From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH] xen/arm: ctxt_switch: Document the erratum #852523 related to Cortex A57 Date: Fri, 9 Oct 2015 11:40:30 +0100 Message-ID: <5617999E.4020804@citrix.com> References: <1444332157-22325-1-git-send-email-julien.grall@citrix.com> <1444382551.1410.309.camel@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1ZkV7d-00067d-2o for xen-devel@lists.xenproject.org; Fri, 09 Oct 2015 10:41:57 +0000 In-Reply-To: <1444382551.1410.309.camel@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell , xen-devel@lists.xenproject.org Cc: stefano.stabellini@eu.citrix.com List-Id: xen-devel@lists.xenproject.org On 09/10/15 10:22, Ian Campbell wrote: > On Thu, 2015-10-08 at 20:22 +0100, Julien Grall wrote: >> When restoring the system register state for an AArch32 guest at EL2, >> writes to DACR32_EL2 may not be correctly synchronised by Cortex-A57, >> which can lead to the guest effectively running into unexpected domain >> faults. >> >> Thankfully, we don't hit this erratum in Xen. Nonetheless, document the >> code to prevent any introduction of the erratum if the context switch >> code is re-ordered. >> >> Link: http://lists.xen.org/archives/html/xen-devel/2015-09/msg01746.html >> Signed-off-by: Julien Grall > > Acked-by: Ian Campbell > > nits: >> >> + /* >> + * This write to sysreg CONTEXTIDR_EL1 ensure we don't hit the erratum > > "ensures" and s/the //. > > (fixable on commit) I'm fine if you fix it while committing. Regards, -- Julien Grall