I don't know why dst->i_lock is affected by src->i_size_seqcount.
Do you mean that your test issued write(2) to the lower/actual file so
frequently that i_size_read() in unionfs always failed?
Is your test
iogen01 export LTPROOT; rwtest -N iogen01 -i 120s -s read,write -Da -Dv -n 2 500b:doio.f1.$$ 1000b:doio.f2.$$
line in runtest/fs?
Junjiro Okajima
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