On Mon, Dec 7, 2020 at 2:16 AM Michal Kubecek <mkubecek@xxxxxxx> wrote: > > On Thu, Nov 12, 2020 at 08:18:57AM +0800, Alex Shi wrote: > > > > > > 在 2020/11/11 上午3:50, Andrew Morton 写道: > > > On Tue, 10 Nov 2020 08:39:24 +0530 Souptick Joarder <jrdr.linux@xxxxxxxxx> wrote: > > > > > >> On Fri, Nov 6, 2020 at 4:55 PM Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> wrote: > > >>> > > >>> Otherwise it cause gcc warning: > > >>> ^~~~~~~~~~~~~~~ > > >>> ../mm/filemap.c:830:14: warning: no previous prototype for > > >>> ‘__add_to_page_cache_locked’ [-Wmissing-prototypes] > > >>> noinline int __add_to_page_cache_locked(struct page *page, > > >>> ^~~~~~~~~~~~~~~~~~~~~~~~~~ > > >> > > >> Is CONFIG_DEBUG_INFO_BTF enabled in your .config ? > > > > > > hm, yes. > > > > When the config enabled, compiling looks good untill pahole tool > > used to get BTF info, but I still failed on a right version pahole > > > 1.16. Sorry. > > > > > > > >>> > > >>> Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> > > >>> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > >>> Cc: linux-mm@xxxxxxxxx > > >>> Cc: linux-kernel@xxxxxxxxxxxxxxx > > >>> --- > > >>> mm/filemap.c | 2 +- > > >>> 1 file changed, 1 insertion(+), 1 deletion(-) > > >>> > > >>> diff --git a/mm/filemap.c b/mm/filemap.c > > >>> index d90614f501da..249cf489f5df 100644 > > >>> --- a/mm/filemap.c > > >>> +++ b/mm/filemap.c > > >>> @@ -827,7 +827,7 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask) > > >>> } > > >>> EXPORT_SYMBOL_GPL(replace_page_cache_page); > > >>> > > >>> -noinline int __add_to_page_cache_locked(struct page *page, > > >>> +static noinline int __add_to_page_cache_locked(struct page *page, > > >>> struct address_space *mapping, > > >>> pgoff_t offset, gfp_t gfp, > > >>> void **shadowp) > > > > > > It's unclear to me whether BTF_ID() requires that the target symbol be > > > non-static. It doesn't actually reference the symbol: > > > > > > #define BTF_ID(prefix, name) \ > > > __BTF_ID(__ID(__BTF_ID__##prefix##__##name##__)) > > > > > > > The above usage make me thought BTF don't require the symbol, though > > the symbol still exist in vmlinux with 'static'. > > > > So any comments of this, Alexei? > > It's probably more complicated: our v5.10-rc7 builds with > CONFIG_DEBUG_INFO_BTF=y fail on ppc64 and ppc64le with > > BTFIDS vmlinux > FAILED unresolved symbol __add_to_page_cache_locked > > > but succeed on x86_64, i586, aarch64 and s390x. So far I don't see why > this should depend on architecture. > Fedora is failing with rc7 on the same issue on PPC only. Justin
