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charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: oneplus.com X-MS-Exchange-CrossTenant-Network-Message-Id: 362dd64b-3dc8-49aa-f190-08d6901ffb37 X-MS-Exchange-CrossTenant-originalarrivaltime: 11 Feb 2019 12:53:53.8857 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-id: 0423909d-296c-463e-ab5c-e5853a518df8 X-MS-Exchange-Transport-CrossTenantHeadersStamped: SL2PR04MB3081 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some of the page flags, like PG_locked is not supposed to be set twice. Currently, there is no protection around this and many callers directly tries to set this bit. Others follow trylock_page() which is much safer version of the same. But, for performance issues, we may not want to implement wait-until-set. So, at least, find out who is doing double setting and fix them. Change-Id: I1295fcb8527ce4b54d5d11c11287fc7516006cf0 Signed-off-by: Chintan Pandya --- include/linux/page-flags.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index a56a9bd4bc6b..e307775c2b4a 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -208,7 +208,7 @@ static __always_inline int Page##uname(struct page *pag= e) \ =20 #define SETPAGEFLAG(uname, lname, policy) \ static __always_inline void SetPage##uname(struct page *page) \ - { set_bit(PG_##lname, &policy(page, 1)->flags); } + { WARN_ON(test_and_set_bit(PG_##lname, &policy(page, 1)->flags)); } =20 #define CLEARPAGEFLAG(uname, lname, policy) \ static __always_inline void ClearPage##uname(struct page *page) \ --=20 2.17.1