From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from list by lists.gnu.org with archive (Exim 4.90_1) id 1icrLu-0007kL-7Y for mharc-qemu-riscv@gnu.org; Thu, 05 Dec 2019 08:39:32 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:48787) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1icrLh-0007hz-Tr for qemu-riscv@nongnu.org; Thu, 05 Dec 2019 08:39:20 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1icrLg-0004Sr-DN for qemu-riscv@nongnu.org; Thu, 05 Dec 2019 08:39:17 -0500 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:29080 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1icrLd-0004Pr-4J for qemu-riscv@nongnu.org; Thu, 05 Dec 2019 08:39:13 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1575553150; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=hnhb/x6YaZwfbYwlyRlda7171y0HPcU5qK2g5bnRUHs=; b=HV66kXuStetuAOJKDAWC5J25aq+52xIA7o9LJKwmjZYRVw6H80MmvmIgnBqPueQZ/u6qFZ z/0cXKIZFJBuTmnvKCAqULunXONc6vmcpbVxpy5mGnh/8G0NsAeL2klQXKcSe8cC3rJyA8 mY/KRgMIkamjdIu4Qgj/o3A/P22H8H0= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-103-In8rOFh3PGWTvk4no7Xklw-1; Thu, 05 Dec 2019 07:37:20 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 247F5100; Thu, 5 Dec 2019 12:37:14 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-116-134.ams2.redhat.com [10.36.116.134]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 59B435C1B5; Thu, 5 Dec 2019 12:36:42 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id BB0531138606; Thu, 5 Dec 2019 13:36:40 +0100 (CET) From: Markus Armbruster To: Vladimir Sementsov-Ogievskiy Cc: Markus Armbruster , Ronnie Sahlberg , Jeff Cody , Jan Kiszka , Alberto Garcia , Hailiang Zhang , "qemu-block\@nongnu.org" , Aleksandar Rikalo , Halil Pasic , =?utf-8?Q?Herv=C3=A9?= Poussineau , Anthony Perard , Samuel Thibault , Laszlo Ersek , Jason Wang , Laurent Vivier , Eduardo Habkost , Xie Changlong , Peter Lieven , "Dr. David Alan Gilbert" , Beniamino Galvani , Eric Auger , Alex Williamson , Stefan Hajnoczi , John Snow , Richard Henderson , Kevin Wolf , Andrew Jeffery , Chris Wulff , Subbaraya Sundeep , Michael Walle , "qemu-ppc\@nongnu.org" , Bastian Koppelmann , Igor Mammedov , Fam Zheng , Peter Maydell , "sheepdog\@lists.wpkg.org" , Matthew Rosato , David Hildenbrand , Palmer Dabbelt , Eric Farman , Max Filippov , Hannes Reinecke , Stefano Stabellini , "Gonglei \(Arei\)" , Liu Yuan , Artyom Tarasenko , Thomas Huth , Amit Shah , Stefan Weil , Greg Kurz , Yuval Shaia , "qemu-s390x\@nongnu.org" , "qemu-arm\@nongnu.org" , Peter Chubb , =?utf-8?Q?C=C3=A9dric?= Le Goater , Stafford Horne , "qemu-riscv\@nongnu.org" , Cornelia Huck , Aleksandar Markovic , Aurelien Jarno , Paul Burton , Sagar Karandikar , Paul Durrant , Anthony Green , Gerd Hoffmann , "Edgar E. Iglesias" , Guan Xuetao , Ari Sundholm , Juan Quintela , Michael Roth , Christian Borntraeger , Joel Stanley , Jason Dillaman , Antony Pavlov , "xen-devel\@lists.xenproject.org" , "integration\@gluster.org" , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , "Richard W.M. Jones" , Andrew Baumann , Max Reitz , Denis Lunev , "Michael S. Tsirkin" , Mark Cave-Ayland , "qemu-devel\@nongnu.org" , Vincenzo Maffione , Marek Vasut , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Alistair Francis , Pavel Dovgalyuk , Giuseppe Lettieri , Luigi Rizzo , David Gibson , Tony Krowiak , Daniel P. =?utf-8?Q?Berrang=C3=A9?= , Xiao Guangrong , Pierre Morel , Wen Congyang , Jean-Christophe Dubois , Paolo Bonzini , Stefan Berger Subject: Re: [RFC v5 024/126] error: auto propagated local_err References: <20191011160552.22907-1-vsementsov@virtuozzo.com> <20191011160552.22907-25-vsementsov@virtuozzo.com> <87muc8p24w.fsf@dusky.pond.sub.org> <55393c08-5bda-8042-1a95-f350b3781d99@virtuozzo.com> Date: Thu, 05 Dec 2019 13:36:40 +0100 In-Reply-To: <55393c08-5bda-8042-1a95-f350b3781d99@virtuozzo.com> (Vladimir Sementsov-Ogievskiy's message of "Thu, 5 Dec 2019 09:38:49 +0000") Message-ID: <87d0d3c5k7.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-MC-Unique: In8rOFh3PGWTvk4no7Xklw-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 205.139.110.61 X-BeenThere: qemu-riscv@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 05 Dec 2019 13:39:22 -0000 Vladimir Sementsov-Ogievskiy writes: > 04.12.2019 17:59, Markus Armbruster wrote: >> Vladimir Sementsov-Ogievskiy writes: >>=20 >>> Here is introduced ERRP_AUTO_PROPAGATE macro, to be used at start of >>> functions with errp OUT parameter. >>> >>> It has three goals: >>> >>> 1. Fix issue with error_fatal & error_prepend/error_append_hint: user >>> can't see this additional information, because exit() happens in >>> error_setg earlier than information is added. [Reported by Greg Kurz] >>> >>> 2. Fix issue with error_abort & error_propagate: when we wrap >>> error_abort by local_err+error_propagate, resulting coredump will >>> refer to error_propagate and not to the place where error happened. >>=20 >> I get what you mean, but I have plenty of context. >>=20 >>> (the macro itself doesn't fix the issue, but it allows to [3.] drop all >>> local_err+error_propagate pattern, which will definitely fix the issue) >>=20 >> The parenthesis is not part of the goal. >>=20 >>> [Reported by Kevin Wolf] >>> >>> 3. Drop local_err+error_propagate pattern, which is used to workaround >>> void functions with errp parameter, when caller wants to know resulting >>> status. (Note: actually these functions could be merely updated to >>> return int error code). >>> >>> To achieve these goals, we need to add invocation of the macro at start >>> of functions, which needs error_prepend/error_append_hint (1.); add >>> invocation of the macro at start of functions which do >>> local_err+error_propagate scenario the check errors, drop local errors >>> from them and just use *errp instead (2., 3.). >>=20 >> The paragraph talks about two cases: 1. and 2.+3.=20 > > Hmm, I don't think so.. 1. and 2. are issues. 3. is a refactoring.. We ju= st > fix achieve 2 and 3 by one action. > >> Makes me think we >> want two paragraphs, each illustrated with an example. >>=20 >> What about you provide the examples, and then I try to polish the prose? > > 1: error_fatal problem > > Assume the following code flow: > > int f1(errp) { > ... > ret =3D f2(errp); > if (ret < 0) { > error_append_hint(errp, "very useful hint"); > return ret; > } > ... > } > > Now, if we call f1 with &error_fatal argument and f2 fails, the program > will exit immediately inside f2, when setting the errp. User will not > see the hint. > > So, in this case we should use local_err. How does this example look after the transformation? > 2: error_abort problem > > Now, consider functions without return value. We normally use local_err > variable to catch failures: > > void f1(errp) { > Error *local_err =3D NULL; > ... > f2(&local_err); > if (local_err) { > error_propagate(errp, local_err); > return; > } > ... > } > > Now, if we call f2 with &error_abort and f2 fails, the stack in resulting > crash dump will point to error_propagate, not to the failure point in f2, > which complicates debugging. > > So, we should never wrap error_abort by local_err. Likewise. > > =3D=3D=3D > > Our solution: > > - Fixes [1.], adding invocation of new macro into functions with error_ap= pen_hint/error_prepend, > New macro will wrap error_fatal. > - Fixes [2.], by switching from hand-written local_err to smart macro, wh= ich never > wraps error_abort. > - Handles [3.], by switching to macro, which is less code > - Additionally, macro doesn't wrap normal non-zero errp, to avoid extra p= ropagations > (in fact, error_propagate is called, but returns immediately on first = if (!local_err)) From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by 2002:a19:c345:0:0:0:0:0 with SMTP id t66csp2056705lff; Thu, 5 Dec 2019 05:54:24 -0800 (PST) X-Google-Smtp-Source: APXvYqx0YVa5INUy3fn/TP1C46NM2BdErq+yDO+aV6z4f8WZB/x63s9/X344w5qs1KPfr2xHxx4N X-Received: by 2002:a05:6808:12:: with SMTP id u18mr1417744oic.51.1575554064487; Thu, 05 Dec 2019 05:54:24 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1575554064; cv=none; d=google.com; s=arc-20160816; b=juUSJJbqnlZMhe8npUcx0XVtvAA4BOVWHUrVB0wH2BHrXcUKLRsc+FMMUYG1W1FJxd wofGBdyQoQnVz1Q92tIA5yi3TpFjBBzMtSbcxyTUSBfaaDMMy5XcsRSxgK5cOsMv15N1 MhahXJesI8PRDxTPFF1WMiwvburc+KtUCwGy2P8HdLveqj2+D4aQstLC1gqO05E4WG9+ r/SABTBX9Cgpu0fkagtDePn3UEitzezO/m2mtH65bJCiKYfjzqfWKfRDLlK+gDNWTN8g 73i/h/B8Qr45LL9apSLWOwVwVywfeShUsp1/6ecnQJvjNE+zMR684RYNYIry3juO+rZ/ l0ig== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:errors-to:cc:list-subscribe:list-help:list-post:list-archive :list-unsubscribe:list-id:precedence:content-transfer-encoding :mime-version:user-agent:message-id:in-reply-to:date:references :subject:to:from:dkim-signature; bh=hnhb/x6YaZwfbYwlyRlda7171y0HPcU5qK2g5bnRUHs=; b=EJvQDzGhaCmNSz8kb1fDJHF5aapUymy++muhpmSTXxmEzu3JEFua/1F0aUWPvfUVoB 1pmygSNigzX1s561NpueOH+x+X40JSV9BbgqLH8evXgfhcXP4JEdzlPnvDWmLb88Y7BS f2QbjnJ9zjSp4eVncpNqBK5yc5addUTwzxBov6pqqtskUmKCsPk6fgdD4bGflyOyNB/Z tc1soBJ5pJ3TPlQLTy/t3vW6zYmyuylswOiduX485ezQ5Bvn+5ux+CC//9fRaQhk89Gw huArEnpSf8pKqAKneBy9Imm+U1rOI+Cq7eWD6N+o0ywzkBBt4u/Zaik4+VydjfiZGgvr LuCw== ARC-Authentication-Results: i=1; mx.google.com; dkim=fail header.i=@redhat.com header.s=mimecast20190719 header.b=HV66kXuS; spf=pass (google.com: domain of qemu-devel-bounces+alex.bennee=linaro.org@nongnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom="qemu-devel-bounces+alex.bennee=linaro.org@nongnu.org"; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org. 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Thu, 05 Dec 2019 07:37:20 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 247F5100; Thu, 5 Dec 2019 12:37:14 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-116-134.ams2.redhat.com [10.36.116.134]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 59B435C1B5; Thu, 5 Dec 2019 12:36:42 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id BB0531138606; Thu, 5 Dec 2019 13:36:40 +0100 (CET) From: Markus Armbruster To: Vladimir Sementsov-Ogievskiy Subject: Re: [RFC v5 024/126] error: auto propagated local_err References: <20191011160552.22907-1-vsementsov@virtuozzo.com> <20191011160552.22907-25-vsementsov@virtuozzo.com> <87muc8p24w.fsf@dusky.pond.sub.org> <55393c08-5bda-8042-1a95-f350b3781d99@virtuozzo.com> Date: Thu, 05 Dec 2019 13:36:40 +0100 In-Reply-To: <55393c08-5bda-8042-1a95-f350b3781d99@virtuozzo.com> (Vladimir Sementsov-Ogievskiy's message of "Thu, 5 Dec 2019 09:38:49 +0000") Message-ID: <87d0d3c5k7.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-MC-Unique: In8rOFh3PGWTvk4no7Xklw-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 205.139.110.61 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Ronnie Sahlberg , Jeff Cody , Jan Kiszka , Alberto Garcia , Hailiang Zhang , "qemu-block@nongnu.org" , Aleksandar Rikalo , Halil Pasic , =?utf-8?Q?Herv=C3=A9?= Poussineau , Anthony Perard , Samuel Thibault , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Anthony Green , Laurent Vivier , Eduardo Habkost , Xie Changlong , Peter Lieven , "Dr. David Alan Gilbert" , Beniamino Galvani , Eric Auger , Alex Williamson , Stefan Hajnoczi , John Snow , Richard Henderson , Kevin Wolf , Andrew Jeffery , Chris Wulff , Subbaraya Sundeep , Michael Walle , "qemu-ppc@nongnu.org" , Bastian Koppelmann , Igor Mammedov , Fam Zheng , Peter Maydell , "sheepdog@lists.wpkg.org" , Matthew Rosato , David Hildenbrand , Palmer Dabbelt , Eric Farman , Max Filippov , Hannes Reinecke , Stefano Stabellini , "Gonglei \(Arei\)" , Liu Yuan , Artyom Tarasenko , Thomas Huth , Amit Shah , Stefan Weil , Greg Kurz , Yuval Shaia , "qemu-s390x@nongnu.org" , "qemu-arm@nongnu.org" , Peter Chubb , =?utf-8?Q?C=C3=A9dric?= Le Goater , Stafford Horne , "qemu-riscv@nongnu.org" , Cornelia Huck , Aleksandar Markovic , Aurelien Jarno , Paul Burton , Sagar Karandikar , Paul Durrant , Jason Wang , Gerd Hoffmann , "Edgar E. Iglesias" , Guan Xuetao , Ari Sundholm , Juan Quintela , Michael Roth , Christian Borntraeger , Joel Stanley , Jason Dillaman , Antony Pavlov , "xen-devel@lists.xenproject.org" , "integration@gluster.org" , Laszlo Ersek , "Richard W.M. Jones" , Andrew Baumann , Max Reitz , Denis Lunev , "Michael S. Tsirkin" , Mark Cave-Ayland , "qemu-devel@nongnu.org" , Vincenzo Maffione , Marek Vasut , Markus Armbruster , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Alistair Francis , Pavel Dovgalyuk , Giuseppe Lettieri , Luigi Rizzo , David Gibson , Tony Krowiak , "Daniel P. =?utf-8?Q?Berrang=C3=A9?=" , Xiao Guangrong , Pierre Morel , Wen Congyang , Jean-Christophe Dubois , Paolo Bonzini , Stefan Berger Errors-To: qemu-devel-bounces+alex.bennee=linaro.org@nongnu.org Sender: "Qemu-devel" X-TUID: 2DGfO2+1+Ft0 Vladimir Sementsov-Ogievskiy writes: > 04.12.2019 17:59, Markus Armbruster wrote: >> Vladimir Sementsov-Ogievskiy writes: >>=20 >>> Here is introduced ERRP_AUTO_PROPAGATE macro, to be used at start of >>> functions with errp OUT parameter. >>> >>> It has three goals: >>> >>> 1. Fix issue with error_fatal & error_prepend/error_append_hint: user >>> can't see this additional information, because exit() happens in >>> error_setg earlier than information is added. [Reported by Greg Kurz] >>> >>> 2. Fix issue with error_abort & error_propagate: when we wrap >>> error_abort by local_err+error_propagate, resulting coredump will >>> refer to error_propagate and not to the place where error happened. >>=20 >> I get what you mean, but I have plenty of context. >>=20 >>> (the macro itself doesn't fix the issue, but it allows to [3.] drop all >>> local_err+error_propagate pattern, which will definitely fix the issue) >>=20 >> The parenthesis is not part of the goal. >>=20 >>> [Reported by Kevin Wolf] >>> >>> 3. Drop local_err+error_propagate pattern, which is used to workaround >>> void functions with errp parameter, when caller wants to know resulting >>> status. (Note: actually these functions could be merely updated to >>> return int error code). >>> >>> To achieve these goals, we need to add invocation of the macro at start >>> of functions, which needs error_prepend/error_append_hint (1.); add >>> invocation of the macro at start of functions which do >>> local_err+error_propagate scenario the check errors, drop local errors >>> from them and just use *errp instead (2., 3.). >>=20 >> The paragraph talks about two cases: 1. and 2.+3.=20 > > Hmm, I don't think so.. 1. and 2. are issues. 3. is a refactoring.. We ju= st > fix achieve 2 and 3 by one action. > >> Makes me think we >> want two paragraphs, each illustrated with an example. >>=20 >> What about you provide the examples, and then I try to polish the prose? > > 1: error_fatal problem > > Assume the following code flow: > > int f1(errp) { > ... > ret =3D f2(errp); > if (ret < 0) { > error_append_hint(errp, "very useful hint"); > return ret; > } > ... > } > > Now, if we call f1 with &error_fatal argument and f2 fails, the program > will exit immediately inside f2, when setting the errp. User will not > see the hint. > > So, in this case we should use local_err. How does this example look after the transformation? > 2: error_abort problem > > Now, consider functions without return value. We normally use local_err > variable to catch failures: > > void f1(errp) { > Error *local_err =3D NULL; > ... > f2(&local_err); > if (local_err) { > error_propagate(errp, local_err); > return; > } > ... > } > > Now, if we call f2 with &error_abort and f2 fails, the stack in resulting > crash dump will point to error_propagate, not to the failure point in f2, > which complicates debugging. > > So, we should never wrap error_abort by local_err. Likewise. > > =3D=3D=3D > > Our solution: > > - Fixes [1.], adding invocation of new macro into functions with error_ap= pen_hint/error_prepend, > New macro will wrap error_fatal. > - Fixes [2.], by switching from hand-written local_err to smart macro, wh= ich never > wraps error_abort. > - Handles [3.], by switching to macro, which is less code > - Additionally, macro doesn't wrap normal non-zero errp, to avoid extra p= ropagations > (in fact, error_propagate is called, but returns immediately on first = if (!local_err)) 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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 0D232C43603 for ; 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Thu, 05 Dec 2019 07:36:53 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0980B184CAD3; Thu, 5 Dec 2019 12:36:45 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-116-134.ams2.redhat.com [10.36.116.134]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 626435E24A; Thu, 5 Dec 2019 12:36:42 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id BB0531138606; Thu, 5 Dec 2019 13:36:40 +0100 (CET) From: Markus Armbruster To: Vladimir Sementsov-Ogievskiy References: <20191011160552.22907-1-vsementsov@virtuozzo.com> <20191011160552.22907-25-vsementsov@virtuozzo.com> <87muc8p24w.fsf@dusky.pond.sub.org> <55393c08-5bda-8042-1a95-f350b3781d99@virtuozzo.com> Date: Thu, 05 Dec 2019 13:36:40 +0100 In-Reply-To: <55393c08-5bda-8042-1a95-f350b3781d99@virtuozzo.com> (Vladimir Sementsov-Ogievskiy's message of "Thu, 5 Dec 2019 09:38:49 +0000") Message-ID: <87d0d3c5k7.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-MC-Unique: YHjN-YtaNgqYAg5tVDJ8nA-1 X-Mimecast-Spam-Score: 0 X-Mailman-Approved-At: Fri, 06 Dec 2019 05:53:37 +0000 Subject: Re: [Xen-devel] [RFC v5 024/126] error: auto propagated local_err X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Ronnie Sahlberg , Jeff Cody , Jan Kiszka , Alberto Garcia , Hailiang Zhang , "qemu-block@nongnu.org" , Aleksandar Rikalo , Halil Pasic , =?utf-8?Q?Herv=C3=A9?= Poussineau , Anthony Perard , Samuel Thibault , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Anthony Green , Laurent Vivier , Eduardo Habkost , Xie Changlong , Peter Lieven , "Dr. David Alan Gilbert" , Beniamino Galvani , Eric Auger , Alex Williamson , Stefan Hajnoczi , John Snow , Richard Henderson , Kevin Wolf , Andrew Jeffery , Chris Wulff , Subbaraya Sundeep , Michael Walle , "qemu-ppc@nongnu.org" , Bastian Koppelmann , Igor Mammedov , Fam Zheng , Peter Maydell , "sheepdog@lists.wpkg.org" , Matthew Rosato , David Hildenbrand , Palmer Dabbelt , Eric Farman , Max Filippov , Hannes Reinecke , Stefano Stabellini , "Gonglei \(Arei\)" , Liu Yuan , Artyom Tarasenko , Thomas Huth , Amit Shah , Stefan Weil , Greg Kurz , Yuval Shaia , "qemu-s390x@nongnu.org" , "qemu-arm@nongnu.org" , Peter Chubb , =?utf-8?Q?C=C3=A9dric?= Le Goater , Stafford Horne , "qemu-riscv@nongnu.org" , Cornelia Huck , Aleksandar Markovic , Aurelien Jarno , Paul Burton , Sagar Karandikar , Paul Durrant , Jason Wang , Gerd Hoffmann , "Edgar E. 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Tsirkin" , Mark Cave-Ayland , "qemu-devel@nongnu.org" , Vincenzo Maffione , Marek Vasut , Markus Armbruster , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Alistair Francis , Pavel Dovgalyuk , Giuseppe Lettieri , Luigi Rizzo , David Gibson , Tony Krowiak , "Daniel P. =?utf-8?Q?Berrang=C3=A9?=" , Xiao Guangrong , Pierre Morel , Wen Congyang , Jean-Christophe Dubois , Paolo Bonzini , Stefan Berger Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" VmxhZGltaXIgU2VtZW50c292LU9naWV2c2tpeSA8dnNlbWVudHNvdkB2aXJ0dW96em8uY29tPiB3 cml0ZXM6Cgo+IDA0LjEyLjIwMTkgMTc6NTksIE1hcmt1cyBBcm1icnVzdGVyIHdyb3RlOgo+PiBW bGFkaW1pciBTZW1lbnRzb3YtT2dpZXZza2l5IDx2c2VtZW50c292QHZpcnR1b3p6by5jb20+IHdy aXRlczoKPj4gCj4+PiBIZXJlIGlzIGludHJvZHVjZWQgRVJSUF9BVVRPX1BST1BBR0FURSBtYWNy bywgdG8gYmUgdXNlZCBhdCBzdGFydCBvZgo+Pj4gZnVuY3Rpb25zIHdpdGggZXJycCBPVVQgcGFy YW1ldGVyLgo+Pj4KPj4+IEl0IGhhcyB0aHJlZSBnb2FsczoKPj4+Cj4+PiAxLiBGaXggaXNzdWUg 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