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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?sqSkjuJ7hS9GHPImjJSY3gJKqjbeE0nhB+ztqqjqnWaP0lBum4MS62ojN5YE?= =?us-ascii?Q?8PJIg9aOq52/S8AFt1CgRiu9Fos8Rmuo7HqgytRdiQ+IOuEfdURbPb+QIefL?= =?us-ascii?Q?8Tgknx1tFykDxaO55SWGu3zCR8B6ZttViB5N7zFNqLiSXuI8XTRsCvGaumTt?= =?us-ascii?Q?tOeIPF0LZEYO7vuwYsL2h8cW7AtKyfsWZqj1szpNUIEN0MlxgSdv1Hci/RbR?= =?us-ascii?Q?ZN/izfQK9ASp0xo8t5bX9I9RDNqU45XztrL97W+xm2fBHcsG7BshbQjDrG07?= =?us-ascii?Q?R1jyx259uKee3aG0HpI2y5MlPzQTbv57pS6Pzobrc9CJUPYe+zPb/HjN0aDj?= =?us-ascii?Q?xoz3AOOtmTjFgsbHptwPGMyX09Wt99a3H4lOg4KsqtUJioHztDasW5sWZJgB?= =?us-ascii?Q?Z72xxCf0JVhPR8qGYhdyN3nVDLmpc2jh3C2f6aCcvTMJQ/LXF2NdGZnLfHmD?= =?us-ascii?Q?q+iLKXUf2mZkc9ptM1kEY8XWIivbXo4CiRp9HQfYdeJ0VlEIBu3ZGsM+b2w0?= =?us-ascii?Q?eHPld4yD2Jl/vcdJR3fzO+uoZv0CjVaWykUsvzn33rEiNR3wm3wlZKZcssNJ?= =?us-ascii?Q?qXf0NZDm0GT8aQXAyxnwIZZF3GqWlAN9HH8dTci5Iuf5JNki6HKDxRyImwU9?= =?us-ascii?Q?36qp58hHMd7dbqxb6ZHGiVPvWyxqTgYDlMtxPhO1cpbgjqt83ARn9KT+vSpN?= =?us-ascii?Q?xBoXrEVAFXaqovWUm3TUbMmyzjS0t+PVGgTnC0qC1CLLeqzGZKaUn/3WqzX9?= =?us-ascii?Q?vKNLSYuIJGF5AycUaPCh+Z7cWaenN0IDZgHO6AdJemY0S+q/SzeXrXVQ9byJ?= =?us-ascii?Q?g9fboWYvcASo3e21WWWE+veByOYk72MOGph3GQaAMyLvVZ/N34ZAcAnbA3eo?= =?us-ascii?Q?HMcu9wBwGT7X3CSjiaKUN+b+n3HWZ5A7INZpzq5In004LWV35A14pjEeuZcC?= =?us-ascii?Q?JcQReCP3Vw27lJTQrkxoFC43X1lAkOQi6s1NfDHTtOJGn0zfS5NbNKmNcdEK?= =?us-ascii?Q?4YB2onkdlw5lqFY4zQ9vRLJVY89oEqtvBs5azbGNn3tQTeDH2SOfp+zcFYP2?= =?us-ascii?Q?2oCvX2pUxJqNGj89GN9lMCky1XKkhVBIUGLkj/cQ8DSzNSr/M/dPQAIujv9V?= =?us-ascii?Q?fH2ko40dx3zbviHiK1yEnNXisOpGjBzgzvX561bshmTMPPX2783GrxJR7ZBz?= =?us-ascii?Q?WOwBjq2PvOX5MsXycMvJiN9b7qowA0iwpF6eORUJ7y7pXXCVJ304pdHjEd2v?= =?us-ascii?Q?Ejjiz0qEo06ZqiOm717YJuigr2l6Rnl5FuhrwUIU0P5aobopPmp2qIG4h/y0?= =?us-ascii?Q?PPBGtLZ1ft4PIm3H3tTQzW2rC4E12MU4oClkByfjXUgeuacBmuh77lzFzUDm?= =?us-ascii?Q?qCMIO1j7TCenE2lXfO2Kz2/zZsNhLineDNUV57pHSdXb+mzvWeKERzg/KeM5?= =?us-ascii?Q?dy4ylHgYrOYp2OCv1Gk6ZIGdbLaE2b6zFjxOIAqnKmm1ueYZWCIKyBpuRxaX?= =?us-ascii?Q?ikt/CQrQ5JMeP5BoZf4V2pHN33TaNp8d7/QZbsBcJb3OcQepbOOGAd/93FZi?= =?us-ascii?Q?qd91iV3YsoTaLEpSEkMohZoTSZoVPIN5G2hnuk2Y?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 53b13440-1c1f-4d5b-d0cc-08dadead95ee X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Dec 2022 15:03:55.4229 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: QGIzK6873wP6I3B5hEq1iXBk6U1xOn+7xK/+0QDfclvrq03Cx8srLDW9izRl8DCU X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB8120 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Dec 15, 2022 at 09:38:42AM -0500, Steven Sistare wrote: > > I'm not sure this is quite, right, or at least the comment isn't quite > > right.. > > > > The issue is that the vfio_dma does not store the mm that provided the > > pages. By going through the task every time it allows the mm to change > > under its feet which of course can corrupt the assumed accounting in > > various ways. > > > > To fix this, the mm should be kept, as you did above. All the code > > that is touching the task to get the mm should be dropped. The only > > purpose of the task is to check the rlimit. > > Yes. While developing my "redo" series I tried it that way, but did not post > that version. Functionally it should be equivalent to this series, but I can > code it again to see if it looks cleaner. The big reason to split is that this existing bug pre-dates the vaddr work and should probably be backported further. It can be triggered just by doing exec.. Jason