Luben Tuikov wrote:
David, when I said ``... the transport will tell the LLDD that the device ...'' this is *exactly* what I meant. You're just repeating it here in a more broken-down way.
OK
By transport I mean USB, FC, SPI, etc; LLDD is the transport portal and the initiator (aka the initiator port). This terminology is not really that new, but still not that old, and described in SAM-3.
I was hoping for something described in the 2.5.58 kernel docs, which only talks about LLD (Documentation/scsi) except in one case (looked like a typo) ... I remember SAM-3 as a kind of missile!
We just cannot let a transport event just wipe out a device, without consulting hotplugging first -- think security.
Certainly "device gone" would be an auditable event, but this is primarily an integrity issue: don't free objects until other components have stopped using them. If any components attach security policies to that "gone" state transition, that'd be atypical but purely their own business. (Like a transport erasing session master keys ... most transports wouldn't have them, and would likely erase them as soon as the device is known to be gone, no hotplug involved.)
That is, when a transport event takes place, the LLDD doesn't have to ``run to'' SCSI Core right away. Just let the kernel know about this event, and start returning errors, on newly queued commands. The kernel will decide what to do about this device going away, i.e. hotplugging, sysop notification, etc.
Sounds right. Except that it'd normally be the SCSI core that we "let" know about the event. (Not always, I can imagine that some transports might be able to kick in recovery procedures and find some other path for accessing the device. But in such cases, SCSI might never see the device as "gone" ... ) - Dave ------------------------------------------------------- This SF.NET email is sponsored by: FREE SSL Guide from Thawte are you planning your Web Server Security? Click here to get a FREE Thawte SSL guide and find the answers to all your SSL security issues. http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0026en _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
