2023-08-31 15:54:59

by Remi Pommarel

[permalink] [raw]
Subject: [PATCH net] net: stmmac: remove unneeded stmmac_poll_controller

Using netconsole netpoll_poll_dev could be called from interrupt
context, thus using disable_irq() would cause the following kernel
warning with CONFIG_DEBUG_ATOMIC_SLEEP enabled:

BUG: sleeping function called from invalid context at kernel/irq/manage.c:137
in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 10, name: ksoftirqd/0
CPU: 0 PID: 10 Comm: ksoftirqd/0 Tainted: G W 5.15.42-00075-g816b502b2298-dirty #117
Hardware name: aml (r1) (DT)
Call trace:
dump_backtrace+0x0/0x270
show_stack+0x14/0x20
dump_stack_lvl+0x8c/0xac
dump_stack+0x18/0x30
___might_sleep+0x150/0x194
__might_sleep+0x64/0xbc
synchronize_irq+0x8c/0x150
disable_irq+0x2c/0x40
stmmac_poll_controller+0x140/0x1a0
netpoll_poll_dev+0x6c/0x220
netpoll_send_skb+0x308/0x390
netpoll_send_udp+0x418/0x760
write_msg+0x118/0x140 [netconsole]
console_unlock+0x404/0x500
vprintk_emit+0x118/0x250
dev_vprintk_emit+0x19c/0x1cc
dev_printk_emit+0x90/0xa8
__dev_printk+0x78/0x9c
_dev_warn+0xa4/0xbc
ath10k_warn+0xe8/0xf0 [ath10k_core]
ath10k_htt_txrx_compl_task+0x790/0x7fc [ath10k_core]
ath10k_pci_napi_poll+0x98/0x1f4 [ath10k_pci]
__napi_poll+0x58/0x1f4
net_rx_action+0x504/0x590
_stext+0x1b8/0x418
run_ksoftirqd+0x74/0xa4
smpboot_thread_fn+0x210/0x3c0
kthread+0x1fc/0x210
ret_from_fork+0x10/0x20

Since [0] .ndo_poll_controller is only needed if driver doesn't or
partially use NAPI. Because stmmac does so, stmmac_poll_controller
can be removed fixing the above warning.

[0] commit ac3d9dd034e5 ("netpoll: make ndo_poll_controller() optional")

Cc: <[email protected]> # 5.15.x
Signed-off-by: Remi Pommarel <[email protected]>
---
.../net/ethernet/stmicro/stmmac/stmmac_main.c | 30 -------------------
1 file changed, 30 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 4727f7be4f86..9b5c0ebf0519 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -5938,33 +5938,6 @@ static irqreturn_t stmmac_msi_intr_rx(int irq, void *data)
return IRQ_HANDLED;
}

-#ifdef CONFIG_NET_POLL_CONTROLLER
-/* Polling receive - used by NETCONSOLE and other diagnostic tools
- * to allow network I/O with interrupts disabled.
- */
-static void stmmac_poll_controller(struct net_device *dev)
-{
- struct stmmac_priv *priv = netdev_priv(dev);
- int i;
-
- /* If adapter is down, do nothing */
- if (test_bit(STMMAC_DOWN, &priv->state))
- return;
-
- if (priv->plat->multi_msi_en) {
- for (i = 0; i < priv->plat->rx_queues_to_use; i++)
- stmmac_msi_intr_rx(0, &priv->dma_conf.rx_queue[i]);
-
- for (i = 0; i < priv->plat->tx_queues_to_use; i++)
- stmmac_msi_intr_tx(0, &priv->dma_conf.tx_queue[i]);
- } else {
- disable_irq(dev->irq);
- stmmac_interrupt(dev->irq, dev);
- enable_irq(dev->irq);
- }
-}
-#endif
-
/**
* stmmac_ioctl - Entry point for the Ioctl
* @dev: Device pointer.
@@ -6800,9 +6773,6 @@ static const struct net_device_ops stmmac_netdev_ops = {
.ndo_eth_ioctl = stmmac_ioctl,
.ndo_setup_tc = stmmac_setup_tc,
.ndo_select_queue = stmmac_select_queue,
-#ifdef CONFIG_NET_POLL_CONTROLLER
- .ndo_poll_controller = stmmac_poll_controller,
-#endif
.ndo_set_mac_address = stmmac_set_mac_address,
.ndo_vlan_rx_add_vid = stmmac_vlan_rx_add_vid,
.ndo_vlan_rx_kill_vid = stmmac_vlan_rx_kill_vid,
--
2.40.0



2023-09-06 06:59:52

by Jakub Kicinski

[permalink] [raw]
Subject: Re: [PATCH net] net: stmmac: remove unneeded stmmac_poll_controller

On Thu, 31 Aug 2023 14:00:04 +0200 Remi Pommarel wrote:
> Using netconsole netpoll_poll_dev could be called from interrupt
> context, thus using disable_irq() would cause the following kernel
> warning with CONFIG_DEBUG_ATOMIC_SLEEP enabled:

Could you rebase this on top of netdev/net? It does not apply:

Failed to apply patch:
Applying: net: stmmac: remove unneeded stmmac_poll_controller
Using index info to reconstruct a base tree...
M drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
Falling back to patching base and 3-way merge...
Auto-merging drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
CONFLICT (content): Merge conflict in drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
Recorded preimage for 'drivers/net/ethernet/stmicro/stmmac/stmmac_main.c'
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0001 net: stmmac: remove unneeded stmmac_poll_controller
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

2023-09-06 09:42:26

by Remi Pommarel

[permalink] [raw]
Subject: Re: [PATCH net] net: stmmac: remove unneeded stmmac_poll_controller

On Tue, Sep 05, 2023 at 03:17:51PM -0700, Jakub Kicinski wrote:
> On Thu, 31 Aug 2023 14:00:04 +0200 Remi Pommarel wrote:
> > Using netconsole netpoll_poll_dev could be called from interrupt
> > context, thus using disable_irq() would cause the following kernel
> > warning with CONFIG_DEBUG_ATOMIC_SLEEP enabled:
>
> Could you rebase this on top of netdev/net? It does not apply:

Sure will do, thanks.