Erroneous VM_MINOR_FAULT return from filemap_fault?

Erroneous VM_MINOR_FAULT return from filemap_fault?

[Steven Walter]

There appears to be a path through filemap_fault such that the function
returns VM_MINOR_FAULT, even though disk IO was performed.  Suppose that
the page in question is not already in the page cache (find_lock_page
returns NULL) and we trip the MMAP_LOTSAMISS logic, ending up at
no_cached_page.  Immediately page_cache_read is called, but ret was
never set to VM_MAJOR_FAULT (still at the default of VM_MINOR_FAULT).
Control jumps back to retry_find, find_lock_page returns the page, and
eventually the function returns VM_MINOR_FAULT.

Is there some assumption I'm missing where the execution path I
summarized couldn't actually happen?  Perhaps this behavior is
intentional?  Certainly it seems that if IO is performed, the fault
should be considered a major fault.
-- 
-Steven Walter <stevenrwalter@gmail.com>
Freedom is the freedom to say that 2 + 2 = 4
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