linux-kernel - RE: [PATCH v2 1/4] iommu/vt-d: Block force-snoop domain attaching if no SC support

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]

Date:   Thu, 5 May 2022 08:34:09 +0000
From:   "Tian, Kevin" <kevin.tian@...el.com>
To:     Lu Baolu <baolu.lu@...ux.intel.com>,
        Joerg Roedel <joro@...tes.org>,
        Jason Gunthorpe <jgg@...dia.com>,
        Alex Williamson <alex.williamson@...hat.com>
CC:     "Pan, Jacob jun" <jacob.jun.pan@...el.com>,
        "Liu, Yi L" <yi.l.liu@...el.com>,
        "iommu@...ts.linux-foundation.org" <iommu@...ts.linux-foundation.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH v2 1/4] iommu/vt-d: Block force-snoop domain attaching if
 no SC support

> From: Lu Baolu <baolu.lu@...ux.intel.com>
> Sent: Thursday, May 5, 2022 9:07 AM
> 
> In the attach_dev callback of the default domain ops, if the domain has
> been set force_snooping, but the iommu hardware of the device does not
> support SC(Snoop Control) capability, the callback should block it and
> return a corresponding error code.
> 
> Signed-off-by: Lu Baolu <baolu.lu@...ux.intel.com>
> Reviewed-by: Jason Gunthorpe <jgg@...dia.com>

Reviewed-by: Kevin Tian <kevin.tian@...el.com>

> ---
>  drivers/iommu/intel/iommu.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index cf43e8f9091b..d68f5bbf3e93 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -4354,6 +4354,9 @@ static int prepare_domain_attach_device(struct
> iommu_domain *domain,
>  	if (!iommu)
>  		return -ENODEV;
> 
> +	if (dmar_domain->force_snooping && !ecap_sc_support(iommu-
> >ecap))
> +		return -EOPNOTSUPP;
> +
>  	/* check if this iommu agaw is sufficient for max mapped address */
>  	addr_width = agaw_to_width(iommu->agaw);
>  	if (addr_width > cap_mgaw(iommu->cap))
> --
> 2.25.1