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That leads to triggering the hung task detector when we wait on io-wq workers to exit. I did queue a patch for 6.19 that makes this less likely to occur, as it'll only run the very first of the items before noticing the cancelation: https://lore.kernel.org/io-uring/937c3e38-368e-43eb-9d7e-2dcc0697799f@kernel.dk/ but even that isn't quite enough due to how much syzbot overloads the system. This will still throw a WARN_ON_ONCE(), which perhaps should just be a printk() of some sort as the trace isn't THAT interesting. But it will avoid hitting the hung task timeout detector, which for syzbot leads to a panic + reboot. io_uring/io-wq.c | 22 +++++++++++++++++++++- io_uring/io_uring.c | 2 +- io_uring/io_uring.h | 6 ++++++ 3 files changed, 28 insertions(+), 2 deletions(-) -- Jens Axboe