lwn.git/drivers/net/ethernet/smsc/smc91x.c, branch docs-mw

smc91x: fix broken irq-context in PREEMPT_RT

2025-12-23T14:28:34+00:00

When smc91x.c is built with PREEMPT_RT, the following splat occurs in FVP_RevC: [ 13.055000] smc91x LNRO0003:00 eth0: link up, 10Mbps, half-duplex, lpa 0x0000 [ 13.062137] BUG: workqueue leaked atomic, lock or RCU: kworker/2:1[106] [ 13.062137] preempt=0x00000000 lock=0->0 RCU=0->1 workfn=mld_ifc_work [ 13.062266] C ** replaying previous printk message ** [ 13.062266] CPU: 2 UID: 0 PID: 106 Comm: kworker/2:1 Not tainted 6.18.0-dirty #179 PREEMPT_{RT,(full)} [ 13.062353] Hardware name: , BIOS [ 13.062382] Workqueue: mld mld_ifc_work [ 13.062469] Call trace: [ 13.062494] show_stack+0x24/0x40 (C) [ 13.062602] __dump_stack+0x28/0x48 [ 13.062710] dump_stack_lvl+0x7c/0xb0 [ 13.062818] dump_stack+0x18/0x34 [ 13.062926] process_scheduled_works+0x294/0x450 [ 13.063043] worker_thread+0x260/0x3d8 [ 13.063124] kthread+0x1c4/0x228 [ 13.063235] ret_from_fork+0x10/0x20 This happens because smc_special_trylock() disables IRQs even on PREEMPT_RT, but smc_special_unlock() does not restore IRQs on PREEMPT_RT. The reason is that smc_special_unlock() calls spin_unlock_irqrestore(), and rcu_read_unlock_bh() in __dev_queue_xmit() cannot invoke rcu_read_unlock() through __local_bh_enable_ip() when current->softirq_disable_cnt becomes zero. To address this issue, replace smc_special_trylock() with spin_trylock_irqsave(). Fixes: 342a93247e08 ("locking/spinlock: Provide RT variant header: ") Signed-off-by: Yeoreum Yun Reviewed-by: Simon Horman Link: https://patch.msgid.link/20251217085115.1730036-1-yeoreum.yun@arm.com Signed-off-by: Paolo Abeni

net: ethernet: Switch back to struct platform_driver::remove()

2024-10-04T23:39:56+00:00

After commit 0edb555a65d1 ("platform: Make platform_driver::remove() return void") .remove() is (again) the right callback to implement for platform drivers. Convert all platform drivers below drivers/net/ethernet to use .remove(), with the eventual goal to drop struct platform_driver::remove_new(). As .remove() and .remove_new() have the same prototypes, conversion is done by just changing the structure member name in the driver initializer. Signed-off-by: Uwe Kleine-König Link: https://patch.msgid.link/18f7c585a1a8a8ac8b03a2fca7de19bd5c52ac2b.1727949050.git.u.kleine-koenig@baylibre.com Signed-off-by: Jakub Kicinski

net: smc91x: Make use of irq_get_trigger_type()

2024-09-07T01:21:43+00:00

Convert irqd_get_trigger_type(irq_get_irq_data(irq)) cases to the more simple irq_get_trigger_type(irq). Signed-off-by: Vasileios Amoiridis Reviewed-by: Alvin Šipraga Link: https://patch.msgid.link/20240904151018.71967-4-vassilisamir@gmail.com Signed-off-by: Jakub Kicinski

net: smc91x: Remove commented out code

2024-05-30T01:42:22+00:00

Remove commented out code Signed-off-by: Thorsten Blum Link: https://lore.kernel.org/r/20240528160036.404946-2-thorsten.blum@toblux.com Signed-off-by: Jakub Kicinski

net: fill in MODULE_DESCRIPTION()s for SMSC drivers

2024-01-29T12:12:51+00:00

W=1 builds now warn if module is built without a MODULE_DESCRIPTION(). Add descriptions to the SMSC 91x/911x/9420 Ethernet drivers. Signed-off-by: Breno Leitao Signed-off-by: David S. Miller

net: ethernet: smsc: Convert to platform remove callback returning void

2023-09-20T08:06:40+00:00

The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is ignored (apart from emitting a warning) and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new() which already returns void. Eventually after all drivers are converted, .remove_new() is renamed to .remove(). Trivially convert these drivers from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König Signed-off-by: David S. Miller

net: smc91x: Replace of_gpio.h with what indeed is used

2023-03-19T10:40:04+00:00

of_gpio.h in this driver is solely used as a proxy to other headers. This is incorrect usage of the of_gpio.h. Replace it .h with what indeed is used in the code. Signed-off-by: Andy Shevchenko Signed-off-by: David S. Miller

net: ethernet: move from strlcpy with unused retval to strscpy

2022-08-31T21:11:26+00:00

Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang Reviewed-by: Petr Machata # For drivers/net/ethernet/mellanox/mlxsw Acked-by: Geoff Levand # For ps3_gelic_net and spider_net_ethtool Acked-by: Tom Lendacky # For drivers/net/ethernet/amd/xgbe/xgbe-ethtool.c Acked-by: Marcin Wojtas # For drivers/net/ethernet/marvell/mvpp2 Reviewed-by: Leon Romanovsky # For drivers/net/ethernet/mellanox/mlx{4|5} Reviewed-by: Shay Agroskin # For drivers/net/ethernet/amazon/ena Acked-by: Krzysztof Hałasa # For IXP4xx Ethernet Link: https://lore.kernel.org/r/20220830201457.7984-3-wsa+renesas@sang-engineering.com Signed-off-by: Jakub Kicinski

ethernet: smc91x: use eth_hw_addr_set()

2021-10-19T11:41:48+00:00

Commit 406f42fa0d3c ("net-next: When a bond have a massive amount of VLANs...") introduced a rbtree for faster Ethernet address look up. To maintain netdev->dev_addr in this tree we need to make all the writes to it got through appropriate helpers. Read the address into an array on the stack, then call eth_hw_addr_set(). Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

net: smsc: remove leading spaces before tabs

2021-05-19T19:17:31+00:00

There are a few leading spaces before tabs and remove it by running the following commard: $ find . -name '*.c' | xargs sed -r -i 's/^[ ]+\t/\t/' $ find . -name '*.h' | xargs sed -r -i 's/^[ ]+\t/\t/' Cc: Andrew Lunn Signed-off-by: Hui Tang Signed-off-by: David S. Miller