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b=QguOXzMUipQp+iM/hLVW4Fwx3UloBoYNYsLTOx7a+nVx7MDyX0iy6bIK74IhAeO4wG5AEk oKa37FvjvVLQ+vsAVSQq97Z0fXXm14QivR1U7sQRQ++qp5hugXLAA6ymWRGFb2bs3aPgXF ro9NCz12kw0bWy/c4nD4px4asYBh26Y= X-Stat-Signature: 1qfp6tpi3zbwiq97z373sxn6c9aiqnr9 X-Rspamd-Queue-Id: 3C339100092 Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=Nvidia.com header.s=selector2 header.b=mJ8NYbE+; dmarc=pass (policy=reject) header.from=nvidia.com; arc=pass ("microsoft.com:s=arcselector9901:i=1"); spf=pass (imf05.hostedemail.com: domain of rcampbell@nvidia.com designates 40.107.243.68 as permitted sender) smtp.mailfrom=rcampbell@nvidia.com X-Rspam-User: X-Rspamd-Server: rspam01 X-HE-Tag: 1658771783-728531 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 7/25/22 02:32, Alistair Popple wrote: > Ralph Campbell writes: > >> If hmm_range_fault() is called with the HMM_PFN_REQ_FAULT flag and a >> device private PTE is found, the hmm_range::dev_private_owner page is >> used to determine if the device private page should not be faulted in. >> However, if the device private page is not owned by the caller, >> hmm_range_fault() returns an error instead of calling migrate_to_ram() >> to fault in the page. > /* > * Never fault in device private pages, but just report > * the PFN even if not present. > */ > > This comment needs updating because it will be possible to fault in > device private pages now. > > It also looks a bit strange to be checking for device private entries > twice - I think it would be clearer if hmm_is_device_private_entry() is > removed and the ownership check done directly in hmm_vma_handle_pte(). > > - Alistair I'll fix this in v2. Thanks for the review.