Messages in this thread | | | Date | Mon, 14 Jan 2013 19:04:23 +0100 | From | Borislav Petkov <> | Subject | Re: [PATCH v7u1 24/31] x86, boot: Not need to check setup_header version for setup_data |
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On Mon, Jan 14, 2013 at 09:37:36AM -0800, H. Peter Anvin wrote: > No, this is a case of cargo-cult programming. I asked Yinghai to > remove it. > > It is cargo-cult programming because the value of boot_params.hdr > comes from the kernel itself, so all you're doing is telling you the > boot protocol version associated with the kernel itself, which we > already know.
LOOL. Great.
> If we find a bootloader that does that incorrectly (e.g. if kexec > were to blindly copy struct boot_params from the older kernel... > which ironically would be better than the current situation) then > the right thing to do would be to have a central place which scrub > out the fields and just force them to zero rather than putting a > bunch of tests all over the place.
Ok, I didn't realize that.
And besides, nothing stops a silly boot loader from adjusting boot_params.hdr.version so that the check - or any check for that matter - passes, AFAICT.
See, this is exactly the reason why I'm trying to explain to Yinghai why it is a Good Thing to document stuff like that at least in commit messages.
Thanks.
-- Regards/Gruss, Boris.
Sent from a fat crate under my desk. Formatting is fine. --
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