s390/ism: Fix trying to free already-freed IRQ by repeated ism_dev_exit()

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>

diff --git a/drivers/s390/net/ism_drv.c b/drivers/s390/net/ism_drv.c
index 8acb9eb..c2096e4 100644 (file)
--- a/drivers/s390/net/ism_drv.c
+++ b/drivers/s390/net/ism_drv.c
@@ -771,14 +771,6 @@ 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);
 }