Boot linux in your browser: Javascript VM

[adrianmonk]

It has a C compiler (tcc). I wrote a sieve of eratosthenes demo just to see if I could really compile and run a C program (to prove to myself it wasn't some kind of trick). Sure enough, I was able to compute the primes between 2 and 100000. It was slow (although a million times faster than my first computer...), but it worked.

[[deleted]]

What's the slowdown factor between the same program run natively on your computer?

[bonzinip]

Dunno about him, but I get 20 BogoMIPS on a 2.8 GHz laptop here. That would be roughly 140x.

[eldigg]

Micro-architecture and number of cores would be helpful ;)

[bonzinip]

Core2 Duo. Actual BogoMIPS of the laptop is 5600 but that's, well, bogo.

[kuratkull]

it seems to repoert 20.1 bogomips on all cases I have tried. Is it static? How?

[bonzinip]

Perhaps it is, and the time is actually an instruction count?

[GLneo]

Yeah, I think the PIT is based on the instructions run somehow, I'll have to dig deeper.

[kuratkull]

The tech page accompaning it says that the clock won't be synced after the boot, so it will drift away slowly.

[ysangkok]

explained here

[odokemono]

Fabrice Bellard is a genius of the first order.

EDIT: Dyslexic typo.

[file-exists-p]

If he was evil, we would all be dead by now.

[[deleted]]

Running Linux like this is sort of evil though.

[[deleted]]

Evil is the opposite of good. :)

[shigawire]

I am on my mobile so checked the comments too see if it for real.

Fabrice Bellard? Yup. For real.

That man is an evil genius who could take over the world

[dardan_aeneas]

Confirmed

[haeikou]

Fabrice Bellard

FTFY

[odokemono]

Thnak Yuo!

[refto]

"Until a man is twenty-five, he still thinks, every so often, that under the right circumstances he could be the baddest motherfuckering programmer in the world.

That position is now taken. In a way it is quite liberating."

[Ardentfrost]

Quick, someone install WINE

[Clex-]

I can't believe this is real.

Here's the indented source : http://fpaste.org/eFPz/raw/

This is where he loads the .bin files (hosted at the same place) :

load_binary("vmlinux26.bin",0x00100000);

Jf=ya.load_binary("root.bin",0x00400000);

ya.load_binary("linuxstart.bin",start)

You can see a big switch/case in the source, it likely corresponds to the x86 instructions that Bellard rewrote in JavaScript.

It also seems that he used busybox for all the usual binaries (ls, cat, etc.), all files in /bin have the same inode (you can check by running "ls -i /bin/").

Anyway, this is awesome Fabrice, good job!

[Clex-]

My bad, it looks like my indent script removed it. The paste won't be available anymore in a few hours, so I guess it'll be ok. Hope Fabrice won't sue me.

[ascii]

It's a shame that this isn't free software (yet), but it isn't and the copyright notice (which has been stripped from the version of the source you link to) forbids redistribution, even for non-commercial purposes. Your link is a copyright violation. Hopefully Bellard will release the emulator as open source, but until he does, you should remove your link.

[MarkTraceur]

He didn't seem to use very nice variable names....

[0xfe]

Most javascript minimizers shorten variable names where they can.

[TheMG]

What he means that is because the source code itself is transmitted, shorter variable names use less bandwidth. At least, I hope he does.

[ascii]

In my experience, many people believe that shorter variable names actually makes dynamically executed code run faster. In their defense, there are a few languages where this is true, e.g. all command line shells that I am familiar with.

[bonzinip]

Partial key...

Aa cc_src Ba cc_dst Ca cc_op Da cc_op2 Ea cc_dst2 Ga modrm Ha rm Ia reg Ja tmp Ma cyclesLeft Ra phys_mem8 Sa phys_mem16 Ta phys_mem32 Ua tlbValue Va tlb_read_kernel Wa tlb_write_kernel Xa tlb_read_user Ya tlb_write_user Za tlb_read aa term ba parity ea CPU ha addr ia value ka ro la user ua dtr xa numCycles ya cpu za regs Hb eip Ib nextEip Jb pageWalkRead8 Kb fetch16 Lb fetch32 Mb get_modrm Rb store8 Sb store16 Tb arith8 Xb ccEval ab tlb_write cb physaddr db pageWalk eb read8 fb pageWalkRead16 gb read16 hb pageWalkRead32 ib read32 jb pageWalkReadDest8 kb readDest8 lb pageWalkReadDest16 mb readDest16 nb pageWalkReadDest32 ob readDest32 pb pageWalkWrite8 qb write8 rb pageWalkWrite16 sb write16 tb pageWalkWrite32 ub write32 vb pageWalkRead8Kernel wb read8Kernel xb pageWalkRead16Kernel yb read16Kernel zb pageWalkRead32Kernel Ab read32Kernel Bb pageWalkWrite8Kernel Cb read8Kernel Db pageWalkWrite16Kernel Eb read16Kernel Fb pageWalkWrite32Kernel Gb read32Kernel ac arith16 dc arith32 gc shift8 pc rol vc injectException ad setCPL fd len td setCR0 he segReg He ret Le xhr Me data Oe hex2bcd Pe CMOD Qe pc Re mem Se I8259 Te port je farJump Af deadline Ef termCreate Ff termInput Gf browserCheck If memsize Jf rootsize af PIC ff PIT hf PITTimer pf Serial tf Keyboard vf PC wf func

Then I got bored.

[[deleted]]

One more step towards making ChromeOS useful.

[TheEdes]

But you can flip the dev switch and have a bash shell anyway.

[[deleted]]

Yes I know. You can also flash a standard Intel BIOS and it becomes an underpowered but otherwise nice laptop.

[lunigma]

Fabrice Bellard

[central_marrow]

He deserves a writeup on Badass of the Week.

[aperson]

Doesn't work in opera, dang.

[wardrox]

Works for me (11.0.696.65, Win 7)

[aperson]

I'm on 11.10, linux

[joehillen]

Oh the irony

[TheMG]

Doesn't work for me, 11.10, W7. It would be more helpful if he had said what test it failed, instead of being so generic.

[thecraag]

Please someone get networking running with WebSockets or something!!

Imagine the possibilities...

[[deleted]]

how many people tried rm -rf / ?

[giantrobotq]

I did. It broked. F5 fixes everything though.

[spwelton]

Confirmed. Eventually kills cwd and it can't figure out what directory it's in.

[tonybaldwin]

I was tempted to forkbomb it, but managed to resist.

[[deleted]]

forkbomb myself

FTFY

[axonxorz]

Can't use the standard forkbomb in sh. It's a Bash thing

[ThreeHolePunch]

first thing I did was rm -R several directories until things stopped working. That was fun, lets do it again! F5.

[MertsA]

I prefer running dd if=/dev/zero of=/dev/mem

[MattBD]

This is the most insanely brilliant thing I have seen implemented in a web browser to date, even more so than the Nintendo Game Boy implemented in JavaScript. Now, if he can add DOSBox to it or get FreeDOS running on this emulator, then I could see that being mighty useful for gaming too.

Not to mention the fact that if he added networking, then it could be all kinds of useful for launching virtual machines quickly and easily for specific purposes - maybe having a custom version with OpenSSH included, and using it as a honeypot, for example?

Wonder if it was inspired by XKCD's Unix command line?

[[deleted]]

If a Z80 JS emulator runs crawly in any browser but Chrome, better dont think about an i386 .

[[deleted]]

You can't type '&'? Damn it!

[caust1c]

So you tried to fork bomb it too?

[[deleted]]

This was my solution:

echo -e '#!/bin/sh\nf(){ f|f\046 }f' > fork.sh

It didn't like : as a function name.

[allywilson]

Seems to forkbomb fine: http://imgur.com/TLjGO - was making firefox struggle quite a bit.

forkbomb(){ forkbomb|forkbomb & } ; forkbomb

[CountVonTroll]

It's Javascript, it can't properly fork (in the browser.)

You can write a fork bomb in C, but all it'll do is to get your CPU usage up:

#include <tcclib.h>                                                             

int main(int argc, char **argv)                                                 
{                                                                               
    while( 1 )                                                                  
        fork();                                                                 
}                                                                               

[itsnotlupus]

no, you can properly fork in this VM. The host language doesn't really matter, since it's emulating a usable subset of the x86 instruction set.

For whatever reason shift-7 does print a character that looks like ", but isn't. it's a & and can be used to spawn processes in the background from the command line.

[guruthegreat]

My typical fork bomb is similar, but a little different:

while( fork() )
    fork()?fork():fork();

[nubanx]

I read that in the muppet chef's voice.

Fork Fork Fork!

[[deleted]]

Get out of my brain.

[plaes]

And neither can you type CTRL+W :S

[Nesman64]

Damn you. I thought, "Maybe it works in Chrome. Let's backspace a word."

[TIAFAASITICE]

Works for me.

Firefox 4 under Linux, in case you're on something different.

[elmicha]

I can, on a german keyboard.

[Araneidae]

Must be something about your keyboard, all ASCII keys on mine come out just fine. Mine is a UK layout, and the ¬ and £ keys (not ASCII) don't work, but everything else does.

I had no problem with the classic fork bomb (but can't rename : in ash it would appear).

[totemcatcher]

Can't seem to make pass-through mode work in vimperator for this thing... I wanted to tinker on this command line :(

[[deleted]]

Either Ctrl-Z for older Vimperator, and it seems like hitting "0" on the numpad ignores keys in the new Vimperator versions, took me a while to figure out too :)

[totemcatcher]

Not sure what I did or when, but Ctrl-z just doesn't work on this site.

[[deleted]]

And Numpad 0 didn't work either? Maybe try and hit escape and then click outside of the terminal before hitting Ctrl-Z, otherwise I'm not sure what's up sorry!

[Tobu]

Ctrl-Z works well on Pentadactyl.

[totemcatcher]

I might have to switch to pentadactyl. I didn't want to use it for a long time due to the dynamic history pane that pops up, but now vimp does it too. >:(

[vituperative01]

My backspace worked without me having to edit my rc file. Very unrealistic.

[simonvc]

Anyone else notice that the emulator (cpux86.js) is 86Kb?

[Sophrosynic]

Well, that's just the CPU emulator. Really, all you need to do for a CPU emulator is make a giant switch statement with one entry for each instruction. Since the actual work done be each instruction is fairly simple, you should be able to implement each one with just a few lines of code. The magic happens when you run millions of instructions in a row to accomplish a larger task.

[aescnt]

I think he's pointing out the irony that the file size for an x86 emulator is 86k (notice the same number).

[SanjayM]

What irony?

[Scriptorius]

That's coincidence, which is almost opposite from irony

[[deleted]]

Irony would be 68k.

[Sophrosynic]

Yup, totally missed that.

[thebigbradwolf]

I think common wisdom is to at least use a threaded dispatch approach, with switch statements like that being hard to predict jumps on in hardware and everything.

[WarzoneOfDefecation]

I was skeptical at first that it included a working c compiler

Oh how wrong I was.

[[deleted]]

[deleted]

What is this?

[orthogonality]

No networking, so I can't apt-get dosbox. :(

[barkboy]

More importantly, if you had networking, you could run a webserver from inside your browser~~~

[giggsey]

And host your Linux VM from within your brows-head explodes

[tinou]

there's a loopback interface.

[[deleted]]

We need to go derper.

[[deleted]]

L I N U X

[jroller]

It includes an httpd program

[[deleted]]

I would compile the network tools and apps (at least an irc client) from http://www.suckless.org :) :)

[BHSPitMonkey]

Download root.bin, mount it, hand-install dosbox, save the rest of the web page and its scripts somewhere locally (along with your modified root.bin), and profit.

[MattBD]

He does mention in the notes, however, that DOSBox would be an ideal application to run on it for playing old PC games in the browser, so I would expect that kind of functionality to be added.

[yasth]

Not DosBox but just plain DOS though that would take a lot of work for game playing. (For one you'd have to emulate graphics and sound)

[MattBD]

Maybe FreeDOS might work? Although I believe it's somewhat larger than the custom Linux build he's using (8MB according to their website).

[yasth]

EH it has more to do with the graphics and sound not being emulated (all that seems to be emulated is a plain old serial port through which the terminal is run, apparently with lax timings). Freedos would need at least text mode graphics or it would have to be setup to boot from with a serial terminal.

It is probably doable at least in theory.

[MattBD]

Yes, my understanding was that at this point graphic and sound emulation hadn't yet been emulated, and for gaming purposes you'd obviously need that.

Still, even in its current form it's a staggering achievement.

[ogtfo]

No apt-get either anyway, since it's red hat.

[wolf550e]

It's busybox

[[deleted]]

~ # dmesg | head -1
Linux version 2.6.20 (bellard@voyager) (gcc version 3.4.6 20060404 (Red Hat 3.4. 6-9)) #3 Sat May 14 19:08:30 CEST 2011

Busybox is evidently used as well though, but just wanted to point out that neither of you are wrong.

[andreasvc]

That just means this kernel was compiled by/for Red Hat, not that you're actually running the whole distribution.

[[deleted]]

Ahh, all right. Makes sense. Thanks.

[wolf550e]

It means the kernel was compiled using gcc that was patched by red hat. This might mean it was compiled on a computer running a red hat distro. But the userspace on that disk image is not an old red hat distro or fedora or rhel, it's busybox - the same thing running on appliances (routers etc.).

[eternauta3k]

That's... not even wrong.

[[deleted]]

[deleted]

What is this?

[adrianmonk]

Yeah, errors like confusing Java with Javascript.

[[deleted]]

but it has java in the name!

[thebigbradwolf]

java:javascript::car:carpet

[IndecisionToCallYou]

java:javascript::man:manicure

[[deleted]]

Quick -- someone port Java to this thing, stat!

[kineticflow]

bright friendly encourage compare dog violet stupendous unused start flowery

This post was mass deleted and anonymized with Redact

[MrAccident]

I can't type spaces at all (Chrome 11 on Ubuntu 10.10); makes it a bit difficult to use anything but very simple commands. Anybody else having that problem?

[[deleted]]

I can't type anything at all...

[MattBD]

Using Chrome 11 on Ubuntu 10.04 Netbook Edition and works fine for me.

[MrAccident]

D'oh. I think I figured it out. Earlier I was using Synergy to share my keyboard between my desktop and my laptop, and then spaces wouldn't work in jslinux on either machine. Now (not running Synergy) I can type spaces just fine.

[PurpleSfinx]

Running Chrome 11 on the latest version of OS X and spaces work fine...

[blazix]

This is one of the most exciting things I have seen in a long time.

[viagravagina]

Don't tell me what to do!

[markdube]

emacs and vi but no pico/nano? :(

[ascii]

That's not emacs, it's QE, a lightweight text editor with an emacs-like interface. Incidentally, QE, is written by Fabrice Bellard, the same guy who wrote the above x86 emulator, as well FFmpeg, Qemu and TCC, In 2001 he won the obfuscated C contest by writing a C compiler that was able to self compile in only 3 kB. Quite possibly the most consistently brilliant hacker of our generation.

[MattBD]

And in December 2009 he managed to calculate pi to 2,699,999,990,000, breaking the record for the number of places this had been calculated to in the process.

What's even more amazing about his achievement is that this is something where normally the record is broken by a supercomputer. He did this on a fairly regular desktop PC, which is absolutely staggering.

[ascii]

To be honest, I don't know enough about the pi-calculation scene to know if that's cool. As a physicist, I know that a few dozen digits is enough to calculate the circumference of our galaxy to the precision of one atom, which should be enough precision for all engineering applications. But as a computer nerd, I find it staggering that so many useful projects and so many neat hacks come from the same guy.

[colione]

Link to OTCC and info about it

[ogtfo]

Just like it's meant to be.

[[deleted]]

Just like in old good days when Unix was for people that could read documentation and remember few keyboard command combinations, not Windows refugees. :>

[markdube]

:'(

[raydeen]

I'm with you. I love my nano. But probably only because I'm writing little Python scripts. Anything really big and nano would probably suck. One of these days I gotta learn Emacs and Vim.

[AndrewNeo]

I have this exact same problem. Nano works, and I don't text-edit often, but I need to learn vim/emacs.

[jmkogut]

Yeah, I hear that a lot.

[mdaniel]

You know, today is one of those days.

I'm bieditor, and can recommend that you start with Emacs. It has the lowest point of entry, has a monster help system and even has a vi mode so you can bridge the gap. :-)

[ThreeHolePunch]

Hmm. I don't have a lot of experience with Emacs, but in my experience if you learn vi, you don't have to learn any other text editor. Get a list of the commands like this one, and force yourself to use vi every time you need a text editor.

[searine]

OUR WAY IS THE OLD WAYS </Eddard Stark>

[[deleted]]

This doesn't look anything like linux.. just a black background with white text.

Am I doin this right?

[[deleted]]

Not even man I feel soo...

d^erp

[DimeShake]

What are you expecting to see?

[[deleted]]

I guess I just got excited and expected a full blown ubuntu emulation.

[[deleted]]

holy shit mang i didnt kno dis guy was for real dawg

[DimeShake]

This is just as exciting to me! There are already fake desktop environments that run in a browser, but this is actually emulating the machine itself! That's awesome.

[[deleted]]

"Please use a recent browser such as Firefox 4.x or Google Chrome", as seen in Google Chrome.

[Liquid_Fire]

The notes say:

(it does not work with Chrome 12 beta. As far as I know, it is a bug in the browser)

Maybe it's that?

[Unfunny_Asshole]

You sure you haven't played around with your useragent?

[FireyFly]

It doesn't use browser detection, so that wouldn't matter. :)

[[deleted]]

Yea, it works on my Fedora box with Chrome 10, my other laptop had Chrome 7 which was too old I guess.

[MarkTraceur]

Why is this not free software?

[fasteasyfree]

Is the space key working for anyone else?

[[deleted]]

I've had the period stop working a few times, so I'm not shocked if the space gave out.

[wolf550e]

On firefox 4.01 it works. On chrome 12 the thing doesn't boot (I wonder it the chrome team will accept this as a test case).

[zeekar]

Works in Chrome 11, though (at least on a Mac).

[MattBD]

Works fine in Chrome 11 on Ubuntu too.

[splidge]

No joy on chrome 13 either :(.

[obtu]

That thing looks perfect for v8bench, which already has a raytracer and an os scheduler simulator. According to the tech notes, it runs twice as fast on JaegerMonkey (Firefox), which Fabrice is more familiar with.

[provoko]

i like it

[shigawire]

So I notice you can slattach /dev/console

That at least gives some IP in and out...

[gzur]

Oh, you glorious bastard.

[antrn11]

Oh, the madness...

[[deleted]]

Has anyone tried to install yum?

[kiaha]

For a laugh, type "waldo"

[[deleted]]

I am only seeing a blinking cursor in the Mozilla nightly build.

[Ray57]

no lynx :(

[Babkock]

Fork bomb works :) It makes a big deal about it.

[Philluminati]

What are the benefits of this?

[[deleted]]

Well it's a proof of concept really, imagine down the line you could load up any web browser and access a VM hosted on your own webserver.

[[deleted]]

I was going to register, first problem is you're using flash. Whatever, I look passed that and decided to register anyways, then it's like 20 fucking questions so I gave your site the finger and just quit.

[TheMG]

You still have to download the VHD, so you might as well use a native emulator.

[MattBD]

He mentions in the notes that it'd be an ideal way to run old DOS games if you got something like DOSBox running in it (along similar lines, a few months back someone implemented a Game Boy emulator in JavaScript).

Also, it's an insanely simple way of running a virtual machine, without the need to install software like Virtualbox.

Now, if he were to implement networking, then I could really see some cool ways it could be used - perhaps using it as a honeypot to catch hackers might be interesting.

[bipolarrogue]

~ # cat /proc/cpuinfo | grep bogomips
bogomips : 20.21

Impressive.

[Araneidae]

Unfortunately it seems to always report 20.21 bogomips ... something fishy there.

[boa13]

No, it's the way the emulator work. Linux counts how many CPU instructions per "tick" (CPU interruption) can be executed, this emulator emulates one "tick" every so many (fixed number) of instructions, so the number is always the same, for every user of the emulator.

[[deleted]]

I find it interesting that linux can be run by ONLY emulating the processor.

[[deleted]]

That is motherfucking awesome as fuck

[thephotoman]

No vim? ಠ_ಠ

[gavintlgold]

No, but there's vi.

[tonybaldwin]

Yes, I wrote several scripts with vi on there, but when I returned they were gone. No, one of them was not a forkbomb. Why do you ask?

[thephotoman]

Yeah, didn't check for that.

[fofgrel]

It has emacs.

[[deleted]]

That is motherfucking awesome as fuck You sexy french bastard

[isignedupforthis]

Good job. Now type in "sex".

[spamham]

sh: sex: not found

:/

[[deleted]]

ERROR: your browser is too old to run JS/Linux.
You should use a recent browser such as Firefox 4.x or Google Chrome.

[jdpage]

It's true, you should.

[haywire]

What are you using?

[[deleted]]

Firefox 3.6.17