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Date:   Fri, 26 Jun 2020 16:20:34 +0100
From:   Steve McIntyre <steve@einval.com>
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     Jann Horn <jannh@google.com>,
        John Johansen <john.johansen@canonical.com>,
        Sasha Levin <sashal@kernel.org>, stable@vger.kernel.org,
        963493@bugs.debian.org
Subject: Re: Repeatable hard lockup running strace testsuite on 4.19.98+
 onwards
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On Fri, Jun 26, 2020 at 02:45:18PM +0100, Steve McIntyre wrote:
>Hey Greg,
>
>On Fri, Jun 26, 2020 at 03:41:32PM +0200, Greg KH wrote:
>>On Fri, Jun 26, 2020 at 12:35:58PM +0100, Steve McIntyre wrote:
>>> 
>>> e58f543fc7c0926f31a49619c1a3648e49e8d233 is the first bad commit
>>> commit e58f543fc7c0926f31a49619c1a3648e49e8d233
>>> Author: Jann Horn <jannh@google.com>
>>> Date:   Thu Sep 13 18:12:09 2018 +0200
>
>...
>
>>> Annoyingly, I can't reproduce this on my disparate other machines
>>> here, suggesting it's maybe(?) timing related.
>>> 
>>> Hope this helps - happy to give more information, test things, etc.
>>
>>So if you just revert this one patch, all works well?
>
>Correct.
>
>>I've added the authors of the patch to the cc: list...
>>
>>Also, does this problem happen on Linus's tree?
>
>Just building to check that now...

Current head here (3e08a95294a4fb3702bb3d35ed08028433c37fe6) works fine.

-- 
Steve McIntyre, Cambridge, UK.                                steve@einval.com
The two hard things in computing:
 * naming things
 * cache invalidation
 * off-by-one errors                  -- Stig Sandbeck Mathisen