From patchwork Fri Jul 20 00:45:28 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 946679 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; 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 Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 41WsdS23Hyz9s5c for ; Fri, 20 Jul 2018 10:46:18 +1000 (AEST) Received: from localhost ([::1]:45918 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fgJYk-0007Qb-KM for incoming@patchwork.ozlabs.org; Thu, 19 Jul 2018 20:46:14 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33428) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fgJYA-0007Q1-KK for qemu-devel@nongnu.org; Thu, 19 Jul 2018 20:45:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fgJY9-0003dt-LT for qemu-devel@nongnu.org; Thu, 19 Jul 2018 20:45:38 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:43986 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fgJY9-0003dh-F2 for qemu-devel@nongnu.org; Thu, 19 Jul 2018 20:45:37 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 034F240778BB; Fri, 20 Jul 2018 00:45:37 +0000 (UTC) Received: from jason-ThinkPad-T450s.redhat.com (ovpn-12-42.pek2.redhat.com [10.72.12.42]) by smtp.corp.redhat.com (Postfix) with ESMTP id CFDB6111E40B; Fri, 20 Jul 2018 00:45:34 +0000 (UTC) From: Jason Wang To: peter.maydell@linaro.org, qemu-devel@nongnu.org Date: Fri, 20 Jul 2018 08:45:28 +0800 Message-Id: <1532047529-17961-2-git-send-email-jasowang@redhat.com> In-Reply-To: <1532047529-17961-1-git-send-email-jasowang@redhat.com> References: <1532047529-17961-1-git-send-email-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Fri, 20 Jul 2018 00:45:37 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Fri, 20 Jul 2018 00:45:37 +0000 (UTC) for IP:'10.11.54.3' DOMAIN:'int-mx03.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jasowang@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PULL 1/2] e1000e: Prevent MSI/MSI-X storms X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jan Kiszka , Jason Wang Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Jan Kiszka Only signal MSI/MSI-X events on rising edges. So far we re-triggered the interrupt sources even if the guest did no consumed the pending one, easily causing interrupt storms. Issue was observable with Linux 4.16 e1000e driver when MSI-X was used. Vector 2 was causing interrupt storms after the driver activated the device. Signed-off-by: Jan Kiszka Signed-off-by: Jason Wang --- hw/net/e1000e_core.c | 11 +++++++++++ hw/net/e1000e_core.h | 2 ++ 2 files changed, 13 insertions(+) diff --git a/hw/net/e1000e_core.c b/hw/net/e1000e_core.c index 9504891..2a221c2 100644 --- a/hw/net/e1000e_core.c +++ b/hw/net/e1000e_core.c @@ -2023,6 +2023,7 @@ e1000e_msix_notify_one(E1000ECore *core, uint32_t cause, uint32_t int_cfg) effective_eiac = core->mac[EIAC] & cause; core->mac[ICR] &= ~effective_eiac; + core->msi_causes_pending &= ~effective_eiac; if (!(core->mac[CTRL_EXT] & E1000_CTRL_EXT_IAME)) { core->mac[IMS] &= ~effective_eiac; @@ -2119,6 +2120,13 @@ e1000e_send_msi(E1000ECore *core, bool msix) { uint32_t causes = core->mac[ICR] & core->mac[IMS] & ~E1000_ICR_ASSERTED; + core->msi_causes_pending &= causes; + causes ^= core->msi_causes_pending; + if (causes == 0) { + return; + } + core->msi_causes_pending |= causes; + if (msix) { e1000e_msix_notify(core, causes); } else { @@ -2156,6 +2164,9 @@ e1000e_update_interrupt_state(E1000ECore *core) core->mac[ICS] = core->mac[ICR]; interrupts_pending = (core->mac[IMS] & core->mac[ICR]) ? true : false; + if (!interrupts_pending) { + core->msi_causes_pending = 0; + } trace_e1000e_irq_pending_interrupts(core->mac[ICR] & core->mac[IMS], core->mac[ICR], core->mac[IMS]); diff --git a/hw/net/e1000e_core.h b/hw/net/e1000e_core.h index 7d8ff41..63a1551 100644 --- a/hw/net/e1000e_core.h +++ b/hw/net/e1000e_core.h @@ -109,6 +109,8 @@ struct E1000Core { NICState *owner_nic; PCIDevice *owner; void (*owner_start_recv)(PCIDevice *d); + + uint32_t msi_causes_pending; }; void