[PATCH net-next v2] declance: Remove IRQF_ONESHOT

Sebastian Andrzej Siewior
2026-01-27T13:53:38Z

Passing IRQF_ONESHOT ensures that the interrupt source is masked until
the secondary (threaded) handler is done. If only a primary handler is
used then the flag makes no sense because the interrupt can not fire
(again) while its handler is running.
The flag also disallows force-threading of the primary handler and the
irq-core will warn about this as of commit aef30c8d569c0 ("genirq: Warn
about using IRQF_ONESHOT without a threaded handler").

The IRQF_ONESHOT flag was added in commit 0fabe1021f8bc ("MIPS:
DECstation I/O ASIC DMA interrupt classes"). It moved
clear_ioasic_dma_irq() from the driver into the irq-chip.
For EOI interrupts the clear_ioasic_dma_irq() callback is now invoked as
->irq_eoi() which is invoked after the IRQ was handled while the
interrupt is masked due to IRQF_ONESHOT. Without IRQF_ONESHOT it would
be invoked while interrupt is unmasked (but interrupts are disabled).

If it is *required* to invoke EOI-ack while the interrupt is masked (and
not a misunderstanding) due to irq-chip cascading/ hierarchical reasons
then using handle_fasteoi_mask_irq() as flow-handler would be the right
way to do so.

Remove IRQF_ONESHOT to irqflags.

Cc: Andrew Lunn <andrew+netdev@lunn.ch>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---

The mentioned genirq commit is in -next.

drivers/net/ethernet/amd/declance.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/amd/declance.c b/drivers/net/ethernet/amd/declance.c
index 8d05a0c5f2d5d..e6d56fcdc1ddd 100644
--- a/drivers/net/ethernet/amd/declance.c
+++ b/drivers/net/ethernet/amd/declance.c
@@ -813,7 +813,7 @@ static int lance_open(struct net_device *dev)
if (lp->dma_irq >= 0) {
unsigned long flags;

- if (request_irq(lp->dma_irq, lance_dma_merr_int, IRQF_ONESHOT,
+ if (request_irq(lp->dma_irq, lance_dma_merr_int, 0,
"lance error", dev)) {
free_irq(dev->irq, dev);
printk("%s: Can't get DMA IRQ %d\n", dev->name,
--
2.51.0