he function blk_get_request() can return NULL in some cases. There are checks on it if function is called with argumetns one of which is GFP_ATOMIC/GFP_NOIO/etc. If system couldn't find request blk_get_request() return NULL. But if there is function call with argument __GFP_WAIT the system will wait until get request or the queue becomes dead. If something kills the queue, blk_get_request() return NULL and next operations will lead to errors. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Marina Makienko <makienko@xxxxxxxxx> --- drivers/ide/ide-pm.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/drivers/ide/ide-pm.c b/drivers/ide/ide-pm.c index 9240609..4412f24 100644 --- a/drivers/ide/ide-pm.c +++ b/drivers/ide/ide-pm.c @@ -19,6 +19,10 @@ int generic_ide_suspend(struct device *dev, pm_message_t mesg) memset(&rqpm, 0, sizeof(rqpm)); rq = blk_get_request(drive->queue, READ, __GFP_WAIT); + + if (!rq) + return -EIO; + rq->cmd_type = REQ_TYPE_PM_SUSPEND; rq->special = &rqpm; rqpm.pm_step = IDE_PM_START_SUSPEND; @@ -59,6 +63,8 @@ int generic_ide_resume(struct device *dev) memset(&rqpm, 0, sizeof(rqpm)); rq = blk_get_request(drive->queue, READ, __GFP_WAIT); + if (!rq) + return -EIO; rq->cmd_type = REQ_TYPE_PM_RESUME; rq->cmd_flags |= REQ_PREEMPT; rq->special = &rqpm; -- 1.7.7 -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
