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Subject: Re: [PATCH v1 8/8] block: add add_disk() failure injection support
To:     Luis Chamberlain <mcgrof@kernel.org>,
        Brendan Higgins <brendanhiggins@google.com>,
        Akinobu Mita <akinobu.mita@gmail.com>
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From:   Hannes Reinecke <hare@suse.de>
Message-ID: <989175a7-5533-02ef-c096-b24b2769c9cf@suse.de>
Date:   Wed, 12 May 2021 19:55:25 +0200
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On 5/12/21 6:56 PM, Luis Chamberlain wrote:
> On Wed, May 12, 2021 at 05:22:48PM +0200, Hannes Reinecke wrote:
[ .. ]
>> So I'd rather delegate the topic of error injection to a more general
>> discussion (LSF springs to mind ...), and then agree on a framework which is
>> suitable for every function.
> 
> Or we just get cranking and produce proof of concepts to compare and
> contrast later. At least I hope this patch and the respective blktests
> patches suffice to help demo what we need to test.
> 
Yeah; I know; 'tis a hard topic.
(Will we have another ALPSS this year? Would be ideal to discuss things 
there. Christoph?)

What I would love to see is to facilitate kernel live patching for 
testing, blanking out the function body under test and just return 
specific error codes.
That would be _ideal_ for testing, as we don't have to modify the kernel 
at all, we just need to compile it with the appropriate compiler options 
for live patching.
And then we should be able compile modules for the functions to test, 
load the module, do the test, remove the module, and everything would be 
back to normal again.

I know, but one can dream ...

But maybe I can trick you in trying it ... hmm?

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
hare@suse.de                              +49 911 74053 688
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