RDMA/irdma: Fix data race on CQP request done

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: 915cc7ac0f8e ("RDMA/irdma: Add miscellaneous utility definitions")
Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Link: https://lore.kernel.org/r/20230711175253.1289-4-shiraz.saleem@intel.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

diff --git a/drivers/infiniband/hw/irdma/hw.c b/drivers/infiniband/hw/irdma/hw.c
index 795f7fd..1cfc03d 100644 (file)
--- 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 (file)
--- 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 (file)
--- 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 @@ irdma_free_pending_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;