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How is >> ->lock() with F_SETLKW called? > > I got your point finally, > yes, you are right, now this cannot happen. > However I'm going to fix all affected filesystems and then revert > "ksmbd: force "fail immediately" flag on fs with its own ->lock" > When this happen and ksmbd will still use IS_SETLKW it will trigger the problems described below. I've created https://bugzilla.kernel.org/show_bug.cgi?id=215383