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Date:   Thu, 14 May 2020 11:19:40 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        rostedt <rostedt@goodmis.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        x86 <x86@kernel.org>, paulmck <paulmck@kernel.org>,
        Andy Lutomirski <luto@kernel.org>,
        Alexandre Chartre <alexandre.chartre@oracle.com>,
        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>,
        "Joel Fernandes, Google" <joel@joelfernandes.org>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Juergen Gross <jgross@suse.com>,
        Brian Gerst <brgerst@gmail.com>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Will Deacon <will@kernel.org>
Subject: Re: [patch V4 part 1 05/36] x86/entry: Flip _TIF_SIGPENDING and
 _TIF_NOTIFY_RESUME handling
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On Wed, May 13, 2020 at 10:51:53PM -0400, Mathieu Desnoyers wrote:

> Yes, I'm very well aware of this. But the patch commit message states:
> 
> "Make sure task_work runs before any kind of userspace -- very much
> including signals -- is invoked."
> 
> which seems to imply that "userspace" can be "invoked" before the task_work
> runs. Which makes no sense whatsoever. Hence my confused state.

I initially missed the run_task_work in the signal handling maze. Then
later figured this order still made more sense, but apparently there's
an actual problem.

I've no problem with the patch getting dropped.