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dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from IA0PR12MB8374.namprd12.prod.outlook.com (2603:10b6:208:40e::7) by DM6PR12MB4140.namprd12.prod.outlook.com (2603:10b6:5:221::13) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.592.11; Tue, 10 Nov 2026 16:24:09 +0000 Received: from IA0PR12MB8374.namprd12.prod.outlook.com ([fe80::d85f:4c87:ae84:3f16]) by IA0PR12MB8374.namprd12.prod.outlook.com ([fe80::d85f:4c87:ae84:3f16%6]) with mapi id 15.21.0615.007; Tue, 10 Nov 2026 16:24:09 +0000 From: Zi Yan To: "Kiryl Shutsemau (Meta)" Cc: Christian Brauner , Alexander Viro , Miklos Szeredi , Amit Shah , Jan Kara , Linus Torvalds , "David Hildenbrand (Arm)" , Matthew Wilcox , Bernd Schubert , Hugh Dickins , Baolin Wang , Andrew Morton , Arnd Bergmann , Greg Kroah-Hartman , "David S. 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?KfiV0texI8BFXsg2ql3DdG3tVClLbc0/GlFXRnGlc22TDCwG0lfGZuivjlqP?= =?us-ascii?Q?kN/bmzKiSbwnHYZA6lSinQRSf7p1UEHR0Ul6r7nIyQrkOVGG/cIlASDCrko+?= =?us-ascii?Q?HjjkR9s6wRFj07gFrgGoETrh2j8TKG17+WKCC/eM1Q5uzUoLjR2Nqcx9FJ5b?= =?us-ascii?Q?TqPfXyeYqvDz1SQ0biMR0bRIrxRdzKmtCwzt4YATQPbcOcJUp/xeIZ76aFpD?= =?us-ascii?Q?KWT/zxMD+i0XHS2k5fPnh5g8C4bphJIg5CGgEE67zmE/rs0SBlx1QsMQvyjX?= =?us-ascii?Q?ZJaASxLL4zWXNT8N+iJo6L/ZojzB8XNA+fuYMlFupGMpKBsx9z/op+puf/8+?= =?us-ascii?Q?C5yeUcNEKbjKBuCHN6ElDrq26w9Li6A6o8xXEIhgY3lF+iczGUJgOLcneXA9?= =?us-ascii?Q?FVa2r50xp3et4FJxIph+1JfGkk+EMPfhihIVNn28icFIqIeSSvgh5bMlg65r?= =?us-ascii?Q?Rp1hsTksyvOHKaYX7isJNKfF+TqgkB95iOZpMTFbY3W972DHDf11ExBV7GpD?= =?us-ascii?Q?k70tcK1A9eeqA8wUxt/Jz/QVBhgODbKx070FgwBw67KYL/tVxh6u0zhi1tu3?= =?us-ascii?Q?CVGH23vfKxj9yiNgIDFAdNnfuzVPL+ME4wwzMel4iavDFfz/Cu18vLahXceO?= =?us-ascii?Q?qbs/APTlIf1WYgB8yzDy5txIvhN3VPCC8fL0PrCdM1IMbvWtO/8YhVDxa5Eb?= =?us-ascii?Q?WcFeQrmUwfpiTCRRdrpDErkcyYkQ5BH/SgDaBh1FYUCK3P78/qJXlbP+MRtO?= =?us-ascii?Q?vWBGXC978vVyKZpE0Z5y4QdGKyJDAHbwS7zicVtpchTQhvmhiZnILv8GOco3?= =?us-ascii?Q?MRyNiH/rcG4NTxXpcXGdJhhGwMAQjbxfENQsJNs7m6QaVp1YZnqLn6jyUJZl?= =?us-ascii?Q?8XlPc66rZc6c54HPadIJjgQCOuNJ94x1JhEBGHG+U2FwImoMswmKttP/GWj6?= =?us-ascii?Q?x/BnABMK+ThNJCV7kkbZ3VRgaT1jXVtOvA1K/rvByv/ZypfGORSq2D1QakfV?= =?us-ascii?Q?j4JYwhn5mhpyhzLtMPsFLmwrz93Y2y9DS0zBLBtn3bRLsIzKYcNCKMLTRZAZ?= =?us-ascii?Q?k+8GyUEHq/LzGc3dv7onUc7sFD9YYlHDe8rQAiSUVYK58RrAKPdhnNh7dCfo?= =?us-ascii?Q?dpBwtbVcuS0PGbbUXzg8WFSO+xkvyWP81gUbDQJofgINpIBfVzvK0s11GT8S?= =?us-ascii?Q?gS9lG+GjyDuyOeNS/ygqRjD0JE9eifj0vSiCsIWa8lJoHZh1heSD9e8vhVhF?= =?us-ascii?Q?Q8Lat3YX4N7OkzueuHTHRRreBLqC/dcL3o55Etan8RPCUq53XteYgE/SgZUA?= =?us-ascii?Q?rfDj84Z1viNBPM/oR1D9aVwOMOA0bXLnOGoZ9n+bu5gN8MZ8Y8qWo7eJWOMY?= =?us-ascii?Q?QQmIjVaZ807sDH3rikx5wqOL/y0pOc2jbFwjwvzIoIAoCaP8grVW+N5wI3By?= =?us-ascii?Q?yI4pR0UhfHK3dXMPOsRwioAvafaniyJaZl1phucmsdYQrwr3BboxMXTp1QkH?= =?us-ascii?Q?IG9p9IcYsv/1120gmA/rDApL6e8PrSUK51u83Bj05+SL9Yfd4lHJRMsPMN+9?= =?us-ascii?Q?IsMn1BH3+CRXiGJdv/VvOorZkc3fsPR/IzH84jaZC5wjq0FgyEx6sUTj7d3O?= =?us-ascii?Q?Un7+4d0hyg9ILgZFfERTclcP3mw4tXD+kbodsHp/z+uw2kLWx189aVTDnsOM?= =?us-ascii?Q?BEqbyLhih+QACjUf+S5Sl4P1q4fUC3H/YmlXcgG5EkdYPeue?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: bbc436b7-fc16-43c1-36ff-08df3f470c37 X-MS-Exchange-CrossTenant-AuthSource: IA0PR12MB8374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Nov 2026 16:24:09.1474 (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: 1NQOzA7teSmq/wxM/Oktyi0JtVcP6LAIiDw3gDeS4ADTf0UyiZakIAWLVcDMcy4U X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4140 On 10 Nov 2026, at 9:52, Kiryl Shutsemau (Meta) wrote: > pipe_to_sg() tries to steal the page of each pipe buffer and pass it to > the host as it is. When the steal fails, it copies the data into a page > of its own. > > Pages written into the pipe with write(), gifted user pages and page > cache pages can be stolen. The ftrace ring buffer pages that > virtio-trace splices cannot, so that in-tree user always gets the copy. > > Always copy. The data that reaches the host does not change. > > Preparation for removing ->try_steal() from pipe buffers. > > Suggested-by: Linus Torvalds > Signed-off-by: Kiryl Shutsemau (Meta) > --- > drivers/char/virtio_console.c | 39 +++++++++++++---------------------- > 1 file changed, 14 insertions(+), 25 deletions(-) > LGTM. Acked-by: Zi Yan Best Regards, Yan, Zi