From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793214542; b=m63xH7tli6JkENiW9D4jbIMoQ2GvwBqa6d2ThdfP85S859UNAy3wmzqN6d7tJEPPZY7r +mwU0/1z34sip6OROP/lHNTjznc1hbTAQduRO5Xzx4dWYwo2b6wsZ+PtuQ+sOTHRApVp6 dKpwR9BCrxMEIY4IrVFpFB651MI/r8qjmA1prjtI6d81oLjkrRuW9lYaxQlgkdO1ItLiQ O/xhR/PYvVjb0eNMg4z2Ja5XMstQi31Fs2+1L753/Xsa8rGBxTWAwrgYEw5da/vRiuLGJ 1uVRNEGemgeycWSCeWzq3GvMkhy18RhVcSayGrFHaIkkTxEalYMJ6yISMUR6oDnxlYQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793214542; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=dVltU4hgDWHYmWrfsMnAc4frWZ1cXUlfT3dszolZp7U=; b=gY4I5QkHDNCvi38to2lPPYKpULNM23t8sZ27ojN/gU9DkMeZUPpw1cNaFhLc35Uxr2Qw pofOGehaoAse/hlejR7UxKMxdcf1fkBDquuVwxRRgGMGBj9VDv3czb7bUkrS+EW6t5rep EUIzQDPdGBgdf4evFz8wY+I8YxnM3VSzs/OY6QuR6Yod3OsKN6a+wPNUeOX7udx4IXbwg KqH6Wy8bqGOCwr3JbW4QAMz+tUsxvfIMOJwVfTuEwqcyYQIWZYghxDNFGaKauY6UhqyT7 +0enDOVLV77XEExWMUf880APrQ3yjfUPJohjPcGiFFnbAGlALa89bvrBpwrnnsXhLPg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=OXWjULu0; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 53B7860A2607; Wed, 28 Oct 2026 19:09:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=OXWjULu0 Received: by smtp.kernel.org (Postfix) with ESMTPSA id A32811F01825; Wed, 28 Oct 2026 19:09:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793214541; bh=dVltU4hgDWHYmWrfsMnAc4frWZ1cXUlfT3dszolZp7U=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=OXWjULu0hvtXy0t2xCzLWaJy5iEhXD9rVWXyrj1dXhn2NNEc90OqFXCHF4qGTgnE4 60Xz6YZJyNdeknaFQ/PGinUjePwA9LYR86R30NRX3jjrRWGe1hh0qKiw4OQJ06NfZX nmJzRCFHIohpsZo/HubnGNg0cD5tRzZDjAsg7ttM= 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 6.1 0893/1887] lan966x: Fix sleeping in atomic context Date: Wed, 28 Oct 2026 17:49:49 +0100 Message-ID: <20261028170519.739400984@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170459.200466217@linuxfoundation.org> References: <20261028170459.200466217@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-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 ++-- 3 files changed, 11 insertions(+), 13 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 8347def40f9d4..4a85cd5ebcce0 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c @@ -1182,7 +1182,6 @@ 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); return err; } @@ -1197,7 +1196,6 @@ 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 ff5736d2c7a6b..3f8b724eac47e 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h @@ -231,8 +231,8 @@ 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; -- 2.53.0