From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ED6AA33F38B; Fri, 21 Nov 2025 13:51:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763733118; cv=none; b=OxNU1g6CwzDJCwTTonJrQt2Z3AO/hDqqz8xCAt0QtMVzY+eFSwSOJuy75p5EVUreIeHpdPDYrsOmK/pkjS0viIxKoTq8e8kFTvKUvYqREgDWgMaf7jTWOFWMhNxIMO4J6WQzyEIGuVEbL+pWKfAXqgFPjfacud8uJRynAPl8Twc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763733118; c=relaxed/simple; bh=4KtKzydnq9QX2SAt7LVVyP9ucfk7MSNQfRFEJBK7udU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=E2yxn6JR3rWH7K95jL+XC6Oox2jK/h7A5AsQ0/qJ5cnfsL4u8muS+Yg0SZFEQl5WTDeNdqmQOuYyJ8NElP5cYurRfAPs8IBU1KmqwS4RxVFFVT2JmfxBsSJw+j+Se9Rbbsaq7SP9QoTzTPLHF8fXD3pACQaWDl+/23orP4vGcWQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=YR1Nyovj; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="YR1Nyovj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 76C16C4CEF1; Fri, 21 Nov 2025 13:51:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1763733117; bh=4KtKzydnq9QX2SAt7LVVyP9ucfk7MSNQfRFEJBK7udU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YR1NyovjNpv7JD9wnKTfKGCjfDp+0b1ke9r4naYXz9NblfDfTKi3gdPc5hZmAz3Hm YeKwhtli8Eu7LuZMhQRDw2Yv9f2onEuwRsEHv42jqDCc1XL+456EDCOlSC4MRFzns1 HJ+RywUuG37LmRBwpt5c6wqnvZP/5ASxQ/cfVzIc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Horatiu Vultur , Jacob Keller , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.6 358/529] lan966x: Fix sleeping in atomic context Date: Fri, 21 Nov 2025 14:10:57 +0100 Message-ID: <20251121130243.766546554@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251121130230.985163914@linuxfoundation.org> References: <20251121130230.985163914@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Horatiu Vultur [ Upstream commit 0216721ce71252f60d89af49c8dff613358058d3 ] The following warning was seen when we try to connect using ssh to the device. BUG: sleeping function called from invalid context at kernel/locking/mutex.c:575 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 104, name: dropbear preempt_count: 1, expected: 0 INFO: lockdep is turned off. CPU: 0 UID: 0 PID: 104 Comm: dropbear Tainted: G W 6.18.0-rc2-00399-g6f1ab1b109b9-dirty #530 NONE Tainted: [W]=WARN Hardware name: Generic DT based system Call trace: unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x7c/0xac dump_stack_lvl from __might_resched+0x16c/0x2b0 __might_resched from __mutex_lock+0x64/0xd34 __mutex_lock from mutex_lock_nested+0x1c/0x24 mutex_lock_nested from lan966x_stats_get+0x5c/0x558 lan966x_stats_get from dev_get_stats+0x40/0x43c dev_get_stats from dev_seq_printf_stats+0x3c/0x184 dev_seq_printf_stats from dev_seq_show+0x10/0x30 dev_seq_show from seq_read_iter+0x350/0x4ec seq_read_iter from seq_read+0xfc/0x194 seq_read from proc_reg_read+0xac/0x100 proc_reg_read from vfs_read+0xb0/0x2b0 vfs_read from ksys_read+0x6c/0xec ksys_read from ret_fast_syscall+0x0/0x1c Exception stack(0xf0b11fa8 to 0xf0b11ff0) 1fa0: 00000001 00001000 00000008 be9048d8 00001000 00000001 1fc0: 00000001 00001000 00000008 00000003 be905920 0000001e 00000000 00000001 1fe0: 0005404c be9048c0 00018684 b6ec2cd8 It seems that we are using a mutex in a atomic context which is wrong. Change the mutex with a spinlock. Fixes: 12c2d0a5b8e2 ("net: lan966x: add ethtool configuration and statistics") Signed-off-by: Horatiu Vultur Reviewed-by: Jacob Keller Link: https://patch.msgid.link/20251105074955.1766792-1-horatiu.vultur@microchip.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- .../microchip/lan966x/lan966x_ethtool.c | 18 +++++++++--------- .../ethernet/microchip/lan966x/lan966x_main.c | 2 -- .../ethernet/microchip/lan966x/lan966x_main.h | 4 ++-- .../microchip/lan966x/lan966x_vcap_impl.c | 8 ++++---- 4 files changed, 15 insertions(+), 17 deletions(-) diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_ethtool.c b/drivers/net/ethernet/microchip/lan966x/lan966x_ethtool.c index 06811c60d598e..df10a0b68a08e 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_ethtool.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_ethtool.c @@ -294,7 +294,7 @@ static void lan966x_stats_update(struct lan966x *lan966x) { int i, j; - mutex_lock(&lan966x->stats_lock); + spin_lock(&lan966x->stats_lock); for (i = 0; i < lan966x->num_phys_ports; i++) { uint idx = i * lan966x->num_stats; @@ -310,7 +310,7 @@ static void lan966x_stats_update(struct lan966x *lan966x) } } - mutex_unlock(&lan966x->stats_lock); + spin_unlock(&lan966x->stats_lock); } static int lan966x_get_sset_count(struct net_device *dev, int sset) @@ -365,7 +365,7 @@ static void lan966x_get_eth_mac_stats(struct net_device *dev, idx = port->chip_port * lan966x->num_stats; - mutex_lock(&lan966x->stats_lock); + spin_lock(&lan966x->stats_lock); mac_stats->FramesTransmittedOK = lan966x->stats[idx + SYS_COUNT_TX_UC] + @@ -424,7 +424,7 @@ static void lan966x_get_eth_mac_stats(struct net_device *dev, lan966x->stats[idx + SYS_COUNT_RX_LONG] + lan966x->stats[idx + SYS_COUNT_RX_PMAC_LONG]; - mutex_unlock(&lan966x->stats_lock); + spin_unlock(&lan966x->stats_lock); } static const struct ethtool_rmon_hist_range lan966x_rmon_ranges[] = { @@ -450,7 +450,7 @@ static void lan966x_get_eth_rmon_stats(struct net_device *dev, idx = port->chip_port * lan966x->num_stats; - mutex_lock(&lan966x->stats_lock); + spin_lock(&lan966x->stats_lock); rmon_stats->undersize_pkts = lan966x->stats[idx + SYS_COUNT_RX_SHORT] + @@ -508,7 +508,7 @@ static void lan966x_get_eth_rmon_stats(struct net_device *dev, lan966x->stats[idx + SYS_COUNT_TX_SZ_1024_1526] + lan966x->stats[idx + SYS_COUNT_TX_PMAC_SZ_1024_1526]; - mutex_unlock(&lan966x->stats_lock); + spin_unlock(&lan966x->stats_lock); *ranges = lan966x_rmon_ranges; } @@ -614,7 +614,7 @@ void lan966x_stats_get(struct net_device *dev, idx = port->chip_port * lan966x->num_stats; - mutex_lock(&lan966x->stats_lock); + spin_lock(&lan966x->stats_lock); stats->rx_bytes = lan966x->stats[idx + SYS_COUNT_RX_OCT] + lan966x->stats[idx + SYS_COUNT_RX_PMAC_OCT]; @@ -696,7 +696,7 @@ void lan966x_stats_get(struct net_device *dev, stats->collisions = lan966x->stats[idx + SYS_COUNT_TX_COL]; - mutex_unlock(&lan966x->stats_lock); + spin_unlock(&lan966x->stats_lock); } int lan966x_stats_init(struct lan966x *lan966x) @@ -712,7 +712,7 @@ int lan966x_stats_init(struct lan966x *lan966x) return -ENOMEM; /* Init stats worker */ - mutex_init(&lan966x->stats_lock); + spin_lock_init(&lan966x->stats_lock); snprintf(queue_name, sizeof(queue_name), "%s-stats", dev_name(lan966x->dev)); lan966x->stats_queue = create_singlethread_workqueue(queue_name); diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c index b424e75fd40c4..5466f14e000ce 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c @@ -1263,7 +1263,6 @@ static int lan966x_probe(struct platform_device *pdev) cancel_delayed_work_sync(&lan966x->stats_work); destroy_workqueue(lan966x->stats_queue); - mutex_destroy(&lan966x->stats_lock); debugfs_remove_recursive(lan966x->debugfs_root); @@ -1281,7 +1280,6 @@ static int lan966x_remove(struct platform_device *pdev) cancel_delayed_work_sync(&lan966x->stats_work); destroy_workqueue(lan966x->stats_queue); - mutex_destroy(&lan966x->stats_lock); lan966x_mac_purge_entries(lan966x); lan966x_mdb_deinit(lan966x); diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h index 5a16d76eb000d..1f5a18b205bf2 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h @@ -347,8 +347,8 @@ struct lan966x { const struct lan966x_stat_layout *stats_layout; u32 num_stats; - /* workqueue for reading stats */ - struct mutex stats_lock; + /* lock for reading stats */ + spinlock_t stats_lock; u64 *stats; struct delayed_work stats_work; struct workqueue_struct *stats_queue; diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_vcap_impl.c b/drivers/net/ethernet/microchip/lan966x/lan966x_vcap_impl.c index a4414f63c9b1c..c266f903ea8a6 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_vcap_impl.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_vcap_impl.c @@ -403,11 +403,11 @@ static void lan966x_es0_read_esdx_counter(struct lan966x *lan966x, u32 counter; id = id & 0xff; /* counter limit */ - mutex_lock(&lan966x->stats_lock); + spin_lock(&lan966x->stats_lock); lan_wr(SYS_STAT_CFG_STAT_VIEW_SET(id), lan966x, SYS_STAT_CFG); counter = lan_rd(lan966x, SYS_CNT(LAN966X_STAT_ESDX_GRN_PKTS)) + lan_rd(lan966x, SYS_CNT(LAN966X_STAT_ESDX_YEL_PKTS)); - mutex_unlock(&lan966x->stats_lock); + spin_unlock(&lan966x->stats_lock); if (counter) admin->cache.counter = counter; } @@ -417,14 +417,14 @@ static void lan966x_es0_write_esdx_counter(struct lan966x *lan966x, { id = id & 0xff; /* counter limit */ - mutex_lock(&lan966x->stats_lock); + spin_lock(&lan966x->stats_lock); lan_wr(SYS_STAT_CFG_STAT_VIEW_SET(id), lan966x, SYS_STAT_CFG); lan_wr(0, lan966x, SYS_CNT(LAN966X_STAT_ESDX_GRN_BYTES)); lan_wr(admin->cache.counter, lan966x, SYS_CNT(LAN966X_STAT_ESDX_GRN_PKTS)); lan_wr(0, lan966x, SYS_CNT(LAN966X_STAT_ESDX_YEL_BYTES)); lan_wr(0, lan966x, SYS_CNT(LAN966X_STAT_ESDX_YEL_PKTS)); - mutex_unlock(&lan966x->stats_lock); + spin_unlock(&lan966x->stats_lock); } static void lan966x_vcap_cache_write(struct net_device *dev, -- 2.51.0