netdev - Re: [PATCH RFC] pci: Control whether VFs are probed on pci_enable

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20141207184242.GA24790@mtldesk30>
Date:	Sun, 7 Dec 2014 20:42:43 +0200
From:	Eli Cohen <eli@....mellanox.co.il>
To:	Yuval Mintz <Yuval.Mintz@...gic.com>
Cc:	Eli Cohen <eli@....mellanox.co.il>,
	"bhelgaas@...gle.com" <bhelgaas@...gle.com>,
	David Miller <davem@...emloft.net>,
	linux-pci <linux-pci@...r.kernel.org>,
	netdev <netdev@...r.kernel.org>,
	"ogerlitz@...lanox.com" <ogerlitz@...lanox.com>,
	"yevgenyp@...lanox.com" <yevgenyp@...lanox.com>,
	Donald Dutile <ddutile@...hat.com>
Subject: Re: [PATCH RFC] pci: Control whether VFs are probed on
 pci_enable_sriov

On Sun, Dec 07, 2014 at 05:05:06PM +0000, Yuval Mintz wrote:
> 
> >This can save host side resource usage by VF instances which would be
> >eventually probed to VMs.
> 
> >Use a parameter to pci_enable_sriov to control that policy, and modify
> >all current callers such that they retain the same functionality.
> 
> What's the end-game here? How eventually would this be controlled?

You can probe any VF at the hypervisor through sysfs files
(bind/unbind). You can also pass them through to a VM. Nothing
changes.

> 
> >Use a one shot flag on struct pci_device which is cleared after the
> >first probe is ignored so subsequent attempts go through.
> 
> Does a one-shot flag suffice? E.g., consider assigning a VF to VM and
> than shutting down the VM. Assuming this feature is disabled,
> the VF didn't appear on the hypervisor prior to the assignment but
> will appear after its shutdown.

Sorry, I don't follow you here. Please clarify.

To be clear, the functionality proposed here is really one shot. It
just prevents calling probe once; besides that nothing changes.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html