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Date:   Thu, 25 Apr 2019 20:17:42 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc:     Borislav Petkov <bp@alien8.de>, Andy Lutomirski <luto@kernel.org>,
        Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org,
        x86@kernel.org, hpa@zytor.com,
        Thomas Gleixner <tglx@linutronix.de>,
        Nadav Amit <nadav.amit@gmail.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        linux_dti@icloud.com, linux-integrity@vger.kernel.org,
        linux-security-module@vger.kernel.org, akpm@linux-foundation.org,
        kernel-hardening@lists.openwall.com, linux-mm@kvack.org,
        will.deacon@arm.com, ard.biesheuvel@linaro.org,
        kristen@linux.intel.com, deneen.t.dock@intel.com,
        Nadav Amit <namit@vmware.com>
Subject: Re: [PATCH v4 04/23] x86/mm: Save DRs when loading a temporary mm
Message-ID: <20190425181742.GZ11158@hirez.programming.kicks-ass.net>
References: <20190422185805.1169-1-rick.p.edgecombe@intel.com>
 <20190422185805.1169-5-rick.p.edgecombe@intel.com>
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On Mon, Apr 22, 2019 at 11:57:46AM -0700, Rick Edgecombe wrote:
> From: Nadav Amit <namit@vmware.com>
> 
> Prevent user watchpoints from mistakenly firing while the temporary mm
> is being used. As the addresses that of the temporary mm might overlap
> those of the user-process, this is necessary to prevent wrong signals
> or worse things from happening.

Ooh, goody, that would be fun indeed.

> Cc: Andy Lutomirski <luto@kernel.org>

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

> Signed-off-by: Nadav Amit <namit@vmware.com>
> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>