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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: OMN/jANpJsShqS2+jv0/n5quoDQXwdnc5/6NzNqcFxQYTudqwFNZKWR+rDap6r/nJFrZlEa3XRxTsQDtuCUZP/jtUYn5xO3ewzYbNNQWjikWExLsGQB8Hg8J3nFEap0FTknwUpNBVJFhR9M6IKalEa2v+kuFl4KJVDkfW1IXgQsss2buV+ug9GhviGGsXyylbs/+gEziEjSsgSlKm7eBvBQDwNK5CGd9QGtT2oD2HoE6SJmfk8CHc2KS3HdXnPmR108YZ4Hhwe0iA7cIJnbuygkl/PAvS18eIV8N2zm+CG4i4HNJg2JMuFTQcZH5IQf7ghQBZ6doCMpX/YpSKxkz+HYrHAr1nSSahR8WLbSdyu8S/w4p736rjO+rO2IqS5BAi1nMpRxEeupT/ncAbM5j/mu9HSxRuJaaX6Mljhf2an8NVi0XuYHeuTw9wenZOh1p X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Mar 2026 15:50:08.1122 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 7d2c0594-4f2a-4539-f1af-08de8e7404d5 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb08.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CH2PEPF0000009B.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR12MB6793 Hello Peter, On 3/30/2026 8:10 PM, Peter Zijlstra wrote: > On Mon, Mar 30, 2026 at 08:07:06PM +0530, K Prateek Nayak wrote: >> Hello Peter, >> >> On 3/30/2026 3:40 PM, Peter Zijlstra wrote: >>> This means, that if the two tasks playing leapfrog can reach the >>> critical speed to reach the overflow point inside one tick's worth of >>> time, we're up a creek. >>> >>> If this is indeed the case, then the below should cure things. >> >> I have been running with this for four hours now and haven't seen >> any splats or crashes on my setup. I could reliably trigger the >> warning from __sum_w_vruntime_add() within an hour previously so >> it is safe to say I was hitting exactly this. >> >> Feel free to include: >> >> Tested-by: K Prateek Nayak > > Ha!, excellent. Thanks! Turns out I spoke too soon and it did eventually run into that problem again and then eventually crashed in pick_task_fair() later so there is definitely something amiss still :-( I'll throw in some debug traces and get back tomorrow. -- Thanks and Regards, Prateek