KCSAN detects a data race on cqp_request->request_done memory location which is accessed locklessly in irdma_handle_cqp_op while being updated in irdma_cqp_ce_handler. Annotate lockless intent with READ_ONCE/WRITE_ONCE to avoid any compiler optimizations like load fusing and/or KCSAN warning. [222808.417128] BUG: KCSAN: data-race in irdma_cqp_ce_handler [irdma] / irdma_wait_event [irdma] [222808.417532] write to 0xffff8e44107019dc of 1 bytes by task 29658 on cpu 5: [222808.417610] irdma_cqp_ce_handler+0x21e/0x270 [irdma] [222808.417725] cqp_compl_worker+0x1b/0x20 [irdma] [222808.417827] process_one_work+0x4d1/0xa40 [222808.417835] worker_thread+0x319/0x700 [222808.417842] kthread+0x180/0x1b0 [222808.417852] ret_from_fork+0x22/0x30 [222808.417918] read to 0xffff8e44107019dc of 1 bytes by task 29688 on cpu 1: [222808.417995] irdma_wait_event+0x1e2/0x2c0 [irdma] [222808.418099] irdma_handle_cqp_op+0xae/0x170 [irdma] [222808.418202] irdma_cqp_cq_destroy_cmd+0x70/0x90 [irdma] [222808.418308] irdma_puda_dele_rsrc+0x46d/0x4d0 [irdma] [222808.418411] irdma_rt_deinit_hw+0x179/0x1d0 [irdma] [222808.418514] irdma_ib_dealloc_device+0x11/0x40 [irdma] [222808.418618] ib_dealloc_device+0x2a/0x120 [ib_core] [222808.418823] __ib_unregister_device+0xde/0x100 [ib_core] [222808.418981] ib_unregister_device+0x22/0x40 [ib_core] [222808.419142] irdma_ib_unregister_device+0x70/0x90 [irdma] [222808.419248] i40iw_close+0x6f/0xc0 [irdma] [222808.419352] i40e_client_device_unregister+0x14a/0x180 [i40e] [222808.419450] i40iw_remove+0x21/0x30 [irdma] [222808.419554] auxiliary_bus_remove+0x31/0x50 [222808.419563] device_remove+0x69/0xb0 [222808.419572] device_release_driver_internal+0x293/0x360 [222808.419582] driver_detach+0x7c/0xf0 [222808.419592] bus_remove_driver+0x8c/0x150 [222808.419600] driver_unregister+0x45/0x70 [222808.419610] auxiliary_driver_unregister+0x16/0x30 [222808.419618] irdma_exit_module+0x18/0x1e [irdma] [222808.419733] __do_sys_delete_module.constprop.0+0x1e2/0x310 [222808.419745] __x64_sys_delete_module+0x1b/0x30 [222808.419755] do_syscall_64+0x39/0x90 [222808.419763] entry_SYSCALL_64_after_hwframe+0x63/0xcd [222808.419829] value changed: 0x01 -> 0x03 Fixes: 915cc7ac0f8 ("RDMA/irdma: Add miscellaneous utility definitions") Signed-off-by: Shiraz Saleem <shiraz.saleem@xxxxxxxxx> --- drivers/infiniband/hw/irdma/hw.c | 2 +- drivers/infiniband/hw/irdma/main.h | 2 +- drivers/infiniband/hw/irdma/utils.c | 6 +++--- 3 files changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/infiniband/hw/irdma/hw.c b/drivers/infiniband/hw/irdma/hw.c index 795f7fd..1cfc03d 100644 --- a/drivers/infiniband/hw/irdma/hw.c +++ b/drivers/infiniband/hw/irdma/hw.c @@ -2075,7 +2075,7 @@ void irdma_cqp_ce_handler(struct irdma_pci_f *rf, struct irdma_sc_cq *cq) cqp_request->compl_info.error = info.error; if (cqp_request->waiting) { - cqp_request->request_done = true; + WRITE_ONCE(cqp_request->request_done, true); wake_up(&cqp_request->waitq); irdma_put_cqp_request(&rf->cqp, cqp_request); } else { diff --git a/drivers/infiniband/hw/irdma/main.h b/drivers/infiniband/hw/irdma/main.h index def6dd5..2323962 100644 --- a/drivers/infiniband/hw/irdma/main.h +++ b/drivers/infiniband/hw/irdma/main.h @@ -161,8 +161,8 @@ struct irdma_cqp_request { void (*callback_fcn)(struct irdma_cqp_request *cqp_request); void *param; struct irdma_cqp_compl_info compl_info; + bool request_done; /* READ/WRITE_ONCE macros operate on it */ bool waiting:1; - bool request_done:1; bool dynamic:1; }; diff --git a/drivers/infiniband/hw/irdma/utils.c b/drivers/infiniband/hw/irdma/utils.c index 775a799..eb083f7 100644 --- a/drivers/infiniband/hw/irdma/utils.c +++ b/drivers/infiniband/hw/irdma/utils.c @@ -481,7 +481,7 @@ void irdma_free_cqp_request(struct irdma_cqp *cqp, if (cqp_request->dynamic) { kfree(cqp_request); } else { - cqp_request->request_done = false; + WRITE_ONCE(cqp_request->request_done, false); cqp_request->callback_fcn = NULL; cqp_request->waiting = false; @@ -515,7 +515,7 @@ void irdma_put_cqp_request(struct irdma_cqp *cqp, { if (cqp_request->waiting) { cqp_request->compl_info.error = true; - cqp_request->request_done = true; + WRITE_ONCE(cqp_request->request_done, true); wake_up(&cqp_request->waitq); } wait_event_timeout(cqp->remove_wq, @@ -571,7 +571,7 @@ static int irdma_wait_event(struct irdma_pci_f *rf, do { irdma_cqp_ce_handler(rf, &rf->ccq.sc_cq); if (wait_event_timeout(cqp_request->waitq, - cqp_request->request_done, + READ_ONCE(cqp_request->request_done), msecs_to_jiffies(CQP_COMPL_WAIT_TIME_MS))) break; -- 1.8.3.1