xgbe_powerdown() takes an irqsave spinlock, then calls flush_workqueue()
which takes a mutex. DEBUG_ATOMIC_SLEEP isn't happy about this:
| BUG: sleeping function called from invalid context at [...] mutex.c:281
| in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 2733, name: bash
| CPU: 4 PID: 2733 Comm: bash Tainted: G W 5.4.0-rc3 #113
| Hardware name: AMD Seattle (Rev.B0) Development Board (Overdrive) (DT)
| Call trace:
| show_stack+0x24/0x30
| dump_stack+0xb0/0xf8
| ___might_sleep+0x124/0x148
| __might_sleep+0x54/0x90
| mutex_lock+0x2c/0x80
| flush_workqueue+0x84/0x420
| xgbe_powerdown+0x6c/0x108
| xgbe_platform_suspend+0x34/0x80
| pm_generic_freeze+0x3c/0x58
| acpi_subsys_freeze+0x2c/0x38
| dpm_run_callback+0x3c/0x1e8
| __device_suspend+0x130/0x468
| dpm_suspend+0x114/0x388
| hibernation_snapshot+0xe8/0x378
| hibernate+0x18c/0x2f8
Drop the lock for the duration of xgbe_powerdown(). We have already
stopeed the timers, so service_work can't be re-queued. Move the
pdata->power_down flag earlier so that it can be used by the interrupt
handler to know not to re-queue the tx_tstamp_work.
Signed-off-by: James Morse <james.mo...@arm.com>
---
RFC as I'm not familiar with this driver. I'm happy to test a better fix!
---
drivers/net/ethernet/amd/xgbe/xgbe-drv.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
index 98f8f2033154..bfba7effcf9f 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
@@ -480,6 +480,8 @@ static void xgbe_isr_task(unsigned long data)
struct xgbe_channel *channel;
unsigned int dma_isr, dma_ch_isr;
unsigned int mac_isr, mac_tssr, mac_mdioisr;
+ unsigned long flags;
+ bool power_down;
unsigned int i;
/* The DMA interrupt status register also reports MAC and MTL
@@ -558,8 +560,14 @@ static void xgbe_isr_task(unsigned long data)
/* Read Tx Timestamp to clear interrupt */
pdata->tx_tstamp =
hw_if->get_tx_tstamp(pdata);
- queue_work(pdata->dev_workqueue,
- &pdata->tx_tstamp_work);
+
+ spin_lock_irqsave(&pdata->lock, flags);
+ power_down = pdata->power_down;
+ spin_unlock_irqrestore(&pdata->lock, flags);
+
+ if (!power_down)
+ queue_work(pdata->dev_workqueue,
+ &pdata->tx_tstamp_work);
}
}
@@ -1256,16 +1264,22 @@ int xgbe_powerdown(struct net_device *netdev, unsigned
int caller)
netif_tx_stop_all_queues(netdev);
+ /* Stop service_work being re-queued by the service_timer */
xgbe_stop_timers(pdata);
+
+ /* Stop tx_tstamp_work being re-queued after flush_workqueue() */
+ pdata->power_down = 1;
+
+ /* drop the lock to allow flush_workqueue() to sleep. */
+ spin_unlock_irqrestore(&pdata->lock, flags);
flush_workqueue(pdata->dev_workqueue);
+ spin_lock_irqsave(&pdata->lock, flags);
hw_if->powerdown_tx(pdata);
hw_if->powerdown_rx(pdata);
xgbe_napi_disable(pdata, 0);
- pdata->power_down = 1;
-
spin_unlock_irqrestore(&pdata->lock, flags);
DBGPR("<--xgbe_powerdown\n");
--
2.20.1
