From: Julian Ruess julianr@linux.ibm.com
commit 78d0f94902afce8ec2c7a60f600cc0e3729d7412 upstream.
This patch prevents the system from crashing when unloading the ISM module.
How to reproduce: Attach an ISM device and execute 'rmmod ism'.
Error-Log: - Trying to free already-free IRQ 0 - WARNING: CPU: 1 PID: 966 at kernel/irq/manage.c:1890 free_irq+0x140/0x540
After calling ism_dev_exit() for each ISM device in the exit routine, pci_unregister_driver() will execute ism_remove() for each ISM device. Because ism_remove() also calls ism_dev_exit(), free_irq(pci_irq_vector(pdev, 0), ism) is called twice for each ISM device. This results in a crash with the error 'Trying to free already-free IRQ'.
In the exit routine, it is enough to call pci_unregister_driver() because it ensures that ism_dev_exit() is called once per ISM device.
Cc: stable@vger.kernel.org # 6.3+ Fixes: 89e7d2ba61b7 ("net/ism: Add new API for client registration") Reviewed-by: Niklas Schnelle schnelle@linux.ibm.com Signed-off-by: Julian Ruess julianr@linux.ibm.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/s390/net/ism_drv.c | 8 -------- 1 file changed, 8 deletions(-)
--- a/drivers/s390/net/ism_drv.c +++ b/drivers/s390/net/ism_drv.c @@ -774,14 +774,6 @@ static int __init ism_init(void)
static void __exit ism_exit(void) { - struct ism_dev *ism; - - mutex_lock(&ism_dev_list.mutex); - list_for_each_entry(ism, &ism_dev_list.list, list) { - ism_dev_exit(ism); - } - mutex_unlock(&ism_dev_list.mutex); - pci_unregister_driver(&ism_driver); debug_unregister(ism_debug_info); }