From de5c95d0f518537f59ee5aef762abc46f868c377 Mon Sep 17 00:00:00 2001 From: Selvin Xavier Date: Thu, 20 Sep 2018 22:33:00 -0700 Subject: RDMA/bnxt_re: Fix system crash during RDMA resource initialization bnxt_re_ib_reg acquires and releases the rtnl lock whenever it accesses the L2 driver. The following sequence can trigger a crash Acquires the rtnl_lock -> Registers roce driver callback with L2 driver -> release the rtnl lock bnxt_re acquires the rtnl_lock -> Request for MSIx vectors -> release the rtnl_lock Issue happens when bnxt_re proceeds with remaining part of initialization and L2 driver invokes bnxt_ulp_irq_stop as a part of bnxt_open_nic. The crash is in bnxt_qplib_nq_stop_irq as the NQ structures are not initialized yet, [ 3551.726647] BUG: unable to handle kernel NULL pointer dereference at (null) [ 3551.726656] IP: [] bnxt_qplib_nq_stop_irq+0x59/0xb0 [bnxt_re] [ 3551.726674] PGD 0 [ 3551.726679] Oops: 0002 1 SMP ... [ 3551.726822] Hardware name: Dell Inc. PowerEdge R720/08RW36, BIOS 2.4.3 07/09/2014 [ 3551.726826] task: ffff97e30eec5ee0 ti: ffff97e3173bc000 task.ti: ffff97e3173bc000 [ 3551.726829] RIP: 0010:[] [] bnxt_qplib_nq_stop_irq+0x59/0xb0 [bnxt_re] ... [ 3551.726872] Call Trace: [ 3551.726886] [] bnxt_re_stop_irq+0x4e/0x70 [bnxt_re] [ 3551.726899] [] bnxt_ulp_irq_stop+0x43/0x70 [bnxt_en] [ 3551.726908] [] bnxt_reserve_rings+0x174/0x1e0 [bnxt_en] [ 3551.726917] [] __bnxt_open_nic+0x368/0x9a0 [bnxt_en] [ 3551.726925] [] bnxt_open_nic+0x1b/0x50 [bnxt_en] [ 3551.726934] [] bnxt_setup_mq_tc+0x11f/0x260 [bnxt_en] [ 3551.726943] [] bnxt_dcbnl_ieee_setets+0xb8/0x1f0 [bnxt_en] [ 3551.726954] [] dcbnl_ieee_set+0x9a/0x250 [ 3551.726966] [] ? __alloc_skb+0xa1/0x2d0 [ 3551.726972] [] dcb_doit+0x13a/0x210 [ 3551.726981] [] rtnetlink_rcv_msg+0xa7/0x260 [ 3551.726989] [] ? rtnl_unicast+0x20/0x30 [ 3551.726996] [] ? __kmalloc_node_track_caller+0x58/0x290 [ 3551.727002] [] ? dcb_doit+0x166/0x210 [ 3551.727007] [] ? __alloc_skb+0x8d/0x2d0 [ 3551.727012] [] ? rtnl_newlink+0x880/0x880 ... [ 3551.727104] [] system_call_fastpath+0x1c/0x21 ... [ 3551.727164] RIP [] bnxt_qplib_nq_stop_irq+0x59/0xb0 [bnxt_re] [ 3551.727175] RSP [ 3551.727177] CR2: 0000000000000000 Avoid this inconsistent state and system crash by acquiring the rtnl lock for the entire duration of device initialization. Re-factor the code to remove the rtnl lock from the individual function and acquire and release it from the caller. Fixes: 1ac5a4047975 ("RDMA/bnxt_re: Add bnxt_re RoCE driver") Fixes: 6e04b1035689 ("RDMA/bnxt_re: Fix broken RoCE driver due to recent L2 driver changes") Signed-off-by: Selvin Xavier Signed-off-by: Jason Gunthorpe --- drivers/infiniband/hw/bnxt_re/main.c | 93 +++++++++++++++--------------------- 1 file changed, 38 insertions(+), 55 deletions(-) (limited to 'drivers') diff --git a/drivers/infiniband/hw/bnxt_re/main.c b/drivers/infiniband/hw/bnxt_re/main.c index 20b9f31052bf..85cd1a3593d6 100644 --- a/drivers/infiniband/hw/bnxt_re/main.c +++ b/drivers/infiniband/hw/bnxt_re/main.c @@ -78,7 +78,7 @@ static struct list_head bnxt_re_dev_list = LIST_HEAD_INIT(bnxt_re_dev_list); /* Mutex to protect the list of bnxt_re devices added */ static DEFINE_MUTEX(bnxt_re_dev_lock); static struct workqueue_struct *bnxt_re_wq; -static void bnxt_re_ib_unreg(struct bnxt_re_dev *rdev, bool lock_wait); +static void bnxt_re_ib_unreg(struct bnxt_re_dev *rdev); /* SR-IOV helper functions */ @@ -182,7 +182,7 @@ static void bnxt_re_shutdown(void *p) if (!rdev) return; - bnxt_re_ib_unreg(rdev, false); + bnxt_re_ib_unreg(rdev); } static void bnxt_re_stop_irq(void *handle) @@ -251,7 +251,7 @@ static struct bnxt_ulp_ops bnxt_re_ulp_ops = { /* Driver registration routines used to let the networking driver (bnxt_en) * to know that the RoCE driver is now installed */ -static int bnxt_re_unregister_netdev(struct bnxt_re_dev *rdev, bool lock_wait) +static int bnxt_re_unregister_netdev(struct bnxt_re_dev *rdev) { struct bnxt_en_dev *en_dev; int rc; @@ -260,14 +260,9 @@ static int bnxt_re_unregister_netdev(struct bnxt_re_dev *rdev, bool lock_wait) return -EINVAL; en_dev = rdev->en_dev; - /* Acquire rtnl lock if it is not invokded from netdev event */ - if (lock_wait) - rtnl_lock(); rc = en_dev->en_ops->bnxt_unregister_device(rdev->en_dev, BNXT_ROCE_ULP); - if (lock_wait) - rtnl_unlock(); return rc; } @@ -281,14 +276,12 @@ static int bnxt_re_register_netdev(struct bnxt_re_dev *rdev) en_dev = rdev->en_dev; - rtnl_lock(); rc = en_dev->en_ops->bnxt_register_device(en_dev, BNXT_ROCE_ULP, &bnxt_re_ulp_ops, rdev); - rtnl_unlock(); return rc; } -static int bnxt_re_free_msix(struct bnxt_re_dev *rdev, bool lock_wait) +static int bnxt_re_free_msix(struct bnxt_re_dev *rdev) { struct bnxt_en_dev *en_dev; int rc; @@ -298,13 +291,9 @@ static int bnxt_re_free_msix(struct bnxt_re_dev *rdev, bool lock_wait) en_dev = rdev->en_dev; - if (lock_wait) - rtnl_lock(); rc = en_dev->en_ops->bnxt_free_msix(rdev->en_dev, BNXT_ROCE_ULP); - if (lock_wait) - rtnl_unlock(); return rc; } @@ -320,7 +309,6 @@ static int bnxt_re_request_msix(struct bnxt_re_dev *rdev) num_msix_want = min_t(u32, BNXT_RE_MAX_MSIX, num_online_cpus()); - rtnl_lock(); num_msix_got = en_dev->en_ops->bnxt_request_msix(en_dev, BNXT_ROCE_ULP, rdev->msix_entries, num_msix_want); @@ -335,7 +323,6 @@ static int bnxt_re_request_msix(struct bnxt_re_dev *rdev) } rdev->num_msix = num_msix_got; done: - rtnl_unlock(); return rc; } @@ -358,24 +345,18 @@ static void bnxt_re_fill_fw_msg(struct bnxt_fw_msg *fw_msg, void *msg, fw_msg->timeout = timeout; } -static int bnxt_re_net_ring_free(struct bnxt_re_dev *rdev, u16 fw_ring_id, - bool lock_wait) +static int bnxt_re_net_ring_free(struct bnxt_re_dev *rdev, u16 fw_ring_id) { struct bnxt_en_dev *en_dev = rdev->en_dev; struct hwrm_ring_free_input req = {0}; struct hwrm_ring_free_output resp; struct bnxt_fw_msg fw_msg; - bool do_unlock = false; int rc = -EINVAL; if (!en_dev) return rc; memset(&fw_msg, 0, sizeof(fw_msg)); - if (lock_wait) { - rtnl_lock(); - do_unlock = true; - } bnxt_re_init_hwrm_hdr(rdev, (void *)&req, HWRM_RING_FREE, -1, -1); req.ring_type = RING_ALLOC_REQ_RING_TYPE_L2_CMPL; @@ -386,8 +367,6 @@ static int bnxt_re_net_ring_free(struct bnxt_re_dev *rdev, u16 fw_ring_id, if (rc) dev_err(rdev_to_dev(rdev), "Failed to free HW ring:%d :%#x", req.ring_id, rc); - if (do_unlock) - rtnl_unlock(); return rc; } @@ -405,7 +384,6 @@ static int bnxt_re_net_ring_alloc(struct bnxt_re_dev *rdev, dma_addr_t *dma_arr, return rc; memset(&fw_msg, 0, sizeof(fw_msg)); - rtnl_lock(); bnxt_re_init_hwrm_hdr(rdev, (void *)&req, HWRM_RING_ALLOC, -1, -1); req.enables = 0; req.page_tbl_addr = cpu_to_le64(dma_arr[0]); @@ -426,27 +404,21 @@ static int bnxt_re_net_ring_alloc(struct bnxt_re_dev *rdev, dma_addr_t *dma_arr, if (!rc) *fw_ring_id = le16_to_cpu(resp.ring_id); - rtnl_unlock(); return rc; } static int bnxt_re_net_stats_ctx_free(struct bnxt_re_dev *rdev, - u32 fw_stats_ctx_id, bool lock_wait) + u32 fw_stats_ctx_id) { struct bnxt_en_dev *en_dev = rdev->en_dev; struct hwrm_stat_ctx_free_input req = {0}; struct bnxt_fw_msg fw_msg; - bool do_unlock = false; int rc = -EINVAL; if (!en_dev) return rc; memset(&fw_msg, 0, sizeof(fw_msg)); - if (lock_wait) { - rtnl_lock(); - do_unlock = true; - } bnxt_re_init_hwrm_hdr(rdev, (void *)&req, HWRM_STAT_CTX_FREE, -1, -1); req.stat_ctx_id = cpu_to_le32(fw_stats_ctx_id); @@ -457,8 +429,6 @@ static int bnxt_re_net_stats_ctx_free(struct bnxt_re_dev *rdev, dev_err(rdev_to_dev(rdev), "Failed to free HW stats context %#x", rc); - if (do_unlock) - rtnl_unlock(); return rc; } @@ -478,7 +448,6 @@ static int bnxt_re_net_stats_ctx_alloc(struct bnxt_re_dev *rdev, return rc; memset(&fw_msg, 0, sizeof(fw_msg)); - rtnl_lock(); bnxt_re_init_hwrm_hdr(rdev, (void *)&req, HWRM_STAT_CTX_ALLOC, -1, -1); req.update_period_ms = cpu_to_le32(1000); @@ -490,7 +459,6 @@ static int bnxt_re_net_stats_ctx_alloc(struct bnxt_re_dev *rdev, if (!rc) *fw_stats_ctx_id = le32_to_cpu(resp.stat_ctx_id); - rtnl_unlock(); return rc; } @@ -929,19 +897,19 @@ fail: return rc; } -static void bnxt_re_free_nq_res(struct bnxt_re_dev *rdev, bool lock_wait) +static void bnxt_re_free_nq_res(struct bnxt_re_dev *rdev) { int i; for (i = 0; i < rdev->num_msix - 1; i++) { - bnxt_re_net_ring_free(rdev, rdev->nq[i].ring_id, lock_wait); + bnxt_re_net_ring_free(rdev, rdev->nq[i].ring_id); bnxt_qplib_free_nq(&rdev->nq[i]); } } -static void bnxt_re_free_res(struct bnxt_re_dev *rdev, bool lock_wait) +static void bnxt_re_free_res(struct bnxt_re_dev *rdev) { - bnxt_re_free_nq_res(rdev, lock_wait); + bnxt_re_free_nq_res(rdev); if (rdev->qplib_res.dpi_tbl.max) { bnxt_qplib_dealloc_dpi(&rdev->qplib_res, @@ -1219,7 +1187,7 @@ static int bnxt_re_setup_qos(struct bnxt_re_dev *rdev) return 0; } -static void bnxt_re_ib_unreg(struct bnxt_re_dev *rdev, bool lock_wait) +static void bnxt_re_ib_unreg(struct bnxt_re_dev *rdev) { int i, rc; @@ -1234,28 +1202,27 @@ static void bnxt_re_ib_unreg(struct bnxt_re_dev *rdev, bool lock_wait) cancel_delayed_work(&rdev->worker); bnxt_re_cleanup_res(rdev); - bnxt_re_free_res(rdev, lock_wait); + bnxt_re_free_res(rdev); if (test_and_clear_bit(BNXT_RE_FLAG_RCFW_CHANNEL_EN, &rdev->flags)) { rc = bnxt_qplib_deinit_rcfw(&rdev->rcfw); if (rc) dev_warn(rdev_to_dev(rdev), "Failed to deinitialize RCFW: %#x", rc); - bnxt_re_net_stats_ctx_free(rdev, rdev->qplib_ctx.stats.fw_id, - lock_wait); + bnxt_re_net_stats_ctx_free(rdev, rdev->qplib_ctx.stats.fw_id); bnxt_qplib_free_ctx(rdev->en_dev->pdev, &rdev->qplib_ctx); bnxt_qplib_disable_rcfw_channel(&rdev->rcfw); - bnxt_re_net_ring_free(rdev, rdev->rcfw.creq_ring_id, lock_wait); + bnxt_re_net_ring_free(rdev, rdev->rcfw.creq_ring_id); bnxt_qplib_free_rcfw_channel(&rdev->rcfw); } if (test_and_clear_bit(BNXT_RE_FLAG_GOT_MSIX, &rdev->flags)) { - rc = bnxt_re_free_msix(rdev, lock_wait); + rc = bnxt_re_free_msix(rdev); if (rc) dev_warn(rdev_to_dev(rdev), "Failed to free MSI-X vectors: %#x", rc); } if (test_and_clear_bit(BNXT_RE_FLAG_NETDEV_REGISTERED, &rdev->flags)) { - rc = bnxt_re_unregister_netdev(rdev, lock_wait); + rc = bnxt_re_unregister_netdev(rdev); if (rc) dev_warn(rdev_to_dev(rdev), "Failed to unregister with netdev: %#x", rc); @@ -1276,6 +1243,12 @@ static int bnxt_re_ib_reg(struct bnxt_re_dev *rdev) { int i, j, rc; + bool locked; + + /* Acquire rtnl lock through out this function */ + rtnl_lock(); + locked = true; + /* Registered a new RoCE device instance to netdev */ rc = bnxt_re_register_netdev(rdev); if (rc) { @@ -1374,12 +1347,16 @@ static int bnxt_re_ib_reg(struct bnxt_re_dev *rdev) schedule_delayed_work(&rdev->worker, msecs_to_jiffies(30000)); } + rtnl_unlock(); + locked = false; + /* Register ib dev */ rc = bnxt_re_register_ib(rdev); if (rc) { pr_err("Failed to register with IB: %#x\n", rc); goto fail; } + set_bit(BNXT_RE_FLAG_IBDEV_REGISTERED, &rdev->flags); dev_info(rdev_to_dev(rdev), "Device registered successfully"); for (i = 0; i < ARRAY_SIZE(bnxt_re_attributes); i++) { rc = device_create_file(&rdev->ibdev.dev, @@ -1395,7 +1372,6 @@ static int bnxt_re_ib_reg(struct bnxt_re_dev *rdev) goto fail; } } - set_bit(BNXT_RE_FLAG_IBDEV_REGISTERED, &rdev->flags); ib_get_eth_speed(&rdev->ibdev, 1, &rdev->active_speed, &rdev->active_width); set_bit(BNXT_RE_FLAG_ISSUE_ROCE_STATS, &rdev->flags); @@ -1404,17 +1380,21 @@ static int bnxt_re_ib_reg(struct bnxt_re_dev *rdev) return 0; free_sctx: - bnxt_re_net_stats_ctx_free(rdev, rdev->qplib_ctx.stats.fw_id, true); + bnxt_re_net_stats_ctx_free(rdev, rdev->qplib_ctx.stats.fw_id); free_ctx: bnxt_qplib_free_ctx(rdev->en_dev->pdev, &rdev->qplib_ctx); disable_rcfw: bnxt_qplib_disable_rcfw_channel(&rdev->rcfw); free_ring: - bnxt_re_net_ring_free(rdev, rdev->rcfw.creq_ring_id, true); + bnxt_re_net_ring_free(rdev, rdev->rcfw.creq_ring_id); free_rcfw: bnxt_qplib_free_rcfw_channel(&rdev->rcfw); fail: - bnxt_re_ib_unreg(rdev, true); + if (!locked) + rtnl_lock(); + bnxt_re_ib_unreg(rdev); + rtnl_unlock(); + return rc; } @@ -1567,7 +1547,7 @@ static int bnxt_re_netdev_event(struct notifier_block *notifier, */ if (atomic_read(&rdev->sched_count) > 0) goto exit; - bnxt_re_ib_unreg(rdev, false); + bnxt_re_ib_unreg(rdev); bnxt_re_remove_one(rdev); bnxt_re_dev_unreg(rdev); break; @@ -1646,7 +1626,10 @@ static void __exit bnxt_re_mod_exit(void) */ flush_workqueue(bnxt_re_wq); bnxt_re_dev_stop(rdev); - bnxt_re_ib_unreg(rdev, true); + /* Acquire the rtnl_lock as the L2 resources are freed here */ + rtnl_lock(); + bnxt_re_ib_unreg(rdev); + rtnl_unlock(); bnxt_re_remove_one(rdev); bnxt_re_dev_unreg(rdev); } -- cgit v1.2.3-59-g8ed1b