From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH v2 for-4.5] xen/arm: clear UIE on hypervisor entry Date: Thu, 20 Nov 2014 11:06:24 +0000 Message-ID: <546DCB30.6040400@linaro.org> References: <1416480804-25651-1-git-send-email-stefano.stabellini@eu.citrix.com> <546DCA3F.2030508@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <546DCA3F.2030508@linaro.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Stefano Stabellini , xen-devel@lists.xensource.com Cc: julien.grall@citrix.com, Ian.Campbell@citrix.com, andrii.tseglytskyi@globallogic.com List-Id: xen-devel@lists.xenproject.org On 11/20/2014 11:02 AM, Julien Grall wrote: > Hi Stefano, > > On 11/20/2014 10:53 AM, Stefano Stabellini wrote: >> UIE being set can cause maintenance interrupts to occur when Xen writes >> to one or more LR registers. The effect is a busy loop around the >> interrupt handler in Xen >> (http://marc.info/?l=xen-devel&m=141597517132682): everything gets stuck. >> >> Signed-off-by: Stefano Stabellini >> Reported-and-Tested-by: Andrii Tseglytskyi >> CC: konrad.wilk@oracle.com >> --- >> >> Konrad, this fixes an actual bug, at least on OMAP5. It should have no >> bad side effects on any other platforms as far as I can tell. It should >> go in 4.5. > > From Andrii's mail, there is a bad side effect. We can receive spurious > interrupt. > > On V1, you said that you tried this patch on midway. I would prefer if > you give a try on platform that would really be used (such as xgene or > seattle). As we know Midway won't be used in prod. And maybe give a try to gicv3 too as it's common code. Regards, -- Julien Grall