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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?0GG49o3z71UHuw+f2WYy0tQtHnmFNvTTBpkCr5+dnlHmihMZ6JjYj7wrpTkg?= =?us-ascii?Q?jMuGx8Xjrxk3vlMKuZ7UHVr6xp6pPKarznRzGsd9i/vD9o1EFUzdmQMpkHGB?= =?us-ascii?Q?e0V+JHXvcPLNDPBMRe/F4IlH8k1MjgBzmaJOLLOAozryI+m1PCrEQVcg8Zo/?= =?us-ascii?Q?SKJuztU3k4ReEsveo1GqCMSQtruPMFfZpqlv2a8wdZ595Zkgq/euqnEe9gLC?= =?us-ascii?Q?PXmwnWjE3eSFrEwPybuvokicJ5OElc162MbocF20DnHPADRKL74H+AH3DJCg?= =?us-ascii?Q?usRtOYs+UclwJUBH5dZChDP+8G8w8GvKKiZ5oPXIRwc+0r5rvV2+wdvyceWB?= =?us-ascii?Q?3/XRoLqv8Sf6PvmEyD5GDQt/xs3whap2OL6ksvdyLHj911Kb0kokx7K6hv8Y?= =?us-ascii?Q?RkF2zF/R0uzzY5PRLPV1tNEZxL3jvjcaJsbPK3qUxGw61uHQW9MmabTTD50r?= =?us-ascii?Q?odnOPl6qU6U5erqFAsU034WIZXGs0eKbrTs6L75jDx2wHAmRhjXWI2PKl0N2?= =?us-ascii?Q?entHR2WXmVIHJZYoagskpplWPVZIERj5Y2YYn/pUGrTBIGz0hn+imq0VpPxG?= =?us-ascii?Q?HXYILMwiFUhddPAXdCbTaxjMatMmlNJQCPfq08Uc2tKYGFP03kPMkgz4GGRO?= =?us-ascii?Q?vKNUVe/L9a5WlEg/tYr9iDpvXjHakeokZSEf6OTgAywOz4Za9336xo65NQnS?= =?us-ascii?Q?brui6iJR3AasT3tlvFwxdF6d0b8REmPsUv+EGVeM/E0H4o7C0BpBanQXtww+?= =?us-ascii?Q?ppMhzNzek0yhu0QtpXBJtpFL+SvUhdx4o9PwoQbsn/MF2HT/2r+dzgC711+2?= =?us-ascii?Q?kMWzF3dTCatetFuFoIP1Gk5j521Dj6BFqQ51b3p44p6BbY7qlWni/N2Pvw0C?= =?us-ascii?Q?NWMBQQ7+p/xfhRkDGuwmZhuGadDpqE6RHiacdb+/qq5y0DxNZO1g1aMM+JBB?= =?us-ascii?Q?17OkqMWOwX9HgrUj1GdfRL2EiabetdiwYuZT49kbpqqSWaKKnJEmtiBnAVLY?= =?us-ascii?Q?khDxNvFIRUsT6JCWG4HWAsfnYrAkU5hd/NZjgRv1wTkZNa+3i8WkxO5nTReC?= =?us-ascii?Q?qsU/jPvXCv4Bnx3BJEvpwgKzJC2LreFavWVdx7816vpX3fnlRDZE5M3igKzq?= =?us-ascii?Q?NIKlAol3hZ4sXC6a/y/MRUfXK7qxT2hoTLYx+TsWmJBvA7zupC+yO4yXcZtq?= =?us-ascii?Q?bey5UNOAzm5RWLFdHTSIdm9pbwabD8P0LubZj1fTZqtx//Jb3HKuV3d+wjeS?= =?us-ascii?Q?h9ngCSEcnoyhYBPOptLsxM5TjNkIsAVa3FWo4lFFORDw4TW8wYPGx8Ho7vrO?= =?us-ascii?Q?YX7lKtsb3TzxrPgT3hv7GNpZb2HBt4HfE/F0b9vCZN8QgQjyqslV82Ibl84q?= =?us-ascii?Q?ihfCpPZiX7IKbYZsIgQxoyqMk4uNFGeOtGZDOcb1GoWNavRmKB4O0zPg0PU3?= =?us-ascii?Q?hDTkTXs3Sj/MKOoGebwJMhZgLHFotzGkuAYcMj3zkw0DDGyVkUlW8YQnHB15?= =?us-ascii?Q?zuMuBXRcpIIVT5P0oeiLQzeN8MHEOczYWhr0qRMMLixzdg0XnDkUpFaP56jA?= =?us-ascii?Q?Kejn3aK9SZRsiYRh9EBvvmfyUWP8Nhm8i6GenjfH?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 74b61a55-510f-46eb-d490-08dd769f10d0 X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Apr 2025 13:12:51.4070 (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: T1q2JnDPaS8I22BkgGKX9z60MS77LaEALVyyAQ+25eAWGDCVE7Dx/tfmBr0iStY5lmEZGyP0qO/L+sJRHuR7Xg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV2PR12MB5893 On Tue, Apr 08, 2025 at 05:17:16AM -0700, Breno Leitao wrote: > Hello Andrea, > > On Tue, Apr 08, 2025 at 01:30:32PM +0200, Andrea Righi wrote: > > Hi Breno, > > > > I already acked even the buggy version, so this one looks good. :) > > > > On Tue, Apr 08, 2025 at 04:09:02AM -0700, Breno Leitao wrote: > > > Replace kzalloc with kvzalloc for the exit_dump buffer allocation, which > > > can require large contiguous memory (up to order=9) depending on the > > > > BTW, from where this order=9 is coming from? exit_dump_len is 32K by > > default, but a BPF scheduler can arbitrarily set it to any value via > > ops->exit_dump_len, so it could be even bigger than an order 9 allocation. > > You are absolutely correct, this allocation could be of any size. > > I've got this problem because I was monitoring the Meta fleet, and saw > a bunch of allocation failures and decided to investigate. In this case > specifically, the users were using order=9 (512 pages), but, again, this > could be even bigger. I see, makes sense. Maybe we can rephrase this part to not mention the order=9 allocation and avoid potential confusion. Thanks, -Andrea