From: Sebastian Ott Date: Mon, 22 Jun 2009 10:08:21 +0000 (+0200) Subject: [S390] dasd: fix refcounting in dasd_change_state X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=181d95229b0931ee2ce6aad7348079cbc10e8d05;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git [S390] dasd: fix refcounting in dasd_change_state To set a dasd online dasd_change_state is called twice. The first cycle will schedule initial analysis of the device, set the rc to -EAGAIN and will not touch the device state any more. The initial analysis will in turn call dasd_change_state to increase the state to the final DASD_STATE_ONLINE. If the dasd_change_state on the second thread outruns the other one both finish with the state set to DASD_STATE_ONLINE and the device refcount will be decreased by 2. Fix this by leaving dasd_change_state on rc == -EAGAIN so that the refcount will always be decreased by 1. Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky --- diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 99e71536213a..749836668655 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -470,7 +470,7 @@ static int dasd_decrease_state(struct dasd_device *device) */ static void dasd_change_state(struct dasd_device *device) { - int rc; + int rc; if (device->state == device->target) /* Already where we want to go today... */ @@ -479,8 +479,10 @@ static void dasd_change_state(struct dasd_device *device) rc = dasd_increase_state(device); else rc = dasd_decrease_state(device); - if (rc && rc != -EAGAIN) - device->target = device->state; + if (rc == -EAGAIN) + return; + if (rc) + device->target = device->state; if (device->state == device->target) { wake_up(&dasd_init_waitq);