6.12-stable review patch. If anyone has any objections, please let me know.
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From: Horatiu Vultur horatiu.vultur@microchip.com
[ 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 horatiu.vultur@microchip.com Reviewed-by: Jacob Keller jacob.e.keller@intel.com Link: https://patch.msgid.link/20251105074955.1766792-1-horatiu.vultur@microchip.c... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- .../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 2474dfd330f46..fe4e614052840 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] + @@ -416,7 +416,7 @@ 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[] = { @@ -442,7 +442,7 @@ 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] + @@ -500,7 +500,7 @@ 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; } @@ -603,7 +603,7 @@ 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]; @@ -685,7 +685,7 @@ 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) @@ -701,7 +701,7 @@ 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 b34e015eedf9b..b5dc65a4d6403 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c @@ -1262,7 +1262,6 @@ 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);
@@ -1280,7 +1279,6 @@ static void 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 8aa39497818fe..14484ea77cbed 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h @@ -295,8 +295,8 @@ 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 a1471e38d1189..2a37fc1ba4bcd 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,