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The first > patch of this series adds the regression test case for the fix. > > After the kernel commit, writes to the file queue/scheduler can return > -EBUSY. This is rare but can happen when udevd writes to the file at > exactly the same timing as blktests test cases, and it results in > unexpected test failures. The other two patches in this series handle > -EBUSY and avoid the failures. > > [1] https://lore.kernel.org/linux-block/20260626004221.711326-1-shinichiro.kawasaki@wdc.com/ > > Shin'ichiro Kawasaki (3): > block: add test for concurrent IO scheduler switching > check: introduce _write_queue_sched() to repeat queue/scheduler writes > common, block/{015,020,021,027,040}, zbd/012: use _write_queue_sched() FYI, I applied the series. As to the first patch, I renumbered the test case from block/045 to block/047.