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From: David Laight <David.Laight@ACULAB.COM>
To: "'Arnd Bergmann'" <arnd@arndb.de>
CC: Boris Ostrovsky <boris.ostrovsky@oracle.com>,
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Subject: RE: [PATCH] xen: hypercall: fix out-of-bounds memcpy
Thread-Topic: [PATCH] xen: hypercall: fix out-of-bounds memcpy
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Date: Mon, 5 Feb 2018 13:58:55 +0000
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From: Arnd Bergmann
> Sent: 05 February 2018 12:37
....
> > Are the EVTCHNOP_xxx values dense?
> > In which case an array is almost certainly better than the switch statement.
> 
> They are, yes. PHYSDEVOP_xxx are also consecutive by start at '4'.
> Dan made the same comment earlier, and I replied that my I had
> considered it but went for the more failsafe route. I also verified my
> assumption now that gcc in fact is smart enough to turn this
> into a table by itself:

I've never spotted that optimisation, must be fairly new.

	David