From patchwork Fri Jun 5 09:47:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 1304017 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=P3HLDNNp; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 49ddBy5zVtz9sPF for ; Fri, 5 Jun 2020 19:48:58 +1000 (AEST) Received: from localhost ([::1]:53940 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jh8y8-0001u3-93 for incoming@patchwork.ozlabs.org; Fri, 05 Jun 2020 05:48:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:41462) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jh8xX-0001rz-Hk for qemu-devel@nongnu.org; Fri, 05 Jun 2020 05:48:19 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:44890 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jh8xW-0006is-OA for qemu-devel@nongnu.org; Fri, 05 Jun 2020 05:48:19 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591350497; 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=0KR6x6asC/HYUxAOydHgzfA0NWWwl9rylofm3HE79GE=; b=P3HLDNNpa0qp7Z36dPbJNV81Jry9Qt1aCsfRn78Vl+ymQLziSmRCOxq5cPbLMVwWFMEi7i +mlCQYCTgSRWd1GwUpaGqNzWl9htd+3LE4CDD+w5TauKTCfCp1aUq/an4LWIihDASZjubv 2N1w1N7h1Y3oXYMiEYkB9+WgMNWSKEs= 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-173-sLx1jlAlOB--0T_DW9qpiw-1; Fri, 05 Jun 2020 05:48:14 -0400 X-MC-Unique: sLx1jlAlOB--0T_DW9qpiw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id CD0BA107ACCA; Fri, 5 Jun 2020 09:48:12 +0000 (UTC) Received: from localhost (ovpn-114-214.ams2.redhat.com [10.36.114.214]) by smtp.corp.redhat.com (Postfix) with ESMTP id 97E236606D; Fri, 5 Jun 2020 09:48:02 +0000 (UTC) From: Stefan Hajnoczi To: Peter Maydell , qemu-devel@nongnu.org Subject: [PULL 01/11] io_uring: retry io_uring_submit() if it fails with errno=EINTR Date: Fri, 5 Jun 2020 10:47:40 +0100 Message-Id: <20200605094750.149957-2-stefanha@redhat.com> In-Reply-To: <20200605094750.149957-1-stefanha@redhat.com> References: <20200605094750.149957-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.120; envelope-from=stefanha@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/05 03:07:04 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -3 X-Spam_score: -0.4 X-Spam_bar: / X-Spam_report: (-0.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, MIME_BASE64_TEXT=1.741, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN X-Spam_action: no action 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: Fam Zheng , Kevin Wolf , Thomas Huth , qemu-block@nongnu.org, Laurent Vivier , Julia Suvorova , Max Reitz , Alexander Bulekov , Bandan Das , qemu-arm@nongnu.org, Stefan Hajnoczi , Keith Busch , Paolo Bonzini , Stefano Garzarella , Aarushi Mehta , Richard Henderson Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Stefano Garzarella As recently documented [1], io_uring_enter(2) syscall can return an error (errno=EINTR) if the operation was interrupted by a delivery of a signal before it could complete. This should happen when IORING_ENTER_GETEVENTS flag is used, for example during io_uring_submit_and_wait() or during io_uring_submit() when IORING_SETUP_IOPOLL is enabled. We shouldn't have this problem for now, but it's better to prevent it. [1] https://github.com/axboe/liburing/commit/344355ec6619de8f4e64584c9736530b5346e4f4 Signed-off-by: Stefano Garzarella Message-id: 20200519133041.112138-1-sgarzare@redhat.com Signed-off-by: Stefan Hajnoczi --- block/io_uring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/io_uring.c b/block/io_uring.c index a3142ca989..9765681f7c 100644 --- a/block/io_uring.c +++ b/block/io_uring.c @@ -231,7 +231,7 @@ static int ioq_submit(LuringState *s) trace_luring_io_uring_submit(s, ret); /* Prevent infinite loop if submission is refused */ if (ret <= 0) { - if (ret == -EAGAIN) { + if (ret == -EAGAIN || ret == -EINTR) { continue; } break;