From bd97a59da6a866e3dee5d2a2d582ec71dbbc84cd Mon Sep 17 00:00:00 2001 From: Shin'ichiro Kawasaki Date: Tue, 31 Jan 2023 18:26:44 +0900 Subject: [PATCH] nvme-auth: use workqueue dedicated to authentication NVMe In-Band authentication uses two kinds of works: chap->auth_work and ctrl->dhchap_auth_work. The latter work flushes or cancels the former work. However, the both works are queued to the same workqueue nvme-wq. It results in the lockdep WARNING as follows: WARNING: possible recursive locking detected 6.2.0-rc4+ #1 Not tainted -------------------------------------------- kworker/u16:7/69 is trying to acquire lock: ffff902d52e65548 ((wq_completion)nvme-wq){+.+.}-{0:0}, at: start_flush_work+0x2c5/0x380 but task is already holding lock: ffff902d52e65548 ((wq_completion)nvme-wq){+.+.}-{0:0}, at: process_one_work+0x210/0x410 To avoid the WARNING, introduce a new workqueue nvme-auth-wq dedicated to chap->auth_work. Reported-by: Daniel Wagner Link: https://lore.kernel.org/linux-nvme/20230130110802.paafkiipmitwtnwr@carbon.lan/ Fixes: f50fff73d620 ("nvme: implement In-Band authentication") Signed-off-by: Shin'ichiro Kawasaki Tested-by: Daniel Wagner Reviewed-by: Hannes Reinecke Signed-off-by: Christoph Hellwig --- drivers/nvme/host/auth.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/nvme/host/auth.c b/drivers/nvme/host/auth.c index 4424f53a8a0a..b57630d1d3b8 100644 --- a/drivers/nvme/host/auth.c +++ b/drivers/nvme/host/auth.c @@ -45,6 +45,8 @@ struct nvme_dhchap_queue_context { int sess_key_len; }; +struct workqueue_struct *nvme_auth_wq; + #define nvme_auth_flags_from_qid(qid) \ (qid == 0) ? 0 : BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_RESERVED #define nvme_auth_queue_from_qid(ctrl, qid) \ @@ -866,7 +868,7 @@ int nvme_auth_negotiate(struct nvme_ctrl *ctrl, int qid) chap = &ctrl->dhchap_ctxs[qid]; cancel_work_sync(&chap->auth_work); - queue_work(nvme_wq, &chap->auth_work); + queue_work(nvme_auth_wq, &chap->auth_work); return 0; } EXPORT_SYMBOL_GPL(nvme_auth_negotiate); @@ -1008,10 +1010,15 @@ EXPORT_SYMBOL_GPL(nvme_auth_free); int __init nvme_init_auth(void) { + nvme_auth_wq = alloc_workqueue("nvme-auth-wq", + WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS, 0); + if (!nvme_auth_wq) + return -ENOMEM; + nvme_chap_buf_cache = kmem_cache_create("nvme-chap-buf-cache", CHAP_BUF_SIZE, 0, SLAB_HWCACHE_ALIGN, NULL); if (!nvme_chap_buf_cache) - return -ENOMEM; + goto err_destroy_workqueue; nvme_chap_buf_pool = mempool_create(16, mempool_alloc_slab, mempool_free_slab, nvme_chap_buf_cache); @@ -1021,6 +1028,8 @@ int __init nvme_init_auth(void) return 0; err_destroy_chap_buf_cache: kmem_cache_destroy(nvme_chap_buf_cache); +err_destroy_workqueue: + destroy_workqueue(nvme_auth_wq); return -ENOMEM; } @@ -1028,4 +1037,5 @@ void __exit nvme_exit_auth(void) { mempool_destroy(nvme_chap_buf_pool); kmem_cache_destroy(nvme_chap_buf_cache); + destroy_workqueue(nvme_auth_wq); }