Message-ID: <ee5db32f-c21e-287f-2a19-94c1ba6e8217@kaod.org>
Date:   Sat, 18 Dec 2021 21:25:40 +0100
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Subject: Re: [patch V3 28/35] PCI/MSI: Simplify pci_irq_get_affinity()
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To:     Thomas Gleixner <tglx@linutronix.de>,
        Nathan Chancellor <nathan@kernel.org>
CC:     LKML <linux-kernel@vger.kernel.org>,
        Bjorn Helgaas <helgaas@kernel.org>,
        Marc Zygnier <maz@kernel.org>,
        Alex Williamson <alex.williamson@redhat.com>,
        Kevin Tian <kevin.tian@intel.com>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Megha Dey <megha.dey@intel.com>,
        Ashok Raj <ashok.raj@intel.com>, <linux-pci@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Juergen Gross <jgross@suse.com>,
        <xen-devel@lists.xenproject.org>, Arnd Bergmann <arnd@arndb.de>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        <linuxppc-dev@lists.ozlabs.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Stuart Yoder <stuyoder@gmail.com>,
        Laurentiu Tudor <laurentiu.tudor@nxp.com>,
        Nishanth Menon <nm@ti.com>, Tero Kristo <kristo@kernel.org>,
        Santosh Shilimkar <ssantosh@kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        Vinod Koul <vkoul@kernel.org>, <dmaengine@vger.kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Joerg Roedel <joro@8bytes.org>,
        <iommu@lists.linux-foundation.org>,
        Jassi Brar <jassisinghbrar@gmail.com>,
        Peter Ujfalusi <peter.ujfalusi@gmail.com>,
        Sinan Kaya <okaya@kernel.org>
References: <20211210221642.869015045@linutronix.de>
 <20211210221814.900929381@linutronix.de> <Yb0PaCyo/6z3XOlf@archlinux-ax161>
 <87v8zm9pmd.ffs@tglx>
From:   =?UTF-8?Q?C=c3=a9dric_Le_Goater?= <clg@kaod.org>
In-Reply-To: <87v8zm9pmd.ffs@tglx>
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On 12/18/21 11:25, Thomas Gleixner wrote:
> On Fri, Dec 17 2021 at 15:30, Nathan Chancellor wrote:
>> On Fri, Dec 10, 2021 at 11:19:26PM +0100, Thomas Gleixner wrote:
>> I just bisected a boot failure on my AMD test desktop to this patch as
>> commit f48235900182 ("PCI/MSI: Simplify pci_irq_get_affinity()") in
>> -next. It looks like there is a problem with the NVMe drive after this
>> change according to the logs. Given that the hard drive is not getting
>> mounted for journald to write logs to, I am not really sure how to get
>> them from the machine so I have at least taken a picture of what I see
>> on my screen; open to ideas on that front!
> 
> Bah. Fix below.

That's a fix for the issue I was seeing on pseries with NVMe.

Tested-by: Cédric Le Goater <clg@kaod.org>

Thanks,

C.


> Thanks,
> 
>          tglx
> ---
> diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
> index 71802410e2ab..9b4910befeda 100644
> --- a/drivers/pci/msi/msi.c
> +++ b/drivers/pci/msi/msi.c
> @@ -1100,7 +1100,7 @@ EXPORT_SYMBOL(pci_irq_vector);
>    */
>   const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr)
>   {
> -	int irq = pci_irq_vector(dev, nr);
> +	int idx, irq = pci_irq_vector(dev, nr);
>   	struct msi_desc *desc;
>   
>   	if (WARN_ON_ONCE(irq <= 0))
> @@ -1113,7 +1113,10 @@ const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr)
>   
>   	if (WARN_ON_ONCE(!desc->affinity))
>   		return NULL;
> -	return &desc->affinity[nr].mask;
> +
> +	/* MSI has a mask array in the descriptor. */
> +	idx = dev->msi_enabled ? nr : 0;
> +	return &desc->affinity[idx].mask;
>   }
>   EXPORT_SYMBOL(pci_irq_get_affinity);
>   
>