[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <0ea819d9-1169-48b1-8579-3a054a0bd077@intel.com>
Date: Wed, 8 Nov 2023 15:45:17 +0800
From: Yi Liu <yi.l.liu@...el.com>
To: "Tian, Kevin" <kevin.tian@...el.com>,
"joro@...tes.org" <joro@...tes.org>,
"alex.williamson@...hat.com" <alex.williamson@...hat.com>,
"jgg@...dia.com" <jgg@...dia.com>,
"robin.murphy@....com" <robin.murphy@....com>,
"baolu.lu@...ux.intel.com" <baolu.lu@...ux.intel.com>
CC: "cohuck@...hat.com" <cohuck@...hat.com>,
"eric.auger@...hat.com" <eric.auger@...hat.com>,
"nicolinc@...dia.com" <nicolinc@...dia.com>,
"kvm@...r.kernel.org" <kvm@...r.kernel.org>,
"mjrosato@...ux.ibm.com" <mjrosato@...ux.ibm.com>,
"chao.p.peng@...ux.intel.com" <chao.p.peng@...ux.intel.com>,
"yi.y.sun@...ux.intel.com" <yi.y.sun@...ux.intel.com>,
"peterx@...hat.com" <peterx@...hat.com>,
"jasowang@...hat.com" <jasowang@...hat.com>,
"shameerali.kolothum.thodi@...wei.com"
<shameerali.kolothum.thodi@...wei.com>,
"lulu@...hat.com" <lulu@...hat.com>,
"suravee.suthikulpanit@....com" <suravee.suthikulpanit@....com>,
"iommu@...ts.linux.dev" <iommu@...ts.linux.dev>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
"linux-kselftest@...r.kernel.org" <linux-kselftest@...r.kernel.org>,
"Duan, Zhenzhong" <zhenzhong.duan@...el.com>,
"Martins, Joao" <joao.m.martins@...cle.com>
Subject: Re: [RFC 3/7] iommufd: Add iommufd_device_bind_pasid()
On 2023/10/10 16:19, Tian, Kevin wrote:
>> From: Liu, Yi L <yi.l.liu@...el.com>
>> Sent: Monday, October 9, 2023 4:51 PM
>>
>> +struct iommufd_device *iommufd_device_bind_pasid(struct iommufd_ctx
>> *ictx,
>> + struct device *dev,
>> + u32 pasid, u32 *id)
>> +{
>> + struct iommufd_device *idev;
>> + int rc;
>> +
>> + /*
>> + * iommufd always sets IOMMU_CACHE because we offer no way for
>> userspace
>> + * to restore cache coherency.
>> + */
>> + if (!device_iommu_capable(dev, IOMMU_CAP_CACHE_COHERENCY))
>> + return ERR_PTR(-EINVAL);
>> +
>> + /*
>> + * No iommu supports pasid-granular msi message today. Here we
>> + * just check whether the parent device can do safe interrupts.
>> + * Isolation between virtual devices within the parent device
>> + * relies on the parent driver to enforce.
>> + */
>> + if (!iommufd_selftest_is_mock_dev(dev) &&
>> + !msi_device_has_isolated_msi(dev)) {
>> + rc = iommufd_allow_unsafe_interrupts(dev);
>> + if (rc)
>> + return ERR_PTR(rc);
>> + }
>> +
>
> Only MemWr w/o pasid can be interpreted as an interrupt message
> then we need msi isolation to protect.
yes.
>
> But for SIOV all MemWr's are tagged with a pasid hence can never
> trigger an interrupt. From this angle looks this check is unnecessary.
But the interrupts out from a SIOV virtual device do not have pasid (at
least today). Seems still need a check here if we consider this bind for
a SIOV virtual device just like binding a physical device.
--
Regards,
Yi Liu
Powered by blists - more mailing lists