Re: [RFC][Patch] IBM Real-Time "SMI Free" mode driver -v5

From: Henrique de Moraes Holschuh
Date: Fri Sep 24 2010 - 22:08:10 EST


On Fri, 24 Sep 2010, Vernon Mauery wrote:
> >>+/* The RTL table as presented by the EBDA: */
> >>+struct ibm_rtl_table {
> >>+ char signature[5];
> >
> >Question: are all 5 bytes of signature[] used? It looks like the search code
> >only checks for 32 bits of signature (and the last byte can be garbage?).
>
> Technically, the 5 bytes are supposed to be "_RTL_", but it is a lot
> easier to just check _RTL since we can do that with a single read.
> I suppose I could do a 64-bit read and mask the bits that matter.

Well, as long as you guys write in stone there at IBM that you will
remember to not have a possible future _RTL2_ that would clash horribly
with an non-up-to-date version of the driver that has no clue about
RTL2 and still would match the signature because it only looks at the first
32 bits...

--
"One disk to rule them all, One disk to find them. One disk to bring
them all and in the darkness grind them. In the Land of Redmond
where the shadows lie." -- The Silicon Valley Tarot
Henrique Holschuh
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