[LinuxBIOS] Fallback checking / SMM disadvantages

Quux pawn2be.wild at yahoo.de
Thu Mar 29 10:18:04 CEST 2007

SMM is killing hard "real time capability" and also killing hard 
security, unless it's code is public.
Those TCP/IP stacks within SMM-BIOS do not make everyone happy.   --Q

Carl-Daniel Hailfinger schrieb:
> On 27.03.2007 16:41, WarrenHead wrote:
>> So, as an ordinary person who just owns a pc, what would I get out of 
>> using linuxbios instead of the proprietary one that came with my machine 
>> already?
> There's one instant benefit: Better realtime behaviour for Professional
> Audio/Video applications. Let me explain: All recent proprietary BIOS
> releases use SMM (maybe not all, but I haven't seen one without).
> SMM routines are not under the control of the operating system and will
> be executed at arbitrary points in time with unknown (although mostly
> noticeable) duration and the operating system will FREEZE during that
> time. If you depend on low latency for audio applications, even "hard
> realtime" kernels will never be able to guarantee you any latency,
> simply because they don't know when the BIOS decides to block the CPU
> with SMM.
> Regards,
> Carl-Daniel

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