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Subject: Re: kernel panic: corrupted stack end in wb_workfn
To:     Dmitry Vyukov <dvyukov@google.com>
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From:   Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Message-ID: <a06830e7-e396-6dd5-d9d5-2a7b1df9efc1@i-love.sakura.ne.jp>
Date:   Wed, 20 Mar 2019 19:58:48 +0900
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On 2019/03/20 19:42, Dmitry Vyukov wrote:
>> I mean, yes, I agree, kernel bug bisection won't be perfect. But do
>> you see anything actionable here?

Allow users to manually tell bisection range when
automatic bisection found a wrong commit.

Also, allow users to specify reproducer program
when automatic bisection found a wrong commit.

Yes, this is anti automation. But since automation can't become perfect,
I'm suggesting manual adjustment. Even if we involve manual adjustment,
the syzbot's plenty CPU resources for building/testing kernels is highly
appreciated (compared to doing manual bisection by building/testing kernels
on personal PC environments).

> 
> I see the larger long term bisection quality improvement (for syzbot
> and for everybody else) in doing some actual testing for each kernel
> commit before it's being merged into any kernel tree, so that we have
> less of these a single program triggers 3 different bugs, stray
> unrelated bugs, broken release boots, etc. I don't see how reliable
> bisection is possible without that.
> 

syzbot currently cannot test kernels with custom patches (unless "#syz test:" requests).
Are you saying that syzbot will become be able to test kernels with custom patches?