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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.60.2 (3.60.2-1.fc44) MIME-Version: 1.0 X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 53C4EC000B X-Stat-Signature: 64g7xcigsrckhmuqetnmheof7h5d3nsd X-HE-Tag: 1787404826-36860 X-HE-Meta: U2FsdGVkX1+qi8czrTzVefslrR0om6MXWJy2VL0SF5dyRPmQOUZWYFS8CZqsInHDVlqvNAWViG5vD1SQ4nUPs8WfDRc24padnB7+fKkY8ScJ1OWBdXwhLcvElkvDATps9EQVqAv5TfBtBn6wwX6W7IHFx4pk0p2BJOtYZVc96aovi8xPe3dpfinCzWTvOLzRULKWGHxJhGK1BT1wWq6B1MtrPNnl6jfhGM/w18H+50DtQkU+OAbDRIHXqyH+0TGWBt2Xyb9PggTWRwX3V2YEgV2moLAldtXQSAanGnShCyAbsFBZeY0zoXakHXMkQOLPf0tY+Vxjh22MlWO6/VyeUTEMqVorRD//0eC+DdvAalwDbtppBFEMLUnOAZoFCaZt0NsQ2kiD2ZKjSsscldHuznPGnE+MiPrJjiSJ0zIEj5f2o3rzc0GP0x7qRd6SFkmj9XY0rVjcO6a+F1XNS+sDGbDTTrDn6gGcPTf7cGcK2LOey1eiSjPwnC0M7gjz2jJbEMWUmNEZbMWbaLkuxN3FrjvMw+C7r31ZxkaR/QEYFYn/knFsfZuuxG9FRjKhW+Amp91KgaoCx6tCapoRhAY12d+SR1nBRv+BQN+nEyOFe19tYJJVMIecMBZtHJxIzJclRZR0+qdihFP09eLRES1qmpccAmaY/CkfW2TKg7F5hQSMhJrD2GMk1r3XXNwvv5/lZtXPaIjALXshKjb/2qCoM8QBamhJ2GQ9pna3D8OcL32br1u197/NZkmmJWzcSQswNfpgSI0kZHTml8wGuNiNOmQ8foIlI8b6H5OkCaLNJiikOzyfzkpYKDD4xQZdFrYFGGVSBwr4rGo+d09vP2nq7jRzx0X9zP3lS65pzWPqDTqC9pfT2l3qX+kddp5dXjM8aD7/YFvzoRuShSxJo+6izNEiprHjq5GWwtreO5iUCMS+eFqjuO9RPTUorUmMYbjx+xQ2AFuiL3+MbioumWq 31hygdGh 6p6hLMq24BGUl+AUggb2s4hzx8JsEkjjAXUwazdMcMH8rZaQZWvrdxjzIToXHUkOBpWgaH9lFBUTY0Gl0VVDnj1+lNm55N2n7gsABNRKCrLsjYZ5tTjsWzDhaKfqNJlXlZkjw6AFRJd6Z9hJnhMPlouKiq6T7Iz6rWI4DWCNSzjBO9txbeFYBMWqDwvYJBdNrBvpErhibbAq1THSZSc42nXsdDwSopbxmRP4Wnv/4LEzaqNOwOuSkJQZKijazyjEqYQcUL3zL4QMno9SuTz/YIfxvo17uv9HOSzPMrR/8fEMfUf09Bv41NXpj70xzSH9F0NdB Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, 2026-08-21 at 15:04 -0700, John Hubbard wrote: >=20 > You have delved too deep, and now uncovered something that's been > a problem for the whole time. :) >=20 > Specifically, "no, GUP should not be setting folios nor pages > dirty", because that generally needs to be done as part of a > filesystem > coordinated set of steps. If the page is dirty, and the filesystem > didn't expect it to be, that leads to problems. >=20 > This is part of the big, remaining set of required fixes, that > launched the creation of pin_user_pages*() and related. Connecting > up the filesystems properly is yet to be done. And until then, this > is a real defect. >=20 Not just filesystems. I found about two dozen places where drivers fail to mark a page dirty after writing to it, after obtaining the page from GUP. I'll get out patches for that, unless there's some reason I shouldn't. --=20 All Rights Reversed.