From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Baochen Qiang <quic_bqiang@quicinc.com>,
Kalle Valo <quic_kvalo@quicinc.com>,
Sasha Levin <sashal@kernel.org>,
kvalo@kernel.org, davem@davemloft.net, kuba@kernel.org,
ath11k@lists.infradead.org, linux-wireless@vger.kernel.org,
netdev@vger.kernel.org
Subject: [PATCH AUTOSEL 5.10 060/116] ath11k: Avoid false DEADLOCK warning reported by lockdep
Date: Mon, 17 Jan 2022 21:39:11 -0500 [thread overview]
Message-ID: <20220118024007.1950576-60-sashal@kernel.org> (raw)
In-Reply-To: <20220118024007.1950576-1-sashal@kernel.org>
From: Baochen Qiang <quic_bqiang@quicinc.com>
[ Upstream commit 767c94caf0efad136157110787fe221b74cb5c8a ]
With CONFIG_LOCKDEP=y and CONFIG_DEBUG_SPINLOCK=y, lockdep reports
below warning:
[ 166.059415] ============================================
[ 166.059416] WARNING: possible recursive locking detected
[ 166.059418] 5.15.0-wt-ath+ #10 Tainted: G W O
[ 166.059420] --------------------------------------------
[ 166.059421] kworker/0:2/116 is trying to acquire lock:
[ 166.059423] ffff9905f2083160 (&srng->lock){+.-.}-{2:2}, at: ath11k_hal_reo_cmd_send+0x20/0x490 [ath11k]
[ 166.059440]
but task is already holding lock:
[ 166.059442] ffff9905f2083230 (&srng->lock){+.-.}-{2:2}, at: ath11k_dp_process_reo_status+0x95/0x2d0 [ath11k]
[ 166.059491]
other info that might help us debug this:
[ 166.059492] Possible unsafe locking scenario:
[ 166.059493] CPU0
[ 166.059494] ----
[ 166.059495] lock(&srng->lock);
[ 166.059498] lock(&srng->lock);
[ 166.059500]
*** DEADLOCK ***
[ 166.059501] May be due to missing lock nesting notation
[ 166.059502] 3 locks held by kworker/0:2/116:
[ 166.059504] #0: ffff9905c0081548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1f6/0x660
[ 166.059511] #1: ffff9d2400a5fe68 ((debug_obj_work).work){+.+.}-{0:0}, at: process_one_work+0x1f6/0x660
[ 166.059517] #2: ffff9905f2083230 (&srng->lock){+.-.}-{2:2}, at: ath11k_dp_process_reo_status+0x95/0x2d0 [ath11k]
[ 166.059532]
stack backtrace:
[ 166.059534] CPU: 0 PID: 116 Comm: kworker/0:2 Kdump: loaded Tainted: G W O 5.15.0-wt-ath+ #10
[ 166.059537] Hardware name: Intel(R) Client Systems NUC8i7HVK/NUC8i7HVB, BIOS HNKBLi70.86A.0059.2019.1112.1124 11/12/2019
[ 166.059539] Workqueue: events free_obj_work
[ 166.059543] Call Trace:
[ 166.059545] <IRQ>
[ 166.059547] dump_stack_lvl+0x56/0x7b
[ 166.059552] __lock_acquire+0xb9a/0x1a50
[ 166.059556] lock_acquire+0x1e2/0x330
[ 166.059560] ? ath11k_hal_reo_cmd_send+0x20/0x490 [ath11k]
[ 166.059571] _raw_spin_lock_bh+0x33/0x70
[ 166.059574] ? ath11k_hal_reo_cmd_send+0x20/0x490 [ath11k]
[ 166.059584] ath11k_hal_reo_cmd_send+0x20/0x490 [ath11k]
[ 166.059594] ath11k_dp_tx_send_reo_cmd+0x3f/0x130 [ath11k]
[ 166.059605] ath11k_dp_rx_tid_del_func+0x221/0x370 [ath11k]
[ 166.059618] ath11k_dp_process_reo_status+0x22f/0x2d0 [ath11k]
[ 166.059632] ? ath11k_dp_service_srng+0x2ea/0x2f0 [ath11k]
[ 166.059643] ath11k_dp_service_srng+0x2ea/0x2f0 [ath11k]
[ 166.059655] ath11k_pci_ext_grp_napi_poll+0x1c/0x70 [ath11k_pci]
[ 166.059659] __napi_poll+0x28/0x230
[ 166.059664] net_rx_action+0x285/0x310
[ 166.059668] __do_softirq+0xe6/0x4d2
[ 166.059672] irq_exit_rcu+0xd2/0xf0
[ 166.059675] common_interrupt+0xa5/0xc0
[ 166.059678] </IRQ>
[ 166.059679] <TASK>
[ 166.059680] asm_common_interrupt+0x1e/0x40
[ 166.059683] RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70
[ 166.059686] Code: 83 c7 18 e8 2a 95 43 ff 48 89 ef e8 22 d2 43 ff 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 <e8> 63 2e 40 ff 65 8b 05 8c 59 97 5c 85 c0 74 0a 5b 5d c3 e8 00 6a
[ 166.059689] RSP: 0018:ffff9d2400a5fca0 EFLAGS: 00000206
[ 166.059692] RAX: 0000000000000002 RBX: 0000000000000200 RCX: 0000000000000006
[ 166.059694] RDX: 0000000000000000 RSI: ffffffffa404879b RDI: 0000000000000001
[ 166.059696] RBP: ffff9905c0053000 R08: 0000000000000001 R09: 0000000000000001
[ 166.059698] R10: ffff9d2400a5fc50 R11: 0000000000000001 R12: ffffe186c41e2840
[ 166.059700] R13: 0000000000000001 R14: ffff9905c78a1c68 R15: 0000000000000001
[ 166.059704] free_debug_processing+0x257/0x3d0
[ 166.059708] ? free_obj_work+0x1f5/0x250
[ 166.059712] __slab_free+0x374/0x5a0
[ 166.059718] ? kmem_cache_free+0x2e1/0x370
[ 166.059721] ? free_obj_work+0x1f5/0x250
[ 166.059724] kmem_cache_free+0x2e1/0x370
[ 166.059727] free_obj_work+0x1f5/0x250
[ 166.059731] process_one_work+0x28b/0x660
[ 166.059735] ? process_one_work+0x660/0x660
[ 166.059738] worker_thread+0x37/0x390
[ 166.059741] ? process_one_work+0x660/0x660
[ 166.059743] kthread+0x176/0x1a0
[ 166.059746] ? set_kthread_struct+0x40/0x40
[ 166.059749] ret_from_fork+0x22/0x30
[ 166.059754] </TASK>
Since these two lockes are both initialized in ath11k_hal_srng_setup,
they are assigned with the same key. As a result lockdep suspects that
the task is trying to acquire the same lock (due to same key) while
already holding it, and thus reports the DEADLOCK warning. However as
they are different spinlock instances, the warning is false positive.
On the other hand, even no dead lock indeed, this is a major issue for
upstream regression testing as it disables lockdep functionality.
Fix it by assigning separate lock class key for each srng->lock.
Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-01720.1-QCAHSPSWPL_V1_V2_SILICONZ_LITE-1
Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20211209011949.151472-1-quic_bqiang@quicinc.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/ath/ath11k/hal.c | 22 ++++++++++++++++++++++
drivers/net/wireless/ath/ath11k/hal.h | 2 ++
2 files changed, 24 insertions(+)
diff --git a/drivers/net/wireless/ath/ath11k/hal.c b/drivers/net/wireless/ath/ath11k/hal.c
index 9904c0eb75875..f3b9108ab6bd0 100644
--- a/drivers/net/wireless/ath/ath11k/hal.c
+++ b/drivers/net/wireless/ath/ath11k/hal.c
@@ -991,6 +991,7 @@ int ath11k_hal_srng_setup(struct ath11k_base *ab, enum hal_ring_type type,
srng->msi_data = params->msi_data;
srng->initialized = 1;
spin_lock_init(&srng->lock);
+ lockdep_set_class(&srng->lock, hal->srng_key + ring_id);
for (i = 0; i < HAL_SRNG_NUM_REG_GRP; i++) {
srng->hwreg_base[i] = srng_config->reg_start[i] +
@@ -1237,6 +1238,24 @@ static int ath11k_hal_srng_create_config(struct ath11k_base *ab)
return 0;
}
+static void ath11k_hal_register_srng_key(struct ath11k_base *ab)
+{
+ struct ath11k_hal *hal = &ab->hal;
+ u32 ring_id;
+
+ for (ring_id = 0; ring_id < HAL_SRNG_RING_ID_MAX; ring_id++)
+ lockdep_register_key(hal->srng_key + ring_id);
+}
+
+static void ath11k_hal_unregister_srng_key(struct ath11k_base *ab)
+{
+ struct ath11k_hal *hal = &ab->hal;
+ u32 ring_id;
+
+ for (ring_id = 0; ring_id < HAL_SRNG_RING_ID_MAX; ring_id++)
+ lockdep_unregister_key(hal->srng_key + ring_id);
+}
+
int ath11k_hal_srng_init(struct ath11k_base *ab)
{
struct ath11k_hal *hal = &ab->hal;
@@ -1256,6 +1275,8 @@ int ath11k_hal_srng_init(struct ath11k_base *ab)
if (ret)
goto err_free_cont_rdp;
+ ath11k_hal_register_srng_key(ab);
+
return 0;
err_free_cont_rdp:
@@ -1270,6 +1291,7 @@ void ath11k_hal_srng_deinit(struct ath11k_base *ab)
{
struct ath11k_hal *hal = &ab->hal;
+ ath11k_hal_unregister_srng_key(ab);
ath11k_hal_free_cont_rdp(ab);
ath11k_hal_free_cont_wrp(ab);
kfree(hal->srng_config);
diff --git a/drivers/net/wireless/ath/ath11k/hal.h b/drivers/net/wireless/ath/ath11k/hal.h
index 1f1b29cd0aa39..5fbfded8d546c 100644
--- a/drivers/net/wireless/ath/ath11k/hal.h
+++ b/drivers/net/wireless/ath/ath11k/hal.h
@@ -888,6 +888,8 @@ struct ath11k_hal {
/* shadow register configuration */
u32 shadow_reg_addr[HAL_SHADOW_NUM_REGS];
int num_shadow_reg_configured;
+
+ struct lock_class_key srng_key[HAL_SRNG_RING_ID_MAX];
};
u32 ath11k_hal_reo_qdesc_size(u32 ba_window_size, u8 tid);
--
2.34.1
next prev parent reply other threads:[~2022-01-18 2:54 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20220118024007.1950576-1-sashal@kernel.org>
2022-01-18 2:38 ` [PATCH AUTOSEL 5.10 006/116] ar5523: Fix null-ptr-deref with unexpected WDCMSG_TARGET_START reply Sasha Levin
2022-01-18 2:38 ` [PATCH AUTOSEL 5.10 015/116] ath11k: Fix crash caused by uninitialized TX ring Sasha Levin
2022-01-18 2:38 ` [PATCH AUTOSEL 5.10 031/116] mwifiex: Fix skb_over_panic in mwifiex_usb_recv() Sasha Levin
2022-01-18 2:38 ` [PATCH AUTOSEL 5.10 032/116] rsi: Fix use-after-free in rsi_rx_done_handler() Sasha Levin
2022-01-18 2:38 ` [PATCH AUTOSEL 5.10 033/116] rsi: Fix out-of-bounds read in rsi_read_pkt() Sasha Levin
2022-01-18 2:38 ` [PATCH AUTOSEL 5.10 034/116] ath11k: Avoid NULL ptr access during mgmt tx cleanup Sasha Levin
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 050/116] iwlwifi: mvm: synchronize with FW after multicast commands Sasha Levin
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 051/116] iwlwifi: mvm: avoid clearing a just saved session protection id Sasha Levin
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 053/116] ath11k: avoid deadlock by change ieee80211_queue_work for regd_update_work Sasha Levin
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 054/116] ath10k: Fix tx hanging Sasha Levin
2022-01-18 2:39 ` Sasha Levin [this message]
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 077/116] ath9k: Fix out-of-bound memcpy in ath9k_hif_usb_rx_stream Sasha Levin
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 078/116] rtw88: 8822c: update rx settings to prevent potential hw deadlock Sasha Levin
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 080/116] iwlwifi: fix leaks/bad data after failed firmware load Sasha Levin
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 081/116] iwlwifi: remove module loading failure message Sasha Levin
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 082/116] iwlwifi: mvm: Fix calculation of frame length Sasha Levin
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 083/116] iwlwifi: pcie: make sure prph_info is set when treating wakeup IRQ Sasha Levin
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 085/116] ath11k: Fix napi related hang Sasha Levin
2022-01-18 2:39 ` [PATCH AUTOSEL 5.10 102/116] mac80211: allow non-standard VHT MCS-10/11 Sasha Levin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220118024007.1950576-60-sashal@kernel.org \
--to=sashal@kernel.org \
--cc=ath11k@lists.infradead.org \
--cc=davem@davemloft.net \
--cc=kuba@kernel.org \
--cc=kvalo@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-wireless@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=quic_bqiang@quicinc.com \
--cc=quic_kvalo@quicinc.com \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).