> -----Original Message----- > From: Joao Martins [mailto:joao.m.martins@xxxxxxxxxx] > Sent: 29 April 2022 12:05 > To: Tian, Kevin <kevin.tian@xxxxxxxxx> > Cc: Joerg Roedel <joro@xxxxxxxxxx>; Suravee Suthikulpanit > <suravee.suthikulpanit@xxxxxxx>; Will Deacon <will@xxxxxxxxxx>; Robin > Murphy <robin.murphy@xxxxxxx>; Jean-Philippe Brucker > <jean-philippe@xxxxxxxxxx>; zhukeqian <zhukeqian1@xxxxxxxxxx>; > Shameerali Kolothum Thodi <shameerali.kolothum.thodi@xxxxxxxxxx>; > David Woodhouse <dwmw2@xxxxxxxxxxxxx>; Lu Baolu > <baolu.lu@xxxxxxxxxxxxxxx>; Jason Gunthorpe <jgg@xxxxxxxxxx>; Nicolin Chen > <nicolinc@xxxxxxxxxx>; Yishai Hadas <yishaih@xxxxxxxxxx>; Eric Auger > <eric.auger@xxxxxxxxxx>; Liu, Yi L <yi.l.liu@xxxxxxxxx>; Alex Williamson > <alex.williamson@xxxxxxxxxx>; Cornelia Huck <cohuck@xxxxxxxxxx>; > kvm@xxxxxxxxxxxxxxx; iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx > Subject: Re: [PATCH RFC 15/19] iommu/arm-smmu-v3: Add > set_dirty_tracking_range() support > > On 4/29/22 09:28, Tian, Kevin wrote: > >> From: Joao Martins <joao.m.martins@xxxxxxxxxx> > >> Sent: Friday, April 29, 2022 5:09 AM > >> > >> Similar to .read_and_clear_dirty() use the page table > >> walker helper functions and set DBM|RDONLY bit, thus > >> switching the IOPTE to writeable-clean. > > > > this should not be one-off if the operation needs to be > > applied to IOPTE. Say a map request comes right after > > set_dirty_tracking() is called. If it's agreed to remove > > the range op then smmu driver should record the tracking > > status internally and then apply the modifier to all the new > > mappings automatically before dirty tracking is disabled. > > Otherwise the same logic needs to be kept in iommufd to > > call set_dirty_tracking_range() explicitly for every new > > iopt_area created within the tracking window. > > Gah, I totally missed that by mistake. New mappings aren't > carrying over the "DBM is set". This needs a new io-pgtable > quirk added post dirty-tracking toggling. > > I can adjust, but I am at odds on including this in a future > iteration given that I can't really test any of this stuff. > Might drop the driver until I have hardware/emulation I can > use (or maybe others can take over this). It was included > for revising the iommu core ops and whether iommufd was > affected by it. [+Kunkun Jiang]. I think he is now looking into this and might have a test setup to verify this. Thanks, Shameer
