s390/3270: fix crash with multiple reset device requests

If the 3270 device is detached the initial reset device request will
stays pending until the device is operational. A second reset device
call will reuse the same request structure which will cause an oops.
Add a check to see if the reset device request is already pending
and do nothing in this case.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Martin Schwidefsky 2014-03-21 15:24:27 +01:00
parent 0ccc8b7ac8
commit bd1cb5de14

View file

@ -632,6 +632,8 @@ raw3270_reset_device_cb(struct raw3270_request *rq, void *data)
raw3270_size_device_done(rp);
} else
raw3270_writesf_readpart(rp);
memset(&rp->init_reset, 0, sizeof(rp->init_reset));
memset(&rp->init_data, 0, sizeof(rp->init_data));
}
static int
@ -639,9 +641,10 @@ __raw3270_reset_device(struct raw3270 *rp)
{
int rc;
/* Check if reset is already pending */
if (rp->init_reset.view)
return -EBUSY;
/* Store reset data stream to init_data/init_reset */
memset(&rp->init_reset, 0, sizeof(rp->init_reset));
memset(&rp->init_data, 0, sizeof(rp->init_data));
rp->init_data[0] = TW_KR;
rp->init_reset.ccw.cmd_code = TC_EWRITEA;
rp->init_reset.ccw.flags = CCW_FLAG_SLI;
@ -850,7 +853,7 @@ raw3270_create_device(struct ccw_device *cdev)
char *ascebc;
int rc;
rp = kmalloc(sizeof(struct raw3270), GFP_KERNEL | GFP_DMA);
rp = kzalloc(sizeof(struct raw3270), GFP_KERNEL | GFP_DMA);
if (!rp)
return ERR_PTR(-ENOMEM);
ascebc = kmalloc(256, GFP_KERNEL);