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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?5bz6TTRs9EQhZML/6/bBtMTy08dngOeTkTRbYwLA42spIbizPkmX1MiRxHDw?= =?us-ascii?Q?AYSLWdDdJiGFxUp9lYuHuvKeE5Id+2OdY9rFvRfndqZsWusB0BFE1T8YyYcu?= =?us-ascii?Q?oYHYv7s7ybuj1wEb+sPjOcZ6CSVQjExWOoNveWJEnWwiR2O6e9Ij3XojQIpI?= =?us-ascii?Q?T130btnx0hqeOEu31jgzgBJv9EDM54S1VweMu1kitBFUpHchlrjqdA/zCQxC?= =?us-ascii?Q?HgaD3aaCqL2ANJEAxRReDh2pCvT68OZJAE94++rruvsa/PS8HOWdL+glPbQh?= =?us-ascii?Q?qRInTVcfygoBerfOYge9qhq/VU9Qh2Qrq1cV27LdBU9v548pD8GhEsRmeLd+?= =?us-ascii?Q?SiHECiVNKLlgBIQsyKAI3fezDG9S2HkNIvUDJi1ixMP9I2d8LYVxyHKME1oQ?= =?us-ascii?Q?s5jm2u4Lhyccf2rCvziOfvLSz0i3pdZD+CjQJkz78xTeTC8GPSMLQT//f74T?= =?us-ascii?Q?Z1RbND7/jegB7BEiE5okfL+BEIdKAMKIdO8zZjo0VzJrQuu6xcKbkEAO5BN/?= =?us-ascii?Q?+zRi+fuQ3ajw7W+IO/iH9U9RzZD9jNqEsQiU0V7LmABKtdPZfvUNhjXL7am+?= =?us-ascii?Q?9ntukcsZPB9tSpVCUxrUplLwZvjRD8G5k35v7nSKX1fa+zTvjJldPQf3clIc?= =?us-ascii?Q?RLcMtJBVeADEj0JULomo7BAYBz3cvESYJwbhXdxHaLLOta9pwXOheln9yzuk?= =?us-ascii?Q?We78nlDmeUojlxNNfVAiiOgdsEufHinh4di/knH6JSm/G80ZVC1grHPtVc/X?= =?us-ascii?Q?37r3MWOiU+d1FleZsBXgoW9vWGutueqR/+0iyhbv87KigBmw1Brcsm2TrWrk?= =?us-ascii?Q?3KUDYYw6MOfAg5Rz3kxePiDMnFb+7Ltmk29yrzptgyNYpdqslrlOddezildL?= =?us-ascii?Q?kEksZH3mMna0p0J1b4KzsJEIjX/9MPjlO/PpvPJisko7bMvRVEYvTb/UgKpH?= =?us-ascii?Q?dC5F3/ioi/RbbRxVE6GKFf6wyuULMV3pzKunkJ9LUyr4Xx6tNBK5YkctXjsr?= =?us-ascii?Q?IlxbOVjYw2hyY7M6iSfdS8m1a5DIK2VvKkO5n/QvIiH0OczYuvaA9UD9eHe2?= =?us-ascii?Q?IkLj66X383TQEOQiX1P/Wtx8b8lhAHoRYZt6Ml6QZwoRxDBsmC1vlQwrriDG?= =?us-ascii?Q?t5sfg0DTFe3OTwXDlPS1NLmjSye0PYGwhwz09bazZPviDR93PtHtZ+1iHT/L?= =?us-ascii?Q?r3ehBjF3lg3pZ/vWgpGhzzOu2rZUY64V1yVRrPa7ruyqUmXZ2iy4NMsKdv98?= =?us-ascii?Q?jeamce3S0f28dC0vpUVu1OW1LzDjjEWGynB17DF8yegOuZFu9ZDzFPg+ZN/9?= =?us-ascii?Q?ElSH+1vQcpcrHjD4XbLXrQH2r/Vy1uB6AOvi5O/mkC+tGwkYiyAj7yFiyyVd?= =?us-ascii?Q?ijsX3d6adjjWyTJVBkt/fXCK2Tpu6ZCTg+XH5JMGHe4coWwnD8oOqTQwtVB6?= =?us-ascii?Q?RWIxczBUJHVfySoR2c21qVU2vGHyBsx2uVaclSzYCdRgJ6ASEUm0FcRga62t?= =?us-ascii?Q?3fkVGqjmN4W77CjqzssvjiQ5/Eu3BhDe4MZoam09vOpLRDEKqsXw/cRDXLid?= =?us-ascii?Q?1TGz1u7LsCT0+eUQX2s84vQSIN1RMVfBvcYlmf1M?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: eddc090e-e898-4e07-63c5-08dd8bed3486 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 May 2025 15:55:06.3763 (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: 1d3KRD0BC8NNvgXSe27P0bbl1Ooe+XZVh1TAsdtuC01M/KUE3s2imr9CLyMfVcPQ X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA3PR12MB8024 On Mon, May 05, 2025 at 08:44:22AM -0700, Nicolin Chen wrote: > On Mon, May 05, 2025 at 12:01:09PM -0300, Jason Gunthorpe wrote: > > On Mon, Apr 28, 2025 at 10:41:45AM -0700, Nicolin Chen wrote: > > > > I'm uncertain, but perhaps pr_warn_ratelimited() would be a better > > > > alternative to WARN_ON() here? WARN_ON_ONCE() generates warning messages > > > > with kernel call traces in the kernel messages, which might lead users > > > > to believe that something serious has happened in the kernel. > > > > > > We already have similar practice, e.g. iommufd_hwpt_nested_alloc. > > > > > > In my review, a WARN_ON/WARN_ON_ONCE means there is a kernel bug, > > > which shouldn't occur in the first place and isn't something that > > > > Right, so it should never happen from any ioctl path and syzkaller > > should never trigger it based on system call randomization > > > > Is that what this achieves? > > The functions would be still used in the kernel path. So, I think > we need to retain these warnings for that. But given that an ioctl > could trigger a series of WARN_ONs, WARN_ON_ONCE is something that > wouldn't bother user space a lot while it provides the kernel path > enough info to debug. No, it does bother userspace, we must not have ioctl triggerable WARN_ON at all. Jason