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>> >> >> >> I would expect that this would fire already if there is still a page >> >> referenced. >> >> >> >> Are you running with CONFIG_DEBUG_VM=3Dy ? >> >> >> >> >> >> -- >> >> Cheers, >> >> >> >> David > > Thinking again without my computer at hand =E2=80=A6 isn=E2=80=98t the ca= ll completely optimized out without CONFIG_DEBUG_VM? > > > > At least that=E2=80=99s what I remember. Right. Without CONFIG_DEBUG_VM=3Dy, VM_WARN_ON(!put_page_testzero(pfn_to_pa= ge(pfn))) and is_check_pages_enabled(), which leads to free_page_is_bad()=E2=80=99s =E2=80=9Cpage dumped because: nonzero _refcount=E2=80=9D, are disabled. It seems to me that someone else bump the page refcount between VM_WARN_ON(!put_page_testzero(pfn_to_page(pfn))) and free_page_is_bad(). Best Regards, Yan, Zi