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Date:   Tue, 27 Oct 2020 18:56:17 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Andy Lutomirski <luto@kernel.org>
Cc:     Kyle Huey <me@kylehuey.com>,
        open list <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@kernel.org>,
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        "Paul E. McKenney" <paulmck@kernel.org>,
        Frederic Weisbecker <frederic@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Petr Mladek <pmladek@suse.com>,
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        Brian Gerst <brgerst@gmail.com>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Daniel Thompson <daniel.thompson@linaro.org>
Subject: Re: [REGRESSION] x86/debug: After PTRACE_SINGLESTEP DR_STEP is no
 longer reported in dr6
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On Tue, Oct 27, 2020 at 10:08:14AM +0100, Peter Zijlstra wrote:
> On Mon, Oct 26, 2020 at 04:30:32PM -0700, Andy Lutomirski wrote:
> > Is there any compelling reason not to just drop the condition and do:
> > 
> > current->thread.virtual_dr6 |= (dr6 & DR_STEP);
> > 
> > unconditionally?
> 
> Because why should it?

Because WINE does indeed rely on that. I'll go post a new version.