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Date: Wed, 4 Mar 2026 10:47:50 +0200
From: Leon Romanovsky <leon@kernel.org>
To: Peter Colberg <pcolberg@redhat.com>
Cc: Danilo Krummrich <dakr@kernel.org>, Bjorn Helgaas <bhelgaas@google.com>,
	Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= <kwilczynski@kernel.org>,
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	=?iso-8859-1?Q?Bj=F6rn?= Roy Baron <bjorn3_gh@protonmail.com>,
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	Andreas Hindborg <a.hindborg@kernel.org>,
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	driver-core@lists.linux.dev, Jason Gunthorpe <jgg@ziepe.ca>
Subject: Re: [PATCH v3 00/10] rust: pci: add abstractions for SR-IOV
 capability
Message-ID: <20260304084750.GW12611@unreal>
References: <20260303-rust-pci-sriov-v3-0-4443c35f0c88@redhat.com>
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In-Reply-To: <20260303-rust-pci-sriov-v3-0-4443c35f0c88@redhat.com>

On Tue, Mar 03, 2026 at 04:15:20PM -0500, Peter Colberg wrote:
> Add Rust abstractions for the Single Root I/O Virtualization (SR-IOV)
> capability of a PCI device. Provide a minimal set of wrappers for the
> SR-IOV C API to enable and disable SR-IOV for a device, and query if
> a PCI device is a Physical Function (PF) or Virtual Function (VF).

<...>

> For PF drivers written in C, disabling SR-IOV on remove() may be opted
> into by setting the flag managed_sriov in the pci_driver structure. For
> PF drivers written in Rust, disabling SR-IOV on unbind() is mandatory.

Why? Could you explain the rationale behind this difference between C and
Rust? Let me remind you that SR‑IOV devices which do not disable VFs do so
for a practical and well‑established reason: maximizing hardware
utilization.

Thanks