MESSAGE
| DATE | 2014-11-14 |
| FROM | Ruben Safir
|
| SUBJECT | Subject: [NYLXS - HANGOUT] how is this research...UEFI
|
----- Forwarded message from Ruben Safir -----
Date: Fri, 14 Nov 2014 00:42:00 -0500
From: Ruben Safir
To: Samir Iabbassen
Subject: how is this research...
User-Agent: Mutt/1.5.21 (2010-09-15)
from irc tonight
I don't get it. They say the MBR is limited to 32 bits but
what does that have to do with an instruction set that says - fetch this
boot image and send it to the CPU
I know right
$100 overpriced
The thing I like about it is the very nicely done side window
that window sure must have been expensive
even if the bios can't map over 2 terabits, this shold only
be a problem if the init image is located over the addressing space
mrbrklyn, what's your question exactly?
Sachiru, fractal arc midi r2
Sachiru i think the older CM cosmos case had that as an option
Why can't the bios boot from a disk larger that 2 terabytes
it doesn't need to see the entire disk to boot, just the MBR
is very nice, has a side window version for around $80-100
Uh.
i cant say enough good about the arc midi r2
Are you familiar with the bios boot process, mrbrklyn?
I'm studying UEFI and they aways say that it can't address
over 2 gigs and I'm always scratching me head
Yes Sachiru
mostly
* EmLeX (~emx-at-unaffiliated/emlex) has joined ##hardware
it btw - I mean the old bios
damn you can get android 3.5" phones off contract for $10
s/2 gigs/2 tb
man im about to order this stuff
I don' see why not can have a sweet htpc for $166
i doubt the price on that will go down much closer to the
holidays
whats your list?
I told you :-P
mrbrklyn, research the bios parameter block.
MSI h81i mini itx mobo -- CM elite 130 case -- G3220 processor
i have psu ram ssd
* gringo has quit (Ping timeout: 240 seconds)
and a home nas for storage
yeah i dont see it going much lower
yeah
the cm 130 looks amazing since it is only $45
* ldiamond (~ldiamond-at-MTRLPQ4362W-LP140-01-2925069565.dsl.bell.ca) has
* joined ##hardware
Sachiru - that is what is confusing me!
all interpretation of data structures like MBR partition
tables and so-called BIOS Parameter Blocks is done by the boot program
in the boot sector itself or by other programs loaded through the boot
process and is beyond the scope of BIOS
every time I order anything tho I figure out later what I shuld
have ordered instead
you know what I mean eHAPPY ?
yup
i dont see how I can go wrong with those 3 pieces though
atleast its not retail prices
so as long as the boot secture isn't strangly configures
after two terabytes, then why does it matter? The OS is going to start
and leverage the complete CPU and I/O modules
eHAPPY, what do you mean
-at-mrbrklyn: Tell me how large the boot program in the boot
sector can be at maximum
32 bits
Hint: The boot program cannot go beyond a certain number of
bytes
And no, that's not the answer
Oh
32 bits is the memory space of the program
Basically, when the boot program is installed on a device, up
to how large can it be?
* ryaxnb (~ryaxnb-at-c-73-170-78-20.hsd1.ca.comcast.net) has joined
* ##hardware
Sachiru, 512
DF3D2 atleast when you order online you arent getting the worst
deal to start with
instead of in store
eHAPPY, I love amazon 2 day shipping :-P and I dont even have
any computer stores near me
512 bytes in the boot sector, yes, but that's not the size of
the boot program
* Compgeke|T410 (~Compgeke-at-71-82-21-252.static.leds.al.charter.com) has
* joined ##hardware
Remember that the partition table and the boot signatures
occupy space in the bootsector
http://www.newegg.com/Product/Product.aspx?Item=N82E16811139034
Ah crap, wrong link
man ubisoft is garbage
http://en.wikipedia.org/wiki/Booting#Modern_boot_loaders
Here we go
lols
ubisoft is utter faaail
I don't know
i don't either
I don't really need to know though
* Lyc has quit (Ping timeout: 265 seconds)
mrbrklyn, Consider this: MBR is typically given a bootstrap
code area of around 432 bytes. All of which need to contain the LBA
addresses of the second stage chainloader.
Which may be located ANYWHERE in a disk
Oh I was going to say one sector which is 512 but according
to what I'm reading that memory can be used to redirect
The second stage loader of boot does not necessarily reside in
the head of the drive. It can live in an area beyond the 2TB LBA mark
* day- (~day-at-unaffiliated/day) has joined ##hardware
OK - good good!
If it does live in that area, what then happens if your
bootloader tries to point to an address that is beyond 32 bits in length
it craps out
(It crashes)
Hence the need for GPT, an entirely new way of addressing it.
what is the second stage chaiun loader
Remember that the bootloader is not a single program stored in
a single chunk of space on the drive (that way lies failure due to bad
sectors, and inability to trim/remap SSDs)
BTW - that is exactly what i was thinking
It's chopped up in different parts and stored in different
locations.
If you change to GPT the constraint of 2 terabytes for the
partition should end
The second stage chainloader is dependent on the operating
system you want, the primary bios boot loader's job is to allow the user
to select which chainloaded OS's boot code to run
* day has quit (Ping timeout: 265 seconds)
* Eques (~Eques-at-c-50-161-151-165.hsd1.ca.comcast.net) has joined
* ##hardware
so then the seconday boot loader is GRUB or vmlinuz
* jwpierce3 (~jwpierce3-at-172.56.34.124) has joined ##hardware
Yes
wow there is so much stuff in the boot partition of Linux now
I haven't looked at it in a decade
And as we know, grub does not necessarily stay in the <2TB
section of the drive
which one grub or vmlinuz?
Grub
Ah wait
My bad
Not grub
Grub is at a higher layer
really... wow
* Toph (~peace-at-h69-31-230-220.dynamic.platinum.ca) has joined ##hardware
initrd ?
ooo
grub points to initrd
i can get the h81i on ebay for $50
No, initrd is higher than grub
* Toph has quit (Client Quit)
that's a bit of a savings
I'm talking about the glue code that points to grub
nothing I know of before grub
nooo it was sold today
noooo
lilo used to be installed onto the MBR itself
I never mastered grub. It just annoyed me with its
complexity
* Sachiru points to the stack of punch cards in the corner
You might be more comfortable with those then.
:)
At 51 I decided to finally go for my masters in Comp Sci
grub is easy
* majorneil (47cbc12d-at-gateway/web/freenode/ip.71.203.193.45) has joined
* ##hardware
that is why I'm dusting all this off
Uhhh... Okay?
mrbrklyn: what school do you go to
LIU
brooklyn campus or the one in, uh muttontown
* maestrojed has quit (Quit: Computer has gone to sleep.)
* arescorpio (~arescorpi-at-201-56-245-190.fibertel.com.ar) has joined
* ##hardware
* Name141 (~KFC-at-unaffiliated/bigmoopies) has joined ##hardware
* viscera has quit (Quit: viscera)
http://www.liu.edu/Brooklyn/Academics/Schools/School-of-Business-Public-Administration-and-Information-Sciences/Dept/CS/Graduate-Programs/MS-CompSci
In Brooklyn
I'm getting Stallman to come talk
lol
haha
stallman is a weirdo
He is a weirdo indeed but I love him
* Star2014 has quit (Quit: $rimburn)
So if you change to GPT, the two terabyte constraint should
end but it doesn't for booting purposes
mrbrklyn, Consider one thing as well
guy selling a gigabyte z87-ud3h + an i3 4130 for $175
thats a tempting deal tbh
Most modern motherboards come with UEFI by default, and use
legacy glue code to emulate bios boot.
* Compgeke|T410 offers $17.50
im about to offer him $150
and that is because the secondary stage chain loader can be
scattered in the partition
UEFI also does not launch any boot code in the MBR
I'm considering getting a Thinkpad T420 and throwing in
an i7 2670QM rather than bothering with a desktop
* Majorneil_ (47cbc12d-at-gateway/web/freenode/ip.71.203.193.45) has joined
* ##hardware
just keep the QX6700 there for the occasional game but
the T420 for everything else
so thats only like $60 for the board
Thus if a UEFI system sees a "legacy" BIOS boot MBR, it will
not load the MBR boot code but it will load the MBR partition table and
attempt to infer from that where to boot
for a z87 board, and a nice one too
That's if you have a decent motherboard manufacturer
Sachiru I started this jouney because I was have huge
problems installing various linux distors on my new laptop for school,
and I finally tossed the uehi back into compapability mode and
everyhting installed. I vowed to usnderstand this thing and the signed
images once and for all
actually it has pretty shitty newegg reviews....
The standard procedure for UEFI boot is that they do not load
MBR. At all. Whatsoever.
The reason for that is Secure Boot
That particular issue does not have anything to do whatsoever
with MBR/GPT
Secure Boot and Microsoft's scumbag attitude
so an assignment came up and I decided to knock off two birds
with one stone and do it in UEFI and UEFI is not well documented at all,
not like a bois is
What?
LOL
bios
UEFI is pretty much well documented
not what I've been looking at
* DF3D2 doesnt like uefi
http://www.uefi.org/specs/download
no it's not. the implementations all suck for obvious reasons.
they are new
https://www.happyassassin.net/2014/01/25/uefi-boot-how-does-that-actually-work-then/
I have 278 pages of documentation which amounts to killing
one with kindness
* ryaxnb has quit (Quit: Leaving)
but then there has been this nagging question I've had about
the 2 terab wall and it having to do with the bois addressing spacve an
I keep thing A) the Bios is passive and only needs to fecth the boot
program
* Majorneil_ has quit (Ping timeout: 246 seconds)
* majorneil has quit (Ping timeout: 246 seconds)
and who would stick the boot program at the end of a 5
terabyte drive??
* Eques has quit ()
* Haswell (~Haswell-at-unaffiliated/haswell) has joined ##hardware
mrbrklyn, What if you need to remap?
Because the first five sectors of your disk are broken?
Under BIOS you are screwed
Under UEFI, sure, why not
But yes, the main point of UEFI/GPT is addressing a drive
beyond 2TB
why is 2tb a magic number
Boot code is an unfortunate casualty of the design decisions
that they made to make sure that it "works, kind of"
if they are broken then the disk is broken, no point then
wols_ sectors die all the time
DF3D2: cause you only have a 32bit number for sectors in MBR and
each sector is 512bytes in size. tat amounts to 2TB
* Compgeke|T410 has quit (Ping timeout: 245 seconds)
that is why you have parity bits all over the file system
mrbrklyn: of course they do, and they get remapped. and if that
remappng is not possible, then your disk is dead due to dataloss
wols_, thx
-at-DF3D2= 4294967296 maximum LBA addresses x 512 Bytes per
logical block = 2 TB of addressible space
using a disk that has no more spare sectors is simply a bad idea
mrbrklyn, Remember that boot code needs to reside in ~400
bytes only
Where would you stick parity code in that?
mrbrklyn: it's actually not a bios problem, bios doesn't read
the mbr
mrbrklyn: it only runs code there
Sachiru: every disk has lots of parity information on the disk
itself that you never will and can see
* Deihmos (~Deihmos-at-unaffiliated/deihmos) has joined ##hardware
-at-wols: Yes, and that is out of bios/MBR's problem
And not even related to mbr limitations
mrbrklyn: if you aren't using windows, there's actually nothing
preventing you from booting from a >2tb drive on a reasonably modern
bios system
* maestrojed (~maestroje-at-c-98-246-149-230.hsd1.or.comcast.net) has
* joined ##hardware
so regardless then how would the bios and bootloaded in 412 k
of mem handle this problem anyway
Not 412k
412 bytes.
Not even half a kilobyte
right!
mrbrklyn: normally the code in 512b just loads a larger section
of code from a fixed address or via a simple pointer chain
some have basic filesystem support
at least to find where filesystem are
* maestrojed has quit (Max SendQ exceeded)
* Shaun413 has quit (Ping timeout: 256 seconds)
lol this movie about muhammad ali is great
or is it mohammed ?
* maestrojed (~maestroje-at-c-98-246-149-230.hsd1.or.comcast.net) has
* joined ##hardware
mrbrklyn: have you lived in NY for a while?
so even still, wherever the secondary chain loader way ....
out younder past 2 terabytes
i'm from lawn guyland in case you didn't notice :P
little bit ;)
* Foxhoundz (~Foxhoundz-at-unaffiliated/foxhoundz) has joined ##hardware
http://www.mrbrklyn.com/
mrbrklyn: to encourage uefi adoption, microsoft doesn't have
any method to boot from gpt on a bios system, or from mbr on a uefi
system
that's why you hear it mentioned
oh that is INTRESTING because I was reading one article where
he was busting his tuchas to get a 5 terabyte raid to work as a boot
device and it seemed that the bios was failing
1
http://www.tomshardware.com/reviews/intel-uefi-firmware,2486.html
cool beans
http://www.tomshardware.com/reviews/intel-uefi-firmware,2486-4.html
* Foxhoundz has quit (Ping timeout: 244 seconds)
quote: We switched on the UEFI boot feature in the system
setup menu of Intel???s DP55KG.
On-Board RAID: No Support for Bootable Partitions at > 2 TB
* godel_ (~gonzalo-at-190.191.221.239) has joined ##hardware
* Foxhound1 has quit (Ping timeout: 244 seconds)
that's a problem specific to the intel fakeraid, not even to
bios/uefi
* godel has quit (Ping timeout: 272 seconds)
and it shouldn't affect you on linux, since there's no benefit
to using fakeraid there
assuming he booted the cd with uefi
* Corey84- has quit (Excess Flood)
* ezekielnoob has quit (Quit: ezekielnoob)
* JewFro297______ (~JewFro297-at-cpe-74-77-203-235.buffalo.res.rr.com) has
* joined ##hardware
* Compgeke|T410 (~Compgeke-at-75.sub-70-197-5.myvzw.com) has joined
* ##hardware
* JewFro297 has quit (Ping timeout: 245 seconds)
* arescorpio has quit (Excess Flood)
* Foxhoundz (~Foxhoundz-at-unaffiliated/foxhoundz) has joined ##hardware
* oeuvre has quit (Read error: Connection reset by peer)
This looks nice: NZXT H440
every1 is using that now
it's like the flavor of the month
* veek (~veek-at-unaffiliated/veek) has joined ##hardware
* Krixvar has quit (Read error: Connection reset by peer)
I'm getting an SSD drive for my OS and a few programs to boot
on. :)
cool
* wagonboi has quit (Quit: Leaving)
I couldn't really afford one big enough to replace my HD, but
that should at least speed the OS a lot up. :)
I'm getting an Intel one, because they're known for good
firmware support.
I originally wanted to get a Samsung, but then I heard their
firmware is buggy and this creates problems.
supposedly their is a bug with the 840 evo
I have two though and im not having any issue
yeah, I was thinking of that one in particular.
it's good that you aren't having issues, but others are and I
didn't want to risk it.
they fixed that though I think
DF3D2: you should do a firmware update if samsung has patched a
bug
pretty quickly too
Kevin`, I have none available so Im guessing I got the fix
already
EXT0BB6Q
* Corey84- (Elite12618-at-gateway/shell/elitebnc/x-wfsadtfrckxkznof) has
* joined ##hardware
oh its an app you run
"samsung performance reastoration"
DF3D2, I'm glad to hear they fixed it. Still am kind of glad I
went with Intel tho... though this one has problems with TRIM for
deleted incompressible data, so maybe I'll get a different one for my
main drive if I upgrade that.
DF3D2: iirc that should just be for devices that were running
with the bug
EdLin, which one?
* Foxhound1 (~Foxhoundz-at-unaffiliated/foxhoundz) has joined ##hardware
Kevin`, well im guessing I had the bug, since I have an affected
drive
but I never did speed tests and didn't "notice" any issues so..
.but ill run the update just to be safe
DF3D2, the 530 I think it's called, and the Enterprise version
of that I got in a clearance sale, 2500 pro I think.
EdLin, cool I have a 160gb 330 I think. in one of my laptops I
never use
DF3D2, 730, their latest, doesn't have that bug - but if you're
putting it in a laptop (I'm not) it uses a lot of watts compared to
other SSD drives.
Sachiru - that is an excellent link you fed me. It doesn't
directly answer my BIOS question but it covers the UEFI in a great way.
I searched all over for something like that article
their latest comes at a premium though, it isn't a cheap drive.
mrbrklyn: have you seen the tool efibootmgr?
EdLin, didnt intel get out of the consumer ssd market?
There is one thing though, as part of a Architecture Class
mrbrklyn: aside from looking at that, be aware that the esp
MUST be the first partition on a drive
Kevin, maybe, probobly
* Foxhoundz has quit (Quit: Pulling out.)
DF3D2, nope. They just stopped making custom hardware for it, | |
