From patchwork Mon Dec 6 22:27:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 12659873 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A986EC4167D for ; Mon, 6 Dec 2021 22:27:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356603AbhLFWbA (ORCPT ); Mon, 6 Dec 2021 17:31:00 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:45442 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242901AbhLFWa6 (ORCPT ); Mon, 6 Dec 2021 17:30:58 -0500 Message-ID: <20211206210223.929792157@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1638829647; 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: references:references; bh=wYOapsewmvCjRKNhvhV0vpzUO9z80CJEqQBEg5ZWMSo=; b=cLSzakHMaYNtI4aJ6BLkP0Y1ckKByNqQRdbeialjjHb7VsdJKr1LXNnGFwD5jPorL/dB3X r8LL7BBEXT9ttMDduYesmAWnKu89MMUh+WbP//3UR9Oqi8u6Ke9f0j6kvDzk55pgKJlLw8 pXM/pbZ+DKZAxpGnovR5d0BXBdradoJwITrMoZLhwgv5vAP0K0ZMzZys/cJmxk0kAoxLqB 9HeDnDnYxU3SNfvQbR+KwVpjQ6g9EPn1CLChmqViSe3oPCpxc2+ZyZ9945UmAuQkVFQb/B Ms+5OGgiP91cMgej9Fb+5+mTuU/pnBqgmKdO+oCNOau73VDp3kwOD/z+rrVPrQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1638829647; 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: references:references; bh=wYOapsewmvCjRKNhvhV0vpzUO9z80CJEqQBEg5ZWMSo=; b=AC1UyRei3djvmFCd8sCxirgN9BF19ZHUhoSg/ujiTsv7YGfDjxkFl5ncJxZvQt8R7ZWn4X QnYXgZVa/LFvUdBg== From: Thomas Gleixner To: LKML Cc: Bjorn Helgaas , Marc Zygnier , Alex Williamson , Kevin Tian , Jason Gunthorpe , Megha Dey , Ashok Raj , linux-pci@vger.kernel.org, Cedric Le Goater , Juergen Gross , Michael Ellerman , Paul Mackerras , Benjamin Herrenschmidt , linuxppc-dev@lists.ozlabs.org, Thomas Bogendoerfer , linux-mips@vger.kernel.org, Kalle Valo , Greg Kroah-Hartman , sparclinux@vger.kernel.org, x86@kernel.org, xen-devel@lists.xenproject.org, ath11k@lists.infradead.org, Wei Liu , linux-hyperv@vger.kernel.org, Christian Borntraeger , Heiko Carstens Subject: [patch V2 02/23] PCI/MSI: Fix pci_irq_vector()/pci_irq_get_affinity() References: <20211206210147.872865823@linutronix.de> MIME-Version: 1.0 Date: Mon, 6 Dec 2021 23:27:26 +0100 (CET) Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org pci_irq_vector() and pci_irq_get_affinity() use the list position to find the MSI-X descriptor at a given index. That's correct for the normal case where the entry number is the same as the list position. But it's wrong for cases where MSI-X was allocated with an entries array describing sparse entry numbers into the hardware message descriptor table. That's inconsistent at best. Make it always check the entry number because that's what the zero base index really means. This change won't break existing users which use a sparse entries array for allocation because these users retrieve the Linux interrupt number from the entries array after allocation and none of them uses pci_irq_vector() or pci_irq_get_affinity(). Fixes: aff171641d18 ("PCI: Provide sensible IRQ vector alloc/free routines") Signed-off-by: Thomas Gleixner Tested-by: Juergen Gross Reviewed-by: Jason Gunthorpe Acked-by: Bjorn Helgaas --- V2: Fix typo in subject - Jason --- drivers/pci/msi.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -1187,19 +1187,24 @@ EXPORT_SYMBOL(pci_free_irq_vectors); /** * pci_irq_vector - return Linux IRQ number of a device vector - * @dev: PCI device to operate on - * @nr: device-relative interrupt vector index (0-based). + * @dev: PCI device to operate on + * @nr: Interrupt vector index (0-based) + * + * @nr has the following meanings depending on the interrupt mode: + * MSI-X: The index in the MSI-X vector table + * MSI: The index of the enabled MSI vectors + * INTx: Must be 0 + * + * Return: The Linux interrupt number or -EINVAl if @nr is out of range. */ int pci_irq_vector(struct pci_dev *dev, unsigned int nr) { if (dev->msix_enabled) { struct msi_desc *entry; - int i = 0; for_each_pci_msi_entry(entry, dev) { - if (i == nr) + if (entry->msi_attrib.entry_nr == nr) return entry->irq; - i++; } WARN_ON_ONCE(1); return -EINVAL; @@ -1223,17 +1228,22 @@ EXPORT_SYMBOL(pci_irq_vector); * pci_irq_get_affinity - return the affinity of a particular MSI vector * @dev: PCI device to operate on * @nr: device-relative interrupt vector index (0-based). + * + * @nr has the following meanings depending on the interrupt mode: + * MSI-X: The index in the MSI-X vector table + * MSI: The index of the enabled MSI vectors + * INTx: Must be 0 + * + * Return: A cpumask pointer or NULL if @nr is out of range */ const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr) { if (dev->msix_enabled) { struct msi_desc *entry; - int i = 0; for_each_pci_msi_entry(entry, dev) { - if (i == nr) + if (entry->msi_attrib.entry_nr == nr) return &entry->affinity->mask; - i++; } WARN_ON_ONCE(1); return NULL;