[PATCH 5.10 025/131] net:sfc: fix non-freed irq in legacy irq mode

From: Greg Kroah-Hartman
Date: Mon Jun 14 2021 - 07:09:38 EST


From: Íñigo Huguet <ihuguet@xxxxxxxxxx>

[ Upstream commit 8f03eeb6e0a0a0b8d617ee0a4bce729e47130036 ]

SFC driver can be configured via modparam to work using MSI-X, MSI or
legacy IRQ interrupts. In the last one, the interrupt was not properly
released on module remove.

It was not freed because the flag irqs_hooked was not set during
initialization in the case of using legacy IRQ.

Example of (trimmed) trace during module remove without this fix:

remove_proc_entry: removing non-empty directory 'irq/125', leaking at least '0000:3b:00.1'
WARNING: CPU: 39 PID: 3658 at fs/proc/generic.c:715 remove_proc_entry+0x15c/0x170
...trimmed...
Call Trace:
unregister_irq_proc+0xe3/0x100
free_desc+0x29/0x70
irq_free_descs+0x47/0x70
mp_unmap_irq+0x58/0x60
acpi_unregister_gsi_ioapic+0x2a/0x40
acpi_pci_irq_disable+0x78/0xb0
pci_disable_device+0xd1/0x100
efx_pci_remove+0xa1/0x1e0 [sfc]
pci_device_remove+0x38/0xa0
__device_release_driver+0x177/0x230
driver_detach+0xcb/0x110
bus_remove_driver+0x58/0xd0
pci_unregister_driver+0x2a/0xb0
efx_exit_module+0x24/0xf40 [sfc]
__do_sys_delete_module.constprop.0+0x171/0x280
? exit_to_user_mode_prepare+0x83/0x1d0
do_syscall_64+0x3d/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f9f9385800b
...trimmed...

Signed-off-by: Íñigo Huguet <ihuguet@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/sfc/nic.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/sfc/nic.c b/drivers/net/ethernet/sfc/nic.c
index d1e908846f5d..22fbb0ae77fb 100644
--- a/drivers/net/ethernet/sfc/nic.c
+++ b/drivers/net/ethernet/sfc/nic.c
@@ -90,6 +90,7 @@ int efx_nic_init_interrupt(struct efx_nic *efx)
efx->pci_dev->irq);
goto fail1;
}
+ efx->irqs_hooked = true;
return 0;
}

--
2.30.2