From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56471) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dnLr9-0007ml-Is for qemu-devel@nongnu.org; Thu, 31 Aug 2017 05:33:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dnLr6-0006qm-Fe for qemu-devel@nongnu.org; Thu, 31 Aug 2017 05:33:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39664) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dnLr6-0006q1-8c for qemu-devel@nongnu.org; Thu, 31 Aug 2017 05:33:44 -0400 Date: Thu, 31 Aug 2017 11:33:40 +0200 From: Cornelia Huck Message-ID: <20170831113340.7b437fa7.cohuck@redhat.com> In-Reply-To: <20170830163609.50260-4-pasic@linux.vnet.ibm.com> References: <20170830163609.50260-1-pasic@linux.vnet.ibm.com> <20170830163609.50260-4-pasic@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 3/9] s390x/css: be more consistent if broken beyond repair List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Halil Pasic Cc: Dong Jia Shi , Pierre Morel , qemu-devel@nongnu.org On Wed, 30 Aug 2017 18:36:03 +0200 Halil Pasic wrote: > If we detect that the internally manged state of the subchannel > is broken beyond repair while in do_subchannel_work in case of > virtual we just abort the operation and pretend all went well, > while in case of pass-through we honor the situation with -ENODEV > which results in cc 3 for the instruction whose handler triggered > the call. > > Let's be consistent on this and do the -ENODEV also for virtual > subchannels. > > Signed-off-by: Halil Pasic > Acked-by: Pierre Morel > --- > hw/s390x/css.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/hw/s390x/css.c b/hw/s390x/css.c > index 0822538cde..bc47bf5b20 100644 > --- a/hw/s390x/css.c > +++ b/hw/s390x/css.c > @@ -1078,7 +1078,7 @@ int do_subchannel_work_virtual(SubchDev *sch) > sch_handle_start_func_virtual(sch); > } else { > /* Cannot happen. */ > - return 0; > + return -ENODEV; No, this _really_ cannot happen. fctl is a three-bit field, which means that one of the branches above must have executed. fctl cannot be 0, as any caller of do_subchannel_work() either sets a bit there or, in the case of rsch, checks for a bit already set. This is an internal error, so an assert seems more suitable here. [We might need to keep the return to keep mingw happy.] > } > css_inject_io_interrupt(sch); > return 0;