From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 418FDC433E3 for ; Sat, 11 Jul 2020 00:28:09 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id B224A207BB for ; Sat, 11 Jul 2020 00:28:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="rcoEfIMj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B224A207BB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 2C6E94B0CA; Fri, 10 Jul 2020 20:28:08 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@kernel.org Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Ly-6N23jG78H; Fri, 10 Jul 2020 20:28:07 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 194034B158; Fri, 10 Jul 2020 20:28:07 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 0DDDA4B152 for ; Fri, 10 Jul 2020 20:28:06 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ruQ0slE+lShk for ; Fri, 10 Jul 2020 20:28:04 -0400 (EDT) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 1A2114B0CA for ; Fri, 10 Jul 2020 20:28:04 -0400 (EDT) Received: from localhost (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 928E32078B; Sat, 11 Jul 2020 00:28:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594427282; bh=BRp8sZxnMGB3vpZ0E+ioDMibR1SlBT/gKwtr/pLNEYo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=rcoEfIMjSYOscAN4dOPiRCIwgHLNfsr7WG33Xmy4XgKSPX9fNs3pkh0AaMgqZdLtc LssjVDTYv0uJJtzW6DQThgD3hoW9QztI7ZtFZvf178SFjx1tBiMW5qHGFPnzn80fn4 gl3ywItY31zXbbTGkHz3MQJEXwCvCnACTvLT8/rI= Date: Fri, 10 Jul 2020 20:28:01 -0400 From: Sasha Levin To: Florian Fainelli Subject: Re: [PATCH stable v4.9 v2] arm64: entry: Place an SB sequence following an ERET instruction Message-ID: <20200711002801.GE2722994@sasha-vm> References: <20200709195034.15185-1-f.fainelli@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200709195034.15185-1-f.fainelli@gmail.com> Cc: Nick Desaulniers , Fangrui Song , Catalin Marinas , Will Deacon , open list , stable@vger.kernel.org, "open list:KERNEL VIRTUAL MACHINE FOR ARM64 \(KVM/arm64\)" , Mark Brown , Sami Tolvanen , Marc Zyngier , Kristina Martsenko , Will Deacon , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu On Thu, Jul 09, 2020 at 12:50:23PM -0700, Florian Fainelli wrote: >From: Will Deacon > >commit 679db70801da9fda91d26caf13bf5b5ccc74e8e8 upstream > >Some CPUs can speculate past an ERET instruction and potentially perform >speculative accesses to memory before processing the exception return. >Since the register state is often controlled by a lower privilege level >at the point of an ERET, this could potentially be used as part of a >side-channel attack. > >This patch emits an SB sequence after each ERET so that speculation is >held up on exception return. > >Signed-off-by: Will Deacon >[florian: Adjust hyp-entry.S to account for the label > added change to hyp/entry.S] >Signed-off-by: Florian Fainelli I've queued it up, thanks! -- Thanks, Sasha _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm