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[209.132.180.67]) by mx.google.com with ESMTP id i16si2725707otk.112.2020.04.02.13.16.32; Thu, 02 Apr 2020 13:16:45 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=KBXKWSqm; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388650AbgDBUNg (ORCPT + 99 others); Thu, 2 Apr 2020 16:13:36 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:51153 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728225AbgDBUNf (ORCPT ); Thu, 2 Apr 2020 16:13:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1585858414; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=sEVid2/hqzCwbpXVjBCKhiCXLwn+Ox5cTajgLyA7oKE=; b=KBXKWSqmFT5u0p+UOC0EXaFhczTIHfxouC02Zc40tmch7l1EP5rlnQo/VLu3LuQNB9/4XH WsahDhcmaZW9Wvs5UDGweCwIWaQpsQHoUp7bZyez4IqQzvxtw8dBm9EYJPbnIkbfOII7uQ TlAuJgibVWJjnuhotAyB6L5qhvILfBI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-485-NVKHwL8nNTaO8UvSt3bvrw-1; Thu, 02 Apr 2020 16:13:33 -0400 X-MC-Unique: NVKHwL8nNTaO8UvSt3bvrw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 793508017CE; Thu, 2 Apr 2020 20:13:31 +0000 (UTC) Received: from treble (ovpn-118-100.rdu2.redhat.com [10.10.118.100]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3B8551001B09; Thu, 2 Apr 2020 20:13:30 +0000 (UTC) Date: Thu, 2 Apr 2020 15:13:28 -0500 From: Josh Poimboeuf To: Balbir Singh Cc: linux-kernel@vger.kernel.org, tglx@linutronix.de, tony.luck@intel.com, keescook@chromium.org, x86@kernel.org, benh@kernel.crashing.org, dave.hansen@intel.com Subject: Re: [PATCH 0/3] arch/x86: Optionally flush L1D on context switch Message-ID: <20200402201328.zqnxwaetpk4ubg56@treble> References: <20200402062401.29856-1-sblbir@amazon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200402062401.29856-1-sblbir@amazon.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 02, 2020 at 05:23:58PM +1100, Balbir Singh wrote: > Provide a mechanisn to flush the L1D cache on context switch. The goal > is to allow tasks that are paranoid due to the recent snoop assisted data > sampling vulnerabilites, to flush their L1D on being switched out. Hi Balbir, Just curious, is it really vulnerabilities, plural? I thought there was only one: CVE-2020-0550 (Snoop-assisted L1 Data Sampling). (There was a similar one without the "snoop": L1D Eviction Sampling, but it's supposed to get fixed in microcode). -- Josh