FWIW, it is documented in mount(8):
log (FFS only) Mount the file system with wapbl(4) meta-
data journaling, also known simply as logging. It
provides rapid metadata updates and eliminates the
need to check file system consistency after a system
outage. A file system mounted with log can not be
mounted with async. [...]
Well, my bad :(
Wouldn't it be wise that mount(8) forbids the use of both flags ?
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Emile `iMil' Heitor .°. <imil@{home.imil.net,NetBSD.org,gcu.info}>
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