[LinuxBIOS] linuxbios selling points - Was: Fallback checking / SMM disadvantages

WarrenHead warrenhead at gmail.com
Thu Mar 29 15:45:44 CEST 2007

Quux schreef:
> 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

Thanks for your answers.
I for one see the avoidance of bios code that interrupts the careful 
planning of realtime os'ses as something rather straightforward; in the 
way of a sellable benefit. I bet this could really be swept up as a 
selling point, barring you get audio folks to state they see/notice a 
Are people onto this? Creating a measurable before/after situation?

The security item is interesting, but not as much. Even if 'evil' bios 
manufacturers were daily snooping around on my machine, I can't see it, 
so how would I feel better without it? I haven't experienced anything 
bad, so I can't compare. This feels a bit like reading my horoscope to 
see whether I should even bother to get up, or taking precautionary 
extra vitamins because the label says I need them. Too much fear.
Besides, I can see people saying that this is a feature they want. They 
want some big brother to care about their machine. It makes them feel 
cared for. It's just the secrecy that is bad.

But still, what about the boot time savings? How substantial is this?
Now that hibernation is 'here', this point feels moot. Is it?

Cheers, Warren

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