Messages in this thread |  | | | Date | Thu, 02 Apr 2009 00:15:20 -0400 (EDT) | | From | Len Brown <> | | Subject | Re: [GIT PULL] x86 setup BIOS workarounds |
| |
> + /* ACPI 3.0 added the extended flags support. If bit 0 > + in the extended flags is zero, we're supposed to simply > + ignore the entry -- a backwards incompatible change! */ > + if (size > 20 && !(buf.ext_flags & 1)) > + continue;
At the risk of rushing to the defense of the ACPI spec...
This does not look like a backwards incompatible change to me.
In ACPI 2.0, size of 20 is always returned, and it would be a Linux bug if we examined the undefined values after byte 19.
In ACPI 3.0, byte 20 is now defined. So if the BIOS returns a size >= 21, we are permitted to examine byte 20.
So I agree with the test above, but I do not agree with the comment.
thanks, Len Brown, Intel Open Source Technology Center
|  |