How queue lock can synchronize them if we do not hold queue lock
for entire duration and setup of request, including drive->srequest
setup?
> After all ide_raw_taskfile only gets used for REQ_SPECIAL request
> types. This does *not* contain normal data request from block IO.
> As of master slave issues - well we have the data pre allocated per
> device not per channel! If q->request_fn would properly return the
> error count instead of void, we could even get rid ot the
> checking for rq->errors after finishment... But well that's
> entierly different story.
For example do_cmd_ioctl() invokes ide_raw_taskfile, without any locking.
Two programs, both issuing HDIO_DRIVE_CMD at same time, will compete
over one drive->srequest struct: you'll get same drive->srequest structure
submitted twice to blk_insert_request (hm, Jens, will this trigger
BUG, or will this just damage request list?).
Petr Vandrovec
vandrove@vc.cvut.cz
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