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charset=utf-8 Content-Disposition: inline In-Reply-To: <1574166203-151975-2-git-send-email-alex.shi@linux.alibaba.com> User-Agent: Mutt/1.12.2 (2019-09-21) Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Nov 19, 2019 at 08:23:15PM +0800, Alex Shi wrote: > ../mm/swap.c: In function =E2=80=98__page_cache_release=E2=80=99: > ../mm/swap.c:67:10: warning: =E2=80=98flags=E2=80=99 may be used unin= itialized in this > function [-Wmaybe-uninitialized] > lruvec =3D lock_page_lruvec_irqsave(page, pgdat, flags); > ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ At this point in the series, there is no lock_page_lruvec_irqsave() yet, so this patch is out of order. Please don't do that. It's very hard to review patches that depend on later changes to make sense. > Signed-off-by: Alex Shi > Cc: Andrew Morton > Cc: linux-mm@kvack.org > Cc: linux-kernel@vger.kernel.org > --- > mm/swap.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) >=20 > diff --git a/mm/swap.c b/mm/swap.c > index 5341ae93861f..c36a10244d07 100644 > --- a/mm/swap.c > +++ b/mm/swap.c > @@ -62,7 +62,7 @@ static void __page_cache_release(struct page *page) > if (PageLRU(page)) { > pg_data_t *pgdat =3D page_pgdat(page); > struct lruvec *lruvec; > - unsigned long flags; > + unsigned long flags =3D 0; Use unintialized_var() for these cases to make the intent clear.