Re: [Pharo-dev] Code retrieval on primitive failed

Hi Vincent, On Thu, Dec 4, 2014 at 7:39 AM, Blondeau Vincent < vincent.blondeau@worldline.com> wrote:

Finally, I succeeded to retrieve my code !

I tried with the Cog VM Simulator to open my image.

It opened my crashed image in the simulator without any problem (it seems that the failing primitive has been caught).

But I cannot interact with the image through the simulator workspace and the morph.

It seems that you can launch some code by doit to export a package named MyPackage:

cos systemAttributes

at: 2 put: '-doit';

at: 3 put: (‘RPackage named:’’MYPackage’) fileout ’]

But this did not work because my code contains shared pools and it cannot be filed out…

In parallel, I tried the other solution of Clement by changing the bytecode in the .image itself.

If the problem comes from a native boost primitive, you should use a cogvm : (e.g. http://www.mirandabanda.org/files/Cog/VM/VM.r3056/cogwin-14.29.3056.zip) to launch the failing image.

After that, you should see the crash log and see which are the code that is failing (apparently one of the top method in the stack).

The best is to have the Smalltalk code of this method because you have to retrieve the associated bytecode. Else either you try to remember exactly the content of the method or you take another method in the stack where you have the code.

Once you have identified the method, extract the bytecode:

on Pharo4 with the right click on the method name and by printing ‘self bytecode hex’

on Pharo3 inspect the class containing the method, find the right compiled method and print ‘self bytecode hex’

After that open the broken image with a hexadecimal editor (I use HxD under w7) (do a COPY before).

Find the bytecode of the method and replace it by several 120 (78 in hex).

As the bytecodes are not unique, it is possible to do several replacements. If you don’t want that, you can find another bytecode available in the stack trace. Longest is the bytecode, less will be the number of finding matches.

Try to reopen your image with the cogwm. If it doesn’t work either you broke a critical method of your image (so try again with another bytecode) either you have another failure so you start again to find the good method.

You make me proud!! That's a great way to do it. Brings back memories of similar holes I'v dug for myself and crawled out of. Well done!

Once you can open it. Save your code!!!

The file out didn’t work for me so I commited with Monticello in local and it worked!

So don’t forget to commit!

Vincent

*De :* Blondeau Vincent *Envoyé :* mercredi 3 décembre 2014 18:41 *À :* Pharo Development List *Objet :* RE: [Pharo-dev] Code retrieval on primitive failed

*De :* Pharo-dev [mailto:pharo-dev-bounces@lists.pharo.org <pharo-dev-bounces@lists.pharo.org>] *De la part de* Clément Bera *Envoyé :* mercredi 3 décembre 2014 17:54 *À :* Pharo Development List *Objet :* Re: [Pharo-dev] Code retrieval on primitive failed

Please send the full stack trace. You don't have only three lines, do you ?

No, indeed (the full stack is attached).

There's one solution that Igor does sometimes that you can try...For that you need to remember what code you changed that now crashes the image in smalltalk. Do you know what code crash your image ?

Could you rewrite it (exactly the same code) in a fresh image ?

If so the process is as follow:

- rewrite the crashing code in a fresh image

- extract the bytecode from the compiled method

- open a copy of your image with an hexadecimal editor, look for the bytecode pattern, replace it by returnself (byte 120 the number of times needed)

- try open your copy. Do as little things as possible (typically, only file out your packages, monticello will most probably not work)

Ok I will try this but this is more a generic printing method that is the problem (see trace)… And not a specific method…

I tried but it seems not adapted to my case…

The alternative is to open your image on top of the cog simulator. Word has been that there's a Pharo 3 image running the cog simulator, you can use that to debug the code and fix it. Alternatively use a squeak vmmaker image that you can build with this script:

$ svn co http://www.squeakvm.org/svn/squeak/branches/Cog/image

$ cd ./image

$ ./buildsqueaktrunkvmmakerimage.sh

You put a halt on the implementation of primitive 117 in the simulator (named primitives call such as NB calls) to catch the crash and fix it from there in the simulator.

That seems better ! I am trying this way.

Good luck and have fun :-)

Thanks :)

2014-12-03 17:04 GMT+01:00 Blondeau Vincent < vincent.blondeau@worldline.com>:

Hello everyone,

I am doing some developments with NativeBoost and unfortunaly I succeed to save my image in a unstable state.

I am using the last moose image i.e.: Pharo3.0 - Latest update: #30860.

So when I want to launch my image, I get a primitive faillure.

The interesting part of the stack trace is :

Stack backtrace:

[07EE7A1B] ??? + 0 in (null)

[00539AB5] ??? + 1284789 in Pharo.exe

Smalltalk stack dump:

0x2410b8 M NBFFICallout class(NBNativeCodeGen class)>retrySend: 0x4c70b4c: a(n) NBFFICallout class

0x2410ec I NBFFICallout class(NBNativeCodeGen class)>retrySend: 0x4c70b4c: a(n) NBFFICallout class

0x78a0d90 s RDoubleVector(OrderedCollection)>at:

Then I wanted to retrieve my changes on a new image but, as the doIts are not recorded, I have neither the method deletions nor all the operations on classes nor the trait methods that are recorded as Doits with preamble: Trait method.

I tried to launch my image with squeak (which doesn’t support NativeBoost) to hope saving or commit my code. But as I am calling a primitive at startup of the image to initialize the external environement. I got the following trace :

[31m==== Startup Error: PrimitiveFailed: primitive #isEnabled in NativeBoost class failed

[0mNativeBoost class(Object)>>primitiveFailed:

NativeBoost class(Object)>>primitiveFailed

NativeBoost class>>isEnabled

NativeBoost class>>forCurrentPlatform

NativeBoost class>>loadSymbol:fromModule:

RSession class(Object)>>nbGetSymbolAddress:module:

So what can I do to retrieve all my code without loose a day to rewrite it?

Thanks in advance

Vincent

------------------------------

Ce message et les pièces jointes sont confidentiels et réservés à l'usage exclusif de ses destinataires. Il peut également être protégé par le secret professionnel. Si vous recevez ce message par erreur, merci d'en avertir immédiatement l'expéditeur et de le détruire. L'intégrité du message ne pouvant être assurée sur Internet, la responsabilité de Worldline ne pourra être recherchée quant au contenu de ce message. Bien que les meilleurs efforts soient faits pour maintenir cette transmission exempte de tout virus, l'expéditeur ne donne aucune garantie à cet égard et sa responsabilité ne saurait être recherchée pour tout dommage résultant d'un virus transmis.

This e-mail and the documents attached are confidential and intended solely for the addressee; it may also be privileged. If you receive this e-mail in error, please notify the sender immediately and destroy it. As its integrity cannot be secured on the Internet, the Worldline liability cannot be triggered for the message content. Although the sender endeavours to maintain a computer virus-free network, the sender does not warrant that this transmission is virus-free and will not be liable for any damages resulting from any virus transmitted.

------------------------------

Ce message et les pièces jointes sont confidentiels et réservés à l'usage exclusif de ses destinataires. Il peut également être protégé par le secret professionnel. Si vous recevez ce message par erreur, merci d'en avertir immédiatement l'expéditeur et de le détruire. L'intégrité du message ne pouvant être assurée sur Internet, la responsabilité de Worldline ne pourra être recherchée quant au contenu de ce message. Bien que les meilleurs efforts soient faits pour maintenir cette transmission exempte de tout virus, l'expéditeur ne donne aucune garantie à cet égard et sa responsabilité ne saurait être recherchée pour tout dommage résultant d'un virus transmis.

This e-mail and the documents attached are confidential and intended solely for the addressee; it may also be privileged. If you receive this e-mail in error, please notify the sender immediately and destroy it. As its integrity cannot be secured on the Internet, the Worldline liability cannot be triggered for the message content. Although the sender endeavours to maintain a computer virus-free network, the sender does not warrant that this transmission is virus-free and will not be liable for any damages resulting from any virus transmitted.

-- best, Eliot