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Date:   Tue, 16 Jun 2020 15:27:05 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Andy Lutomirski <luto@amacapital.net>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        kernel test robot <rong.a.chen@intel.com>,
        Alexandre Chartre <alexandre.chartre@oracle.com>,
        Andy Lutomirski <luto@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, lkp@lists.01.org,
        ltp@lists.linux.it
Subject: Re: [x86/entry] 2bbc68f837: ltp.ptrace08.fail
Message-ID: <20200616132705.GW2531@hirez.programming.kicks-ass.net>
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 <8E41B15F-D567-4C52-94E9-367015480345@amacapital.net>
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On Tue, Jun 16, 2020 at 06:22:10AM -0700, Andy Lutomirski wrote:
> 
> > On Jun 16, 2020, at 1:44 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
> > 
> > ﻿kernel test robot <rong.a.chen@intel.com> writes:
> >> FYI, we noticed the following commit (built with gcc-9):
> >> 
> >> commit: 2bbc68f8373c0631ebf137f376fbea00e8086be7 ("x86/entry: Convert Debug exception to IDTENTRY_DB")
> >> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
> > 
> > Is the head of linux.git exposing the same problem or is this an
> > intermittent failure, which only affects bisectability?
> 
> It sure looks deterministic:
> 
> ptrace08.c:62: BROK: Cannot find address of kernel symbol "do_debug"

ROFL