From nobody Sat Apr 11 02:17:19 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 6C105C25B0E for ; Tue, 16 Aug 2022 16:37:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236128AbiHPQhn (ORCPT ); Tue, 16 Aug 2022 12:37:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39798 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236516AbiHPQhj (ORCPT ); Tue, 16 Aug 2022 12:37:39 -0400 Received: from mail-ej1-x649.google.com (mail-ej1-x649.google.com [IPv6:2a00:1450:4864:20::649]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CF03980536 for ; Tue, 16 Aug 2022 09:37:37 -0700 (PDT) Received: by mail-ej1-x649.google.com with SMTP id hp22-20020a1709073e1600b007309edc4089so2002325ejc.9 for ; Tue, 16 Aug 2022 09:37:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:mime-version:message-id:date:from:to:cc; bh=Bt86ycU5TqIe5DWAivAOKuWY2/WSOfZm/1Ale3yOGtg=; b=qLBFcuLAhlDwJfDACSf2gt/J+hZ5HtnFVGcb/nrGUjJCkIsoRyLc6pgG87MjjR8KIQ 5Iz1bYpH9D6l6+a2yXEoF1qmbqsfO3LSbDkEQeRvX5ucEx2BqTk5HTxQmnGstdvJ2/Z2 YzWpn4+XRNNACYVTttlB2gPuTIQYUoVVf38GfoZerRGl9jB1RxdEpsDA2NaNBgqtb4Vj BnblFZJWuEkSo0udCHh6tFwqzcPKu6LI4BbFd2cQnQWmcEuRRgSoT6yiJLCOQU55+jP9 aiutqycGzt4DBlwwmbrM9c1zKuDLUCGppvkHPVvSSLp/Pgkw/eKflRRZhpcxWOYy3qMo fFBw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:mime-version:message-id:date:x-gm-message-state :from:to:cc; bh=Bt86ycU5TqIe5DWAivAOKuWY2/WSOfZm/1Ale3yOGtg=; b=dFs2cUankmaN49hcZJyIiKRQogncoMZGKfjp7YRj46XezKtFLW9wnpDfONwoY2CEFT EwNObj1GnvzYxDEopL4j9GtMrwGIm5oTOxXqXB16m2KmJMMzS5usg+0RGDWFQw1VWwow fFC9JSxrEWQbzNgaRsV3HyNOqM+NZLf2reUO0E/0maWwFVO8V37Y5P+FhGpoyKQPQKGV 5zoOeRpeaF2Or33lSh5HA7UXAnPxbRsBiI1YnOlC3ooCmFENGXEJ1Vupp609Jyb99+ZZ 0PugK25OkgifkMFt0a9z70fVDgNLS4edfZ5R+u65uAs1MIa+DIFFcApOMIjczq2VlPcI pdIA== X-Gm-Message-State: ACgBeo0E4eaZnzxtvmxrbwAqnur+LSQ49mF6JeFPgjUSkz3acGRDGW4/ hJnIhcr/kkPhPk9jQadp7pr20u4YuA== X-Google-Smtp-Source: AA6agR7puhx9qSi+R3MTquY9NGN8yzzazt4EdG1n9Sdj8HxHiF3+944McfTa/YkTSASAVUo0d2GXJFjQsg== X-Received: from elver.muc.corp.google.com ([2a00:79e0:9c:201:b8f6:52b8:6a74:6073]) (user=elver job=sendgmr) by 2002:a05:6402:4282:b0:43e:612c:fcf7 with SMTP id g2-20020a056402428200b0043e612cfcf7mr18989740edc.242.1660667856291; Tue, 16 Aug 2022 09:37:36 -0700 (PDT) Date: Tue, 16 Aug 2022 18:36:41 +0200 Message-Id: <20220816163641.2359996-1-elver@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.37.1.595.g718a3a8f04-goog Subject: [PATCH 5.19.y] Revert "mm: kfence: apply kmemleak_ignore_phys on early allocated pool" From: Marco Elver To: elver@google.com, stable@vger.kernel.org, Greg Kroah-Hartman Cc: Alexander Potapenko , Dmitry Vyukov , Andrew Morton , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Will Deacon , Catalin Marinas , Yee Lee , Max Schulze Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" This reverts commit 07313a2b29ed1079eaa7722624544b97b3ead84b. Commit 0c24e061196c21d5 ("mm: kmemleak: add rbtree and store physical address for objects allocated with PA") is not yet in 5.19 (but appears in 6.0). Without 0c24e061196c21d5, kmemleak still stores phys objects and non-phys objects in the same tree, and ignoring (instead of freeing) will cause insertions into the kmemleak object tree by the slab post-alloc hook to conflict with the pool object (see comment). Reports such as the following would appear on boot, and effectively disable kmemleak: | kmemleak: Cannot insert 0xffffff806e24f000 into the object search tree (= overlaps existing) | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.19.0-v8-0815+ #5 | Hardware name: Raspberry Pi Compute Module 4 Rev 1.0 (DT) | Call trace: | dump_backtrace.part.0+0x1dc/0x1ec | show_stack+0x24/0x80 | dump_stack_lvl+0x8c/0xb8 | dump_stack+0x1c/0x38 | create_object.isra.0+0x490/0x4b0 | kmemleak_alloc+0x3c/0x50 | kmem_cache_alloc+0x2f8/0x450 | __proc_create+0x18c/0x400 | proc_create_reg+0x54/0xd0 | proc_create_seq_private+0x94/0x120 | init_mm_internals+0x1d8/0x248 | kernel_init_freeable+0x188/0x388 | kernel_init+0x30/0x150 | ret_from_fork+0x10/0x20 | kmemleak: Kernel memory leak detector disabled | kmemleak: Object 0xffffff806e24d000 (size 2097152): | kmemleak: comm "swapper", pid 0, jiffies 4294892296 | kmemleak: min_count =3D -1 | kmemleak: count =3D 0 | kmemleak: flags =3D 0x5 | kmemleak: checksum =3D 0 | kmemleak: backtrace: | kmemleak_alloc_phys+0x94/0xb0 | memblock_alloc_range_nid+0x1c0/0x20c | memblock_alloc_internal+0x88/0x100 | memblock_alloc_try_nid+0x148/0x1ac | kfence_alloc_pool+0x44/0x6c | mm_init+0x28/0x98 | start_kernel+0x178/0x3e8 | __primary_switched+0xc4/0xcc Reported-by: Max Schulze Signed-off-by: Marco Elver --- mm/kfence/core.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/mm/kfence/core.c b/mm/kfence/core.c index 6aff49f6b79e..4b5e5a3d3a63 100644 --- a/mm/kfence/core.c +++ b/mm/kfence/core.c @@ -603,6 +603,14 @@ static unsigned long kfence_init_pool(void) addr +=3D 2 * PAGE_SIZE; } =20 + /* + * The pool is live and will never be deallocated from this point on. + * Remove the pool object from the kmemleak object tree, as it would + * otherwise overlap with allocations returned by kfence_alloc(), which + * are registered with kmemleak through the slab post-alloc hook. + */ + kmemleak_free(__kfence_pool); + return 0; } =20 @@ -615,16 +623,8 @@ static bool __init kfence_init_pool_early(void) =20 addr =3D kfence_init_pool(); =20 - if (!addr) { - /* - * The pool is live and will never be deallocated from this point on. - * Ignore the pool object from the kmemleak phys object tree, as it would - * otherwise overlap with allocations returned by kfence_alloc(), which - * are registered with kmemleak through the slab post-alloc hook. - */ - kmemleak_ignore_phys(__pa(__kfence_pool)); + if (!addr) return true; - } =20 /* * Only release unprotected pages, and do not try to go back and change --=20 2.37.1.595.g718a3a8f04-goog