Re: [PATCH 2/4] scsi: Fix device removal NULL pointer dereference

[Bart Van Assche <bvanassche@acm.org>]

On 06/25/12 21:14, James Bottomley wrote:

> On Mon, 2012-06-25 at 18:15 +0000, Bart Van Assche wrote:
>> diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
>> index 6dfb978..c26ef49 100644
>> --- a/drivers/scsi/scsi_lib.c
>> +++ b/drivers/scsi/scsi_lib.c
>> @@ -406,10 +406,7 @@ static void scsi_run_queue(struct request_queue *q)
>>  	LIST_HEAD(starved_list);
>>  	unsigned long flags;
>>  
>> -	/* if the device is dead, sdev will be NULL, so no queue to run */
>> -	if (!sdev)
>> -		return;
>> -
>> +	BUG_ON(!sdev);
> 
> Needs to be a blk_queue_dead() check as well.


Callers of scsi_run_queue() don't hold the queue lock. Does it make
sense to test whether the queue is dead without the queue lock being held ?

>> +	BUG_ON(!sdev);
> 
> I'm with Tejun, these BUG_ON's are now pretty pointless.


OK, I'll remove these.

Bart.