On Fri, 2005-11-11 at 13:38 -0600, Cameron, Steve wrote: > About the locking first, > > So, there's one part that I was a little worried about, where > it does this in a couple places: > > c = (ctlr_info_t **) &scsicmd->device->host->hostdata[0]; > > (gets our adapter structure by following pointers in the scsi > command) > > So, if that pointer chain can change suddenly, then my code is bad. > > Can doing "echo scsi remove-single-device . . . > /proc/scsi/scsi" > cause that pointer chain to break? I noticed I can yank a disk > out from under a mounted filesystem with > "echo scsi remove-single-device" It wasn't obvious to me whether > doing that would affect that pointer chain though, though I could > imagine it might. > > Or am I barking up the wrong tree worrying about > the scsicmd->device->host->hostdata pointer chain > getting yanked out from under me? No, the pointers are all held in place. Even if everyone else releases their references, the commmand still contains a reference to the device (which holds it from being released) and the device likewise contains a reference to the host. James - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
