On Thu, Sep 10, 2009 at 09:30:03AM -0600, Jonathan Corbet wrote: > On Thu, 10 Sep 2009 18:37:34 +0000 > iceberg <strakh@xxxxxxxxx> wrote: > > > In ./drivers/media/video/cafe_ccic.c, in function cafe_pci_probe: > > Mutex must be unlocked before exit > > 1. On paths starting with mutex lock in line 1912, then continuing in lines: > > 1929, 1936 (goto unreg) and 1940 (goto iounmap) . > > 2. On path starting in line 1971 mutex lock, and then continuing in line 1978 > > (goto out_smbus) mutex. > > That's a definite bug, but I hate all those unlocks in the error > branches. As it happens, we don't really need the mutex until the > device has been exposed to the rest of the kernel, so I propose the > following as a better patch. > > Thanks for pointing this out, If we can first pair of mutex_lock and mutex_unlock: Fix lock imbalances in function device_authorization. Signed-off-by: Alexander Strakh <strakh@xxxxxxxxx> --- diff --git a/./drivers/media/video/cafe_ccic.c b/../b/drivers/media/video/cafe_ccic.c index c4d181d..4c6bc86 100644 --- a/./drivers/media/video/cafe_ccic.c +++ b/../b/drivers/media/video/cafe_ccic.c @@ -1909,7 +1909,6 @@ static int cafe_pci_probe(struct pci_dev *pdev, goto out_free; mutex_init(&cam->s_mutex); - mutex_lock(&cam->s_mutex); spin_lock_init(&cam->dev_lock); cam->state = S_NOTREADY; cafe_set_config_needed(cam, 1); @@ -1949,7 +1948,6 @@ static int cafe_pci_probe(struct pci_dev *pdev, * because the sensor could attach in this call chain, leading to * unsightly deadlocks. */ - mutex_unlock(&cam->s_mutex); /* attach can deadlock */ ret = cafe_smbus_setup(cam); if (ret) goto out_freeirq; @@ -1975,7 +1973,7 @@ static int cafe_pci_probe(struct pci_dev *pdev, cam->vdev.v4l2_dev = &cam->v4l2_dev; ret = video_register_device(&cam->vdev, VFL_TYPE_GRABBER, -1); if (ret) - goto out_smbus; + goto out_unlock; video_set_drvdata(&cam->vdev, cam); /* @@ -1990,6 +1988,8 @@ static int cafe_pci_probe(struct pci_dev *pdev, mutex_unlock(&cam->s_mutex); return 0; +out_unlock: + mutex_unlock(&cam->s_mutex); out_smbus: cafe_smbus_shutdown(cam); out_freeirq: -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
