From patchwork Wed Aug 26 11:17:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 11738185 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 859201751 for ; Wed, 26 Aug 2020 12:07:15 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 629B220838 for ; Wed, 26 Aug 2020 12:07:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="zIN8rRtD"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="ICrYp1XT" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 629B220838 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kAuCV-0002BS-K7; Wed, 26 Aug 2020 12:06:47 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kAu9I-000821-Ax for xen-devel@lists.xenproject.org; Wed, 26 Aug 2020 12:03:28 +0000 X-Inumbo-ID: cf71050b-2286-4bb3-8d71-ae7377f0f256 Received: from galois.linutronix.de (unknown [2a0a:51c0:0:12e:550::1]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id cf71050b-2286-4bb3-8d71-ae7377f0f256; Wed, 26 Aug 2020 12:01:49 +0000 (UTC) Message-Id: <20200826112334.889315931@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1598443308; 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: references:references; bh=cykkSf24RUQJOTwuG0VyPRnlzcI597ZZ2erY9w7Z858=; b=zIN8rRtDstwLjSbYqoe/Wc9kD7YWmQX95g6LuqqnKZeIXL7ixEiCyQPMyyYmpK7bLDOv6a CgkPN1a/yxGmVb6l7wya9/+xgLgs1ILCFlVdtx/TWRP1eJHmEdFFwWDl5XqTm9f0TPMfRZ tw8tcz3fZEbqTuhbOutbbgGiDfdG+gMiYSlxV0vFanbSDowqFpFS1LKNWSOOr43T6mHN2Y hpSKYgnX+YKs5f0emn4766Na/CrJdM4iI/cGUnqVztLRfOEpSQoYP0sA+DAKMe3ykn/i6E aNRDbWt9tyHlJrG8TMXJ3ambkrVnYLMrF+BJ+OMDFwOJ+K+PO3VbOMIlC6vvrg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1598443308; 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: references:references; bh=cykkSf24RUQJOTwuG0VyPRnlzcI597ZZ2erY9w7Z858=; b=ICrYp1XTC5U4lIY5xh2joAmFwqxVGQeU3Yoo/fhXIC7eLLf62NUoErEyKCXtf8lK82iEDf xbeyrCK376q7yiDg== Date: Wed, 26 Aug 2020 13:17:11 +0200 From: Thomas Gleixner To: LKML Cc: x86@kernel.org, Joerg Roedel , iommu@lists.linux-foundation.org, linux-hyperv@vger.kernel.org, Haiyang Zhang , Jon Derrick , Lu Baolu , Wei Liu , "K. Y. Srinivasan" , Stephen Hemminger , Steve Wahl , Dimitri Sivanich , Russ Anderson , linux-pci@vger.kernel.org, Bjorn Helgaas , Lorenzo Pieralisi , Konrad Rzeszutek Wilk , xen-devel@lists.xenproject.org, Juergen Gross , Boris Ostrovsky , Stefano Stabellini , Marc Zyngier , Greg Kroah-Hartman , "Rafael J. Wysocki" , Megha Dey , Jason Gunthorpe , Dave Jiang , Alex Williamson , Jacob Pan , Baolu Lu , Kevin Tian , Dan Williams Subject: [patch V2 43/46] genirq/msi: Provide and use msi_domain_set_default_info_flags() References: <20200826111628.794979401@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" MSI interrupts have some common flags which should be set not only for PCI/MSI interrupts. Move the PCI/MSI flag setting into a common function so it can be reused. Signed-off-by: Thomas Gleixner --- V2: New patch --- drivers/pci/msi.c | 7 +------ include/linux/msi.h | 1 + kernel/irq/msi.c | 24 ++++++++++++++++++++++++ 3 files changed, 26 insertions(+), 6 deletions(-) --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -1469,12 +1469,7 @@ struct irq_domain *pci_msi_create_irq_do if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS) pci_msi_domain_update_chip_ops(info); - info->flags |= MSI_FLAG_ACTIVATE_EARLY; - if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE)) - info->flags |= MSI_FLAG_MUST_REACTIVATE; - - /* PCI-MSI is oneshot-safe */ - info->chip->flags |= IRQCHIP_ONESHOT_SAFE; + msi_domain_set_default_info_flags(info); domain = msi_create_irq_domain(fwnode, info, parent); if (!domain) --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -410,6 +410,7 @@ int platform_msi_domain_alloc(struct irq void platform_msi_domain_free(struct irq_domain *domain, unsigned int virq, unsigned int nvec); void *platform_msi_get_host_data(struct irq_domain *domain); +void msi_domain_set_default_info_flags(struct msi_domain_info *info); #endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */ #ifdef CONFIG_PCI_MSI_IRQ_DOMAIN --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -70,6 +70,30 @@ void get_cached_msi_msg(unsigned int irq EXPORT_SYMBOL_GPL(get_cached_msi_msg); #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN +void msi_domain_set_default_info_flags(struct msi_domain_info *info) +{ + /* Required so that a device latches a valid MSI message on startup */ + info->flags |= MSI_FLAG_ACTIVATE_EARLY; + + /* + * Interrupt reservation mode allows to stear the MSI message of an + * inactive device to a special (usually spurious interrupt) target. + * This allows to prevent interrupt vector exhaustion e.g. on x86. + * But (PCI)MSI interrupts are activated early - see above - so the + * interrupt request/startup sequence would not try to allocate a + * usable vector which means that the device interupts would end + * up on the special vector and issue spurious interrupt messages. + * Setting the reactivation flag ensures that when the interrupt + * is requested the activation is invoked again so that a real + * vector can be allocated. + */ + if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE)) + info->flags |= MSI_FLAG_MUST_REACTIVATE; + + /* MSI is oneshot-safe at least in theory */ + info->chip->flags |= IRQCHIP_ONESHOT_SAFE; +} + static inline void irq_chip_write_msi_msg(struct irq_data *data, struct msi_msg *msg) {