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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?3RxdKyI9S700hv6QEpGowuxYtipHAB1lWrba34E7zghLzIjmAlUiuUIrb7a7?= =?us-ascii?Q?y/ukyVat++896pNxEqAkTrjCqFsMiPg//OubfNO6kbk1u2XoiEkuBP19KIiF?= =?us-ascii?Q?x5dsFqVRrK/2kKI0abWiIB5YgIulKCcpoLIWPGluPfHtqf0ixCrXLRw8H/eb?= =?us-ascii?Q?0WL74xOLCIw+S4dLYh9JPtMr/RWpglqz67NPupEYYjeduyRcVeNO5Nwg1aIW?= =?us-ascii?Q?QwlgGwQ4rWeJ4zt4xCE8iXVBzJGsiuZpVkPeDBteb/tV/mInDiD0StdWW9sQ?= =?us-ascii?Q?l4XoktCi5eXRB2NIsYQR3WHVKrjD4c+0eun7RgcCQ6X2HRi8Oe/kV1neurtr?= =?us-ascii?Q?l0QUzl4RLpXNyPKUKjjfvy5QYw6n7CPbz3gD7ea5jnoJxcbckNHR+P+Q+gMA?= =?us-ascii?Q?XRNYm0/QzfIWwkU7aNwP52Q8nh9JJgdkhoZzacuxRxVlNjqbBPD/j3khsDBi?= =?us-ascii?Q?BmPeKdvblk78VXdaVHVqul1er59l1PQyiE9pv2PcqwgxHXnGG2+TONBTeyqJ?= =?us-ascii?Q?VurjXWeidClWIJ/PebHtYrP/rbGHvM2tM04MHWxl/bn6EdHenMHhC/irqV35?= =?us-ascii?Q?+8UV7gP3axijUxtfb/RDAnEbDazJtoACXkxGdpXTXsPUSchKnWCvH6Ij9CB8?= =?us-ascii?Q?V3ZEz7TwP/nLAX8NKbvLqEpNfvYhgJaDUPIXaBJT9/mCfS/UpelXH1hZErqC?= =?us-ascii?Q?xdckr6nlM1LwMon1W6nvPooJyT89KMXlmUcS5YPBKQ3207i/DEOsxS1qNzeo?= =?us-ascii?Q?hhppkG6Ae+C9jEQv8eYRQRuoQiXV/RPTxs5rCOgwcU0qQEdxkOoyDsc5Yqwq?= =?us-ascii?Q?5tJQJ7kuklfaSue3JJ4rDzXleFrmVgvmUv+u26k2OOWAhYqoMojJ2WHBT18e?= =?us-ascii?Q?E7zaiCmLc8zk2T9CV5hXaJaL2Ih2znt1H7S+zpySVuwM3uVN0HyLJdb46O+1?= =?us-ascii?Q?mzAwoGwKUvlIhK8ZvdEmZw94ugMHKkpThCHsiPCYEeBx/Ie2rDV4jN2FMo+e?= =?us-ascii?Q?cROYjHRaSfW7eigGWSmGN0jtIBCHEV4tGi76AkCaigFetiOVWcfK0anfRJYY?= =?us-ascii?Q?kzNCtaZZPdZ5T5iFG22eDqylf+6csEywcIqxPlih7nPKuiIH3lgEVaC9W3a+?= =?us-ascii?Q?peoN6KeMUB1y7onu5oAxOkZghMz0fgsjLoUetmMZPlRp3DsyA5gict4v0cxB?= =?us-ascii?Q?pSHa4XCMz0h6+Fjb6vWGYkCVQ0+MXjhg/+iQzx731c8vqewwgNceGpuJRo9Z?= =?us-ascii?Q?w2EI9k5NqBNKRwk/DGyS4JLdVSImAMAaNv26vdGwjUhnQ0a0bXLsurDC/Xkn?= =?us-ascii?Q?6jUNHvh1TtUo+KXmtz54/fZ4KNBQCRUQT+dyuZIAK4j6WxKkNaw/jeUZToNS?= =?us-ascii?Q?wGQQJFexZqkd9rzSNu5xLQzM2CG5I1eF0b0I7WEQS1hW0Vhch2DH6vatvi6h?= =?us-ascii?Q?cJW4IEv1+cNiYUTUiMpraQ53bFfmq9fW+mAXd4jw4Xkhp3za/MBAC7szEg6w?= =?us-ascii?Q?0N32U1UFSU5j18vuFjvBEpcFySwRqUc2aabwZh9Rk+w7cayHQ0E50LzDEpJe?= =?us-ascii?Q?4djU5q1gJ0Yd0vmiFHi5UhXC/wFA6kBZhyLqFbn1uL9Jzgo3ZJ0nKdxFB+iG?= =?us-ascii?Q?0JItiq+mDvTBskP/X+6CaVw=3D?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9119df1e-c877-4e66-d426-08d9bbdcd830 X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5600.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Dec 2021 12:59:04.6152 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: f7a17af6-1c5c-4a36-aa8b-f5be247aa4ba X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: UHFKfSqDQ4lgCjSTHfX/73UMt18oCz3O/yA1hjS2W8WoJDiKvVQCf25ROS2shajYZzk9cqXOxH+x7APBwWASYw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR0402MB3392 On 10.12.2021 13:05, Roger Pau Monn=C3=A9 wrote: > On Fri, Sep 24, 2021 at 11:51:40AM +0200, Jan Beulich wrote: >> In order to free intermediate page tables when replacing smaller >> mappings by a single larger one callers will need to know the full PTE. >> Flush indicators can be derived from this in the callers (and outside >> the locked regions). First split set_iommu_pte_present() from >> set_iommu_ptes_present(): Only the former needs to return the old PTE, >> while the latter (like also set_iommu_pde_present()) doesn't even need >> to return flush indicators. Then change return types/values and callers >> accordingly. >=20 > Without looking at further patches I would say you only care to know > whether the old PTE was present (ie: pr bit set), at which point those > functions could also return a boolean instead of a full PTE? But looking at further patches will reveal that I then also need the next_level field from the old PTE (to tell superpages from page tables). Jan