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Date:   Sat, 25 Jul 2020 20:56:49 +0200
From:   Joerg Roedel <joro@8bytes.org>
To:     Ingo Molnar <mingo@kernel.org>
Cc:     Thomas Gleixner <tglx@linutronix.de>, x86@kernel.org,
        Peter Zijlstra <peterz@infradead.org>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Andy Lutomirski <luto@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        linux-kernel@vger.kernel.org
Subject: Re: Regression on todays tip/master (commit 16f70beccf43)
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On Sat, Jul 25, 2020 at 12:38:50PM +0200, Ingo Molnar wrote:
> On a second thought, I think this recent bug might have been the 
> culprit:
> 
>   d136122f5845: ("sched: Fix race against ptrace_freeze_trace()")
> 
> Fixed in tip:sched/urgent - this is why it went away in your testing 
> perhaps?

Indeed, tip/master with this commit reverted triggers the issue again,
so it appears to be the same problem. But it leaves the question why I
couldn't trigger it with plain v5.8-rc6.

Thanks,

	Joerg