2019-10-25 20:21:47

by Jiangfeng Xiao

[permalink] [raw]
Subject: [PATCH] net: hisilicon: Fix "Trying to free already-free IRQ"

When rmmod hip04_eth.ko, we can get the following warning:

Task track: rmmod(1623)>bash(1591)>login(1581)>init(1)
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1623 at kernel/irq/manage.c:1557 __free_irq+0xa4/0x2ac()
Trying to free already-free IRQ 200
Modules linked in: ping(O) pramdisk(O) cpuinfo(O) rtos_snapshot(O) interrupt_ctrl(O) mtdblock mtd_blkdevrtfs nfs_acl nfs lockd grace sunrpc xt_tcpudp ipt_REJECT iptable_filter ip_tables x_tables nf_reject_ipv
CPU: 0 PID: 1623 Comm: rmmod Tainted: G O 4.4.193 #1
Hardware name: Hisilicon A15
[<c020b408>] (rtos_unwind_backtrace) from [<c0206624>] (show_stack+0x10/0x14)
[<c0206624>] (show_stack) from [<c03f2be4>] (dump_stack+0xa0/0xd8)
[<c03f2be4>] (dump_stack) from [<c021a780>] (warn_slowpath_common+0x84/0xb0)
[<c021a780>] (warn_slowpath_common) from [<c021a7e8>] (warn_slowpath_fmt+0x3c/0x68)
[<c021a7e8>] (warn_slowpath_fmt) from [<c026876c>] (__free_irq+0xa4/0x2ac)
[<c026876c>] (__free_irq) from [<c0268a14>] (free_irq+0x60/0x7c)
[<c0268a14>] (free_irq) from [<c0469e80>] (release_nodes+0x1c4/0x1ec)
[<c0469e80>] (release_nodes) from [<c0466924>] (__device_release_driver+0xa8/0x104)
[<c0466924>] (__device_release_driver) from [<c0466a80>] (driver_detach+0xd0/0xf8)
[<c0466a80>] (driver_detach) from [<c0465e18>] (bus_remove_driver+0x64/0x8c)
[<c0465e18>] (bus_remove_driver) from [<c02935b0>] (SyS_delete_module+0x198/0x1e0)
[<c02935b0>] (SyS_delete_module) from [<c0202ed0>] (__sys_trace_return+0x0/0x10)
---[ end trace bb25d6123d849b44 ]---

Currently "rmmod hip04_eth.ko" call free_irq more than once
as devres_release_all and hip04_remove both call free_irq.
This results in a 'Trying to free already-free IRQ' warning.
To solve the problem free_irq has been moved out of hip04_remove.

Signed-off-by: Jiangfeng Xiao <[email protected]>
---
drivers/net/ethernet/hisilicon/hip04_eth.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/net/ethernet/hisilicon/hip04_eth.c b/drivers/net/ethernet/hisilicon/hip04_eth.c
index c841674..ad6d912 100644
--- a/drivers/net/ethernet/hisilicon/hip04_eth.c
+++ b/drivers/net/ethernet/hisilicon/hip04_eth.c
@@ -1038,7 +1038,6 @@ static int hip04_remove(struct platform_device *pdev)

hip04_free_ring(ndev, d);
unregister_netdev(ndev);
- free_irq(ndev->irq, ndev);
of_node_put(priv->phy_node);
cancel_work_sync(&priv->tx_timeout_task);
free_netdev(ndev);
--
1.8.5.6


2019-10-29 19:58:36

by David Miller

[permalink] [raw]
Subject: Re: [PATCH] net: hisilicon: Fix "Trying to free already-free IRQ"

From: Jiangfeng Xiao <[email protected]>
Date: Fri, 25 Oct 2019 21:48:22 +0800

> When rmmod hip04_eth.ko, we can get the following warning:
...
> Currently "rmmod hip04_eth.ko" call free_irq more than once
> as devres_release_all and hip04_remove both call free_irq.
> This results in a 'Trying to free already-free IRQ' warning.
> To solve the problem free_irq has been moved out of hip04_remove.
>
> Signed-off-by: Jiangfeng Xiao <[email protected]>

Applied, thank you.