linux-kernel - Re: [PATCH v6 7/9] iommu/amd: Update domain into to dte entry during device driver init

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: <20161110114816.GE9996@8bytes.org>
Date:   Thu, 10 Nov 2016 12:48:16 +0100
From:   Joerg Roedel <joro@...tes.org>
To:     Baoquan He <bhe@...hat.com>
Cc:     iommu@...ts.linux-foundation.org, linux-kernel@...r.kernel.org,
        kexec@...ts.infradead.org, Vincent.Wan@....com, dyoung@...hat.com,
        xlpang@...hat.com
Subject: Re: [PATCH v6 7/9] iommu/amd: Update domain into to dte entry during
 device driver init

On Thu, Oct 20, 2016 at 07:37:18PM +0800, Baoquan He wrote:
>  	prot = dir2prot(direction);
> +	if (translation_pre_enabled(iommu) && !dev_data->domain_updated) {
> +		dev_data->domain_updated = true;
> +		set_dte_entry(dev_data->devid, domain, dev_data->ats.enabled);
> +		if (alias != dev_data->devid)
> +			set_dte_entry(alias, domain, dev_data->ats.enabled);
> +		device_flush_dte(dev_data);
> +	}

Hmm, I really don't like to have these checks in the fast-path. But to
get rid of it I think we need to re-work the way domains are assigned to
devices.

One way to do this would be to add a 'defered-domain-attach' feature to
the iommu-core code. What do you think about this?


	Joerg