From nobody Tue Apr 7 16:32:14 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC653ECAAD2 for ; Fri, 26 Aug 2022 06:43:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245059AbiHZGnZ (ORCPT ); Fri, 26 Aug 2022 02:43:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42498 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238943AbiHZGnX (ORCPT ); Fri, 26 Aug 2022 02:43:23 -0400 Received: from SHSQR01.spreadtrum.com (mx1.unisoc.com [222.66.158.135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BB499D1271 for ; Thu, 25 Aug 2022 23:43:20 -0700 (PDT) Received: from SHSend.spreadtrum.com (bjmbx01.spreadtrum.com [10.0.64.7]) by SHSQR01.spreadtrum.com with ESMTPS id 27Q6f85Y006348 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NO); Fri, 26 Aug 2022 14:41:08 +0800 (CST) (envelope-from zhaoyang.huang@unisoc.com) Received: from bj03382pcu.spreadtrum.com (10.0.74.65) by BJMBX01.spreadtrum.com (10.0.64.7) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Fri, 26 Aug 2022 14:41:08 +0800 From: "zhaoyang.huang" To: Andrew Morton , Catalin Marinas , Zhaoyang Huang , , , Subject: [RFC PATCH] mm: introduce __GFP_TRACKLEAK to track in-kernel allocation Date: Fri, 26 Aug 2022 14:40:48 +0800 Message-ID: <1661496048-26410-1-git-send-email-zhaoyang.huang@unisoc.com> X-Mailer: git-send-email 1.9.1 MIME-Version: 1.0 X-Originating-IP: [10.0.74.65] X-ClientProxiedBy: SHCAS03.spreadtrum.com (10.0.1.207) To BJMBX01.spreadtrum.com (10.0.64.7) X-MAIL: SHSQR01.spreadtrum.com 27Q6f85Y006348 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Zhaoyang Huang Kthread and drivers could fetch memory via alloc_pages directly which make = them hard to debug when leaking. Solve this by introducing __GFP_TRACELEAK and r= euse kmemleak mechanism which unified most of kernel cosuming pages into kmemlea= k. Signed-off-by: Zhaoyang Huang --- include/linux/gfp.h | 4 +++- include/linux/page-flags.h | 3 +++ mm/kmemleak.c | 2 +- mm/page_alloc.c | 6 ++++++ 4 files changed, 13 insertions(+), 2 deletions(-) diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 2d2ccae..081ab54 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -68,6 +68,7 @@ #else #define ___GFP_NOLOCKDEP 0 #endif +#define ___GFP_TRACKLEAK 0x10000000u /* If the above are modified, __GFP_BITS_SHIFT may need updating */ =20 /* @@ -259,12 +260,13 @@ #define __GFP_SKIP_ZERO ((__force gfp_t)___GFP_SKIP_ZERO) #define __GFP_SKIP_KASAN_UNPOISON ((__force gfp_t)___GFP_SKIP_KASAN_UNPOIS= ON) #define __GFP_SKIP_KASAN_POISON ((__force gfp_t)___GFP_SKIP_KASAN_POISON) +#define __GFP_TRACKLEAK ((__force gfp_t)___GFP_TRACKLEAK) =20 /* Disable lockdep for GFP context tracking */ #define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP) =20 /* Room for N __GFP_FOO bits */ -#define __GFP_BITS_SHIFT (27 + IS_ENABLED(CONFIG_LOCKDEP)) +#define __GFP_BITS_SHIFT (28 + IS_ENABLED(CONFIG_LOCKDEP)) #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1)) =20 /** diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index e66f7aa..ef0f814 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -942,6 +942,7 @@ static inline bool is_page_hwpoison(struct page *page) #define PG_offline 0x00000100 #define PG_table 0x00000200 #define PG_guard 0x00000400 +#define PG_trackleak 0x00000800 =20 #define PageType(page, flag) \ ((page->page_type & (PAGE_TYPE_BASE | flag)) =3D=3D PAGE_TYPE_BASE) @@ -1012,6 +1013,8 @@ static inline int page_has_type(struct page *page) */ PAGE_TYPE_OPS(Guard, guard) =20 +PAGE_TYPE_OPS(Trackleak, trackleak) + extern bool is_free_buddy_page(struct page *page); =20 PAGEFLAG(Isolated, isolated, PF_ANY); diff --git a/mm/kmemleak.c b/mm/kmemleak.c index 422f28f..a182f5d 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -1471,7 +1471,7 @@ static void kmemleak_scan(void) if (page_zone(page) !=3D zone) continue; /* only scan if page is in use */ - if (page_count(page) =3D=3D 0 || PageReserved(page)) + if (page_count(page) =3D=3D 0) continue; scan_block(page, page + 1, NULL); if (!(pfn & 63)) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e008a3d..d8995c6 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1361,6 +1361,8 @@ static __always_inline bool free_pages_prepare(struct= page *page, page->mapping =3D NULL; if (memcg_kmem_enabled() && PageMemcgKmem(page)) __memcg_kmem_uncharge_page(page, order); + if (PageTrackleak(page)) + kmemleak_free(page); if (check_free) bad +=3D check_free_page(page); if (bad) @@ -5444,6 +5446,10 @@ struct page *__alloc_pages(gfp_t gfp, unsigned int o= rder, int preferred_nid, __free_pages(page, order); page =3D NULL; } + if (gfp & __GFP_TRACKLEAK) { + kmemleak_alloc(page_address(page), PAGE_SIZE << order, 1, gfp & ~__GFP_T= RACKLEAK); + __SetPageTrackleak(page); + } =20 trace_mm_page_alloc(page, order, alloc_gfp, ac.migratetype); =20 --=20 1.9.1