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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?srAVRDklsGya7jVUey6m+MX+CCT8gJ1i7czKRrFrC715YWeLU2VwLxIonU5K?= =?us-ascii?Q?oU14xhPSPOYiTCg8Iskm9r09F61ZAx3Q7fdLHUTUP3VpIdnQ3ip34HNY75VR?= =?us-ascii?Q?oc2EGjfqvNKGCCY8kg6yvgGh17nLcBV/qEKzOr7D3keB81T+YKm4cF+1QGzA?= =?us-ascii?Q?95rKZxFVW3dBn7pnkdVNVcGglxRfvUMvdluvnme18kMa5+rb5Ez+oo9zgk/+?= =?us-ascii?Q?3s7pkLoULjr/Q38oXneDp9R/ql4XS1ruN2ZznEvCjPj6vWDA9pNPoNZsOFQa?= =?us-ascii?Q?7EyYa94a/BlDfrM6KVNGJircUCeHgFjH7fETxleT4DGfv9+L1pFZJPBvR0sO?= =?us-ascii?Q?9w/tg3qopGgrySUIoZ/kzyi7c4xP0xoIYu6h/B24rXuvlCXdG6gqBtg79DxT?= =?us-ascii?Q?N3u4sGkhzv5+5lMVzhsBUsITddxjQWhJXn8HlQkNLunDC+kWuzsuKwLMLtHP?= =?us-ascii?Q?4AHQ6LPXsGP81gysBE17KyjAghbBMvSkhUIsUlu0Om70idaMXS1+VoL9k/Fk?= =?us-ascii?Q?jpj0LrXGkCVYeIfK5d0Y2m/Nf2xPfiscuKFDhsASBpyQsAM5IiDO4nQZdaLP?= =?us-ascii?Q?oRZR/D2DDEvM1x1CGDGQkMNDXPzMfzE/DiWxN4PoSNV64Ni50JU9U/sBKj/V?= =?us-ascii?Q?8BVuaBDLhGvS/lUrsQUj+uLyXB8FfqBf9b7r3mJpKKK/aD4JeyxKVsTDEBP/?= =?us-ascii?Q?fEGuUodIRdLXFI51jlqi+FfRiDDjkgFQCNbrNW+AEnws2MT55zVSnRZjOZhg?= =?us-ascii?Q?MQr1Hc9CJfQ1MA1g+0fNcDFtg5yL77MCApb7EOa02Gp2X8XTrAisAzstED/W?= =?us-ascii?Q?nL+XcM3Ovs0JwE79CsTyjvzqrHj9nDJQGwvUHxO+VXOHWjb6ht+GY3XH7wzz?= =?us-ascii?Q?nKbr+FUQeUXgZSXGRe7kffBO56EcJMDuBxrjYopk4KfP18ttJoI21NHULNyJ?= =?us-ascii?Q?D/hs/6fId0kofdMjkmyA4ZO/gZ1yOGLKRpsIppeMIBpoNu0MP4/pZobSpeo7?= =?us-ascii?Q?0HBw7R9L9Eq0DV2sOZaH/2BxMa7gK6WzDRPE7KWiufI7UVFl+99wIA1ZUDKv?= =?us-ascii?Q?2RrZwGdQ+0LJApqtYnGcgeSEgtJzmV+ZShfKJJfdE0+m2WoSr4TJggo2KtbS?= =?us-ascii?Q?ZPceCKdAoJ5B+qKtJWoqwYcT9BE8fALQz1YX3tFlll1bVXMm0GVwuHVpP+WM?= =?us-ascii?Q?VDvkEjXoNC9x4VrajDb8lqjERQ6Mvkm1f5n6yFvp1wSuyB6e191z++4d5oAC?= =?us-ascii?Q?L+hVy39YkPeW1uvfTprhvWxwwm85XUCkWLejA75pKNI1/zWTbYvg5jMhGtEJ?= =?us-ascii?Q?XT0FZTqqfaAtu3PGANg29EbjTU+I12HqQiyP8308Ns+cyiS54oEReWncfxsd?= =?us-ascii?Q?aXeNHnpTPEocK4SF2iXL15whTWUMg/mvgo+1QY0TI6bIAcxF/UZcVSKN2BhL?= =?us-ascii?Q?4GdsTub10T29bA1JDszeIfaijHH/f7FSazUcjyNiPiCI18URunXpp9MSue9w?= =?us-ascii?Q?/vBh4qr21NyZFWsRwxHPszYAxrCjtcAKDbenNzL80PWC8bHMva8DUF5JXdt+?= =?us-ascii?Q?FVh3++dWorWC/RkuRXUp6vSgcq1WDD4q/IgGIgwqCtv3qAWpToeseucrgIYa?= =?us-ascii?Q?gg=3D=3D?= X-OriginatorOrg: garyguo.net X-MS-Exchange-CrossTenant-Network-Message-Id: 41979c8f-3c29-4958-020b-08dcd51850e4 X-MS-Exchange-CrossTenant-AuthSource: LO2P265MB5183.GBRP265.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Sep 2024 23:52:40.0001 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: bbc898ad-b10f-4e10-8552-d9377b823d45 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: vtLSBwW/iDRIW4hiMjMaJKLRcPAYUIqy7Zfx9uHUkytsGSV2UjqSswkpkpYk5uzBpDgR0qDgfZ7Ex2EkEunEzQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LO6P265MB6476 On Fri, 13 Sep 2024 19:51:01 -0700 Ramon de C Valle wrote: > Since we're doing this, may I suggest that we use > https://crates.io/crates/cfi-types by reexporting them as kernel::ffi > instead? By using those, we would also avoid the granularity loss of > normalizing integers and using the integer normalization option > wouldn't be necessary. I could accept any > contributions/kernel-specific changes that would make it easier for > the kernel to use them. I don't think integer normalization is a big issue. Sami said the granularity loss only results in ~1% reduction of unique type hashes in https://lore.kernel.org/all/CABCJKuc8ue1y7WBPo3YRRoDeGUFpRon4at=Wa1rQjrXzOGpt9w@mail.gmail.com/. As Alice said, if the CFI annotation works with type aliases then we should switch to use them. Without it though, I think it's quite inconvenient if we have to use new types for all FFI integer primitives and add a ton of conversions. I'd prefer we still use type aliases. Best, Gary