The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

Possible dependencies:

bd97a59da6a8 ("nvme-auth: use workqueue dedicated to authentication") aa36d711e945 ("nvme-auth: convert dhchap_auth_list to an array") 8d1c1904e947 ("nvme-auth: clear sensitive info right after authentication completes") e481fc0a3777 ("nvme-auth: guarantee dhchap buffers under memory pressure") b7d604cae8f6 ("nvme-auth: don't keep long lived 4k dhchap buffer") bfc4068e1e55 ("nvme-auth: remove redundant if statement") 01604350e145 ("nvme-auth: don't override ctrl keys before validation") 193a8c7e5f1a ("nvme-auth: don't ignore key generation failures when initializing ctrl keys") f6b182fbd5c6 ("nvme-auth: remove redundant buffer deallocations") 0c999e69c40a ("nvme-auth: rename authentication work elements") 0a7ce375f83f ("nvme-auth: rename __nvme_auth_[reset|free] to nvme_auth[reset|free]_dhchap")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From bd97a59da6a866e3dee5d2a2d582ec71dbbc84cd Mon Sep 17 00:00:00 2001 From: Shin'ichiro Kawasaki shinichiro.kawasaki@wdc.com 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 dwagner@suse.de Link: https://lore.kernel.org/linux-nvme/20230130110802.paafkiipmitwtnwr@carbon.la... Fixes: f50fff73d620 ("nvme: implement In-Band authentication") Signed-off-by: Shin'ichiro Kawasaki shinichiro.kawasaki@wdc.com Tested-by: Daniel Wagner dwagner@suse.de Reviewed-by: Hannes Reinecke hare@suse.de Signed-off-by: Christoph Hellwig hch@lst.de

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); }