kern/152768: Weird check in mfi(4)

[Sascha Wildner]

>Number:         152768
>Category:       kern
>Synopsis:       Weird check in mfi(4)
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu Dec 02 08:40:10 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Sascha Wildner
>Release:        none :)
>Organization:
>Environment:
>Description:
Hi there,

I recently ported FreeBSD's mfi(4) driver to DragonFly BSD and when running clang's static analyzer on the kernel, it found:

http://yoyodyne.ath.cx/tmp/scan-build-2010-12-01-1/report-tCmTHj.html#EndPath

If device is T_DIRECT (0x00) or T_PROCESSOR (0x03) then (device & 0xe0) can't be true. It kinda smells like the intention was something different here, though I'm not sure which, so I thought I'd report it.

Kind regards,
Sascha

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>Fix:


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