Following trace pops up if we try to suspend with 3c59x ethernet NIC
brought down:
root@b1:~# ifconfig eth16 down
root@b1:~# echo mem > /sys/power/state
...
3c59x 0000:00:10.0: suspend
3c59x 0000:00:10.0: PME# disabled
Trying to free already-free IRQ 48
------------[ cut here ]------------
Badness at c00554e4 [verbose debug info unavailable]
NIP: c00554e4 LR: c00554e4 CTR: c019a098
REGS: c7975c60 TRAP: 0700 Not tainted (2.6.31-rc4)
MSR: 00021032 <ME,CE,IR,DR> CR: 28242422 XER: 20000000
TASK = c79cb0c0[1746] 'bash' THREAD: c7974000
...
NIP [c00554e4] __free_irq+0x108/0x1b0
LR [c00554e4] __free_irq+0x108/0x1b0
Call Trace:
[c7975d10] [c00554e4] __free_irq+0x108/0x1b0 (unreliable)
[c7975d30] [c005559c] free_irq+0x10/0x24
[c7975d40] [c01e21ec] vortex_suspend+0x70/0xc4
[c7975d60] [c017e584] pci_legacy_suspend+0x58/0x100
This is because the driver manages interrupts without checking for
netif_running().
Though, there are few other issues with suspend/resume in this driver.
The intention of calling free_irq() in suspend() was to avoid any
possible spurious interrupts (see commit 5b039e681b8c5f30aac9cc04385
"3c59x PM fixes"). But,
- On resume, the driver was requesting IRQ just after pci_set_master(),
but before vortex_up() (which actually resets 3c59x chips).
- Issuing free_irq() on a shared IRQ doesn't guarantee that a buggy
HW won't trigger spurious interrupts in another driver that
requested the same interrupt. So, if we want to protect from
unexpected interrupts, then on suspend we should issue disable_irq(),
not free_irq().
Signed-off-by: Anton Vorontsov <avorontsov@xxxxxxxxxxxxx>
---
drivers/net/3c59x.c | 12 +++---------
1 files changed, 3 insertions(+), 9 deletions(-)
diff --git a/drivers/net/3c59x.c b/drivers/net/3c59x.c
index c34aee9..7cdd4b0 100644
--- a/drivers/net/3c59x.c
+++ b/drivers/net/3c59x.c
@@ -807,10 +807,10 @@ static int vortex_suspend(struct pci_dev *pdev, pm_message_t state)
if (netif_running(dev)) {
netif_device_detach(dev);
vortex_down(dev, 1);
+ disable_irq(dev->irq);
}
pci_save_state(pdev);
pci_enable_wake(pdev, pci_choose_state(pdev, state), 0);
- free_irq(dev->irq, dev);
pci_disable_device(pdev);
pci_set_power_state(pdev, pci_choose_state(pdev, state));
}
@@ -833,18 +833,12 @@ static int vortex_resume(struct pci_dev *pdev)
return err;
}
pci_set_master(pdev);
- if (request_irq(dev->irq, vp->full_bus_master_rx ?
- &boomerang_interrupt : &vortex_interrupt, IRQF_SHARED, dev->name, dev)) {
- pr_warning("%s: Could not reserve IRQ %d\n", dev->name, dev->irq);
- pci_disable_device(pdev);
- return -EBUSY;
- }
if (netif_running(dev)) {
err = vortex_up(dev);
if (err)
return err;
- else
- netif_device_attach(dev);
+ enable_irq(dev->irq);
+ netif_device_attach(dev);
}
}
return 0;
--
1.6.3.3
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