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From: Christoph Hellwig <hch@infradead.org>
To: Nirmal Patel <nirmal.patel@linux.intel.com>
Cc: linux-pci@vger.kernel.org, paul.m.stillwell.jr@intel.com,
	Jim Harris <james.r.harris@intel.com>
Subject: Re: [PATCH] PCI: fixup PCI_INTERRUPT_LINE for VMD downstream devices
Date: Wed, 24 Jul 2024 11:36:31 -0700	[thread overview]
Message-ID: <ZqFJr7Y3Vemjv2SC@infradead.org> (raw)
In-Reply-To: <20240724170040.5193-1-nirmal.patel@linux.intel.com>

On Wed, Jul 24, 2024 at 10:00:40AM -0700, Nirmal Patel wrote:
> +#if IS_ENABLED(CONFIG_VMD)
> +/* 
> + * VMD does not support legacy interrupts for downstream devices.
> + * So PCI_INTERRPUT_LINE needs to be initialized to 0 to ensure OS
> + * doesn't try to configure a legacy irq.
> + */

The wording is a bit weird, Linux is the OS normally.  Or is this
about guest OSes in virtualized environments?  Given how VMD bypasses
a lot of boundaries can we even assign individual devices to VFIO?
And if so is that actually safe or should we prohibit it?


  reply	other threads:[~2024-07-24 18:36 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-07-24 17:00 [PATCH] PCI: fixup PCI_INTERRUPT_LINE for VMD downstream devices Nirmal Patel
2024-07-24 18:36 ` Christoph Hellwig [this message]
2024-07-31 19:21   ` Nirmal Patel
2024-07-24 19:10 ` Bjorn Helgaas
2024-07-25  4:10   ` Manivannan Sadhasivam
2024-07-25 21:22     ` Nirmal Patel
2024-07-29 20:08     ` Nirmal Patel
2024-07-30  5:28       ` Manivannan Sadhasivam
2024-07-30 17:51         ` Nirmal Patel
2024-07-31  3:07           ` Manivannan Sadhasivam
2024-08-01 18:57             ` Nirmal Patel
2024-07-29 20:10   ` Nirmal Patel

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