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Subject: Re: WARNING in is_bpf_text_address
To:     Will Deacon <will@kernel.org>,
        syzbot <syzbot+bd3bba6ff3fcea7a6ec6@syzkaller.appspotmail.com>
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From:   Bart Van Assche <bvanassche@acm.org>
Message-ID: <456d0da6-3e16-d3fc-ecf6-7abb410bf689@acm.org>
Date:   Thu, 15 Aug 2019 18:39:56 -0700
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On 8/15/19 12:51 AM, Will Deacon wrote:
> Hi Bart,
> 
> On Sat, Aug 10, 2019 at 05:24:06PM -0700, syzbot wrote:
>> syzbot has found a reproducer for the following crash on:
>>
>> HEAD commit:    451577f3 Merge tag 'kbuild-fixes-v5.3-3' of git://git.kern..
>> git tree:       upstream
>> console output: https://syzkaller.appspot.com/x/log.txt?x=120850a6600000
>> kernel config:  https://syzkaller.appspot.com/x/.config?x=2031e7d221391b8a
>> dashboard link: https://syzkaller.appspot.com/bug?extid=bd3bba6ff3fcea7a6ec6
>> compiler:       clang version 9.0.0 (/home/glider/llvm/clang
>> 80fee25776c2fb61e74c1ecb1a523375c2500b69)
>> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=130ffe4a600000
>> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17137d2c600000
>>
>> The bug was bisected to:
>>
>> commit a0b0fd53e1e67639b303b15939b9c653dbe7a8c4
>> Author: Bart Van Assche <bvanassche@acm.org>
>> Date:   Thu Feb 14 23:00:46 2019 +0000
>>
>>      locking/lockdep: Free lock classes that are no longer in use
>>
>> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=152f6a9da00000
>> final crash:    https://syzkaller.appspot.com/x/report.txt?x=172f6a9da00000
>> console output: https://syzkaller.appspot.com/x/log.txt?x=132f6a9da00000
> 
> I know you don't think much to these reports, but please could you have a
> look (even if it's just to declare it a false positive)?

Hi Will,

Had you already noticed the following message?

https://lore.kernel.org/bpf/d76d7a63-7854-e92d-30cb-52546d333ffe@iogearbox.net/

 From that message: "Hey Bart, don't think it's related in any way to 
your commit. I'll allocate some time on working on this issue today, 
thanks!"

Bart.