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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ED14AC87FD3 for ; Fri, 8 Aug 2025 10:46:01 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ukKau-0007bf-0O; Fri, 08 Aug 2025 06:45:04 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ukKar-0007Zy-Td for qemu-devel@nongnu.org; Fri, 08 Aug 2025 06:45:01 -0400 Received: from [185.176.79.56] (helo=frasgout.his.huawei.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ukKao-0003dB-61 for qemu-devel@nongnu.org; Fri, 08 Aug 2025 06:45:01 -0400 Received: from mail.maildlp.com (unknown [172.18.186.231]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4bz0sd1yXpz6GD6h; Fri, 8 Aug 2025 18:40:05 +0800 (CST) Received: from frapeml500008.china.huawei.com (unknown [7.182.85.71]) by mail.maildlp.com (Postfix) with ESMTPS id D76FD14038F; Fri, 8 Aug 2025 18:44:43 +0800 (CST) Received: from localhost (10.203.177.66) by frapeml500008.china.huawei.com (7.182.85.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Fri, 8 Aug 2025 12:44:43 +0200 Date: Fri, 8 Aug 2025 11:44:42 +0100 To: Markus Armbruster CC: , , Subject: Re: [PATCH 03/12] hw/cxl: Convert cxl_fmws_link() to Error Message-ID: <20250808114442.0000234d@huawei.com> In-Reply-To: <20250808080823.2638861-4-armbru@redhat.com> References: <20250808080823.2638861-1-armbru@redhat.com> <20250808080823.2638861-4-armbru@redhat.com> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.42; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.203.177.66] X-ClientProxiedBy: lhrpeml500002.china.huawei.com (7.191.160.78) To frapeml500008.china.huawei.com (7.182.85.71) X-Host-Lookup-Failed: Reverse DNS lookup failed for 185.176.79.56 (deferred) Received-SPF: pass client-ip=185.176.79.56; envelope-from=jonathan.cameron@huawei.com; helo=frasgout.his.huawei.com X-Spam_score_int: -33 X-Spam_score: -3.4 X-Spam_bar: --- X-Spam_report: (-3.4 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-to: Jonathan Cameron From: Jonathan Cameron via Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Fri, 8 Aug 2025 10:08:14 +0200 Markus Armbruster wrote: > Functions that use an Error **errp parameter to return errors should > not also report them to the user, because reporting is the caller's > job. When the caller does, the error is reported twice. When it > doesn't (because it recovered from the error), there is no error to > report, i.e. the report is bogus. > > cxl_fmws_link_targets() violates this principle: it calls > error_setg(&error_fatal, ...) via cxl_fmws_link(). Goes back to > commit 584f722eb3ab (hw/cxl: Make the CXL fixed memory windows > devices.) Currently harmless, because cxl_fmws_link_targets()'s > callers always pass &error_fatal. Clean this up by converting > cxl_fmws_link() to Error. Patch is definitely an improvement though I'm no sure how it is really a violation of the above principle given it has no effect on being called twice for example. > > Cc: Jonathan Cameron > Signed-off-by: Markus Armbruster The -1 return is perhaps unrelated to the main thing here, but does make more sense than return 1 so fair enough. None of the above comments I've raised are that important to me though. Reviewed-by: Jonathan Cameron > --- > hw/cxl/cxl-host.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/hw/cxl/cxl-host.c b/hw/cxl/cxl-host.c > index 5c2ce25a19..0d891c651d 100644 > --- a/hw/cxl/cxl-host.c > +++ b/hw/cxl/cxl-host.c > @@ -72,6 +72,7 @@ static void cxl_fixed_memory_window_config(CXLFixedMemoryWindowOptions *object, > > static int cxl_fmws_link(Object *obj, void *opaque) > { > + Error **errp = opaque; > struct CXLFixedWindow *fw; > int i; > > @@ -87,9 +88,9 @@ static int cxl_fmws_link(Object *obj, void *opaque) > o = object_resolve_path_type(fw->targets[i], TYPE_PXB_CXL_DEV, > &ambig); > if (!o) { > - error_setg(&error_fatal, "Could not resolve CXLFM target %s", > + error_setg(errp, "Could not resolve CXLFM target %s", > fw->targets[i]); > - return 1; > + return -1; > } > fw->target_hbs[i] = PXB_CXL_DEV(o); > } > @@ -99,7 +100,7 @@ static int cxl_fmws_link(Object *obj, void *opaque) > void cxl_fmws_link_targets(Error **errp) > { > /* Order doesn't matter for this, so no need to build list */ > - object_child_foreach_recursive(object_get_root(), cxl_fmws_link, NULL); > + object_child_foreach_recursive(object_get_root(), cxl_fmws_link, errp); > } > > static bool cxl_hdm_find_target(uint32_t *cache_mem, hwaddr addr,