On Fri, Feb 18 2005, Philip R Auld wrote: > Hi, > > Rumor has it that on Fri, Feb 18, 2005 at 02:59:32PM +0100 Jens Axboe said: > > On Fri, Feb 18 2005, Philip R Auld wrote: > > ... > > > Or make all users of submit_bio take and release and extra reference > > > like submit_bh. > > > > The queue lock is still held at that point, so the driver hasn't had a > > chance to process the request yet. > > Interesting. This is not a theoretical problem though. I've got traces of > the oops showing the bio getting freed before the bio_sync(bio) test. > When you say driver here what level do you mean? scsi_request_fn at > least drops the queue lock.
But it must be holding the lock to retrieve the request in question, so there should be no opening for a completion race there. > What if it's merged instead of added directly? That could also get to > the same place. Same deal - if the request is already seen by the driver, merging is not allowed. If not, then the same rules apply. > The end_io callback _is_ getting called before __make_request > does its "if(bio_sync(bio))" test. Sounds strange, it sounds like a driver issue. If you have time, please do poke some more at this. I'll try to be responsive, but I'm busy with other things atm. Are you using a vanilla kernel? -- Jens Axboe - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
