma]
 irdma_disconnect_worker+0x35/0x50 [irdma]
 process_one_work+0x402/0x7e0
 worker_thread+0xb3/0x6d0
 kthread+0x178/0x1a0
 ret_from_fork+0x2c/0x50

value changed: 0x0000000000024000 -> 0x0000000000034000

Fixes: 3f49d684 ("RDMA/irdma: Implement HW Admin Queue OPs")
Signed-off-by: default avatarKrzysztof Czurylo <krzysztof.czurylo@intel.com>
Signed-off-by: default avatarTatyana Nikolova <tatyana.e.nikolova@intel.com>
Link: https://patch.msgid.link/20251125025350.180-2-tatyana.e.nikolova@intel.com


Signed-off-by: default avatarLeon Romanovsky <leon@kernel.org>
parent 4022c7b6

drivers/infiniband/hw/irdma/ctrl.c

+3 −0
Original line number Diff line number Diff line
@@ -3868,11 +3868,13 @@ int irdma_sc_cqp_destroy(struct irdma_sc_cqp *cqp) 
 */

void irdma_sc_ccq_arm(struct irdma_sc_cq *ccq)

{

	unsigned long flags;

	u64 temp_val;

	u16 sw_cq_sel;

	u8 arm_next_se;

	u8 arm_seq_num;



	spin_lock_irqsave(&ccq->dev->cqp_lock, flags);

	get_64bit_val(ccq->cq_uk.shadow_area, 32, &temp_val);

	sw_cq_sel = (u16)FIELD_GET(IRDMA_CQ_DBSA_SW_CQ_SELECT, temp_val);

	arm_next_se = (u8)FIELD_GET(IRDMA_CQ_DBSA_ARM_NEXT_SE, temp_val);
@@ -3883,6 +3885,7 @@ void irdma_sc_ccq_arm(struct irdma_sc_cq *ccq) 
		   FIELD_PREP(IRDMA_CQ_DBSA_ARM_NEXT_SE, arm_next_se) |

		   FIELD_PREP(IRDMA_CQ_DBSA_ARM_NEXT, 1);

	set_64bit_val(ccq->cq_uk.shadow_area, 32, temp_val);

	spin_unlock_irqrestore(&ccq->dev->cqp_lock, flags);



	dma_wmb(); /* make sure shadow area is updated before arming */