From: Julia Lawall <Julia.Lawall@xxxxxxx> Converting kzalloc to devm_kzalloc simplifies the code and ensures that the result, alert, is freed after the irq allocated by the subsequent devm_request_irq. This in turn ensures that when an interrupt can be triggered, the alert structure is still available. The problem of a free after a devm_request_irq was found using the following semantic match (http://coccinelle.lip6.fr/) // <smpl> @r exists@ expression e1,e2,x,a,b,c,d; identifier free; position p1,p2; @@ devm_request_irq@p1(e1,e2,...,x) ... when any when != e2 = a when != x = b if (...) { ... when != e2 = c when != x = d free@p2(...,x,...); ... return ...; } // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxx> --- drivers/i2c/i2c-smbus.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/i2c-smbus.c b/drivers/i2c/i2c-smbus.c index df3e0bf..50a36cf 100644 --- a/drivers/i2c/i2c-smbus.c +++ b/drivers/i2c/i2c-smbus.c @@ -142,7 +142,8 @@ static int smbalert_probe(struct i2c_client *ara, struct i2c_adapter *adapter = ara->adapter; int res; - alert = kzalloc(sizeof(struct i2c_smbus_alert), GFP_KERNEL); + alert = devm_kzalloc(&ara->dev, sizeof(struct i2c_smbus_alert), + GFP_KERNEL); if (!alert) return -ENOMEM; @@ -154,10 +155,8 @@ static int smbalert_probe(struct i2c_client *ara, if (setup->irq > 0) { res = devm_request_irq(&ara->dev, setup->irq, smbalert_irq, 0, "smbus_alert", alert); - if (res) { - kfree(alert); + if (res) return res; - } } i2c_set_clientdata(ara, alert); @@ -167,14 +166,12 @@ static int smbalert_probe(struct i2c_client *ara, return 0; } -/* IRQ resource is managed so it is freed automatically */ +/* IRQ resource and alert are managed so they are freed automatically */ static int smbalert_remove(struct i2c_client *ara) { struct i2c_smbus_alert *alert = i2c_get_clientdata(ara); cancel_work_sync(&alert->alert); - - kfree(alert); return 0; } -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
