From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4CD24CA9EB9 for ; Tue, 29 Oct 2019 04:21:31 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 028182087E for ; Tue, 29 Oct 2019 04:21:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=axtens.net header.i=@axtens.net header.b="q37hvvFE" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 028182087E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=axtens.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A535F6B000E; Tue, 29 Oct 2019 00:21:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A03CB6B0010; Tue, 29 Oct 2019 00:21:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8CB2A6B0266; Tue, 29 Oct 2019 00:21:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0231.hostedemail.com [216.40.44.231]) by kanga.kvack.org (Postfix) with ESMTP id 6708E6B000E for ; Tue, 29 Oct 2019 00:21:30 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id F0F00181AEF3F for ; Tue, 29 Oct 2019 04:21:29 +0000 (UTC) X-FDA: 76095523098.03.fish34_817042d30c815 X-HE-Tag: fish34_817042d30c815 X-Filterd-Recvd-Size: 5531 Received: from mail-pf1-f196.google.com (mail-pf1-f196.google.com [209.85.210.196]) by imf26.hostedemail.com (Postfix) with ESMTP for ; Tue, 29 Oct 2019 04:21:29 +0000 (UTC) Received: by mail-pf1-f196.google.com with SMTP id v19so8588585pfm.3 for ; Mon, 28 Oct 2019 21:21:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=axtens.net; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=E6G/cbdwI55VRIDPH2MzPtSSwLNnlVDKj+xUqyB9XvU=; b=q37hvvFEaBAuDhdw8f9RGZPAKbEe6zMTpH1vieG+zpL2j/QDs8RghoIx9JE+q4QWze TAruY1QMB+c1d5affF47SiBVcB02uLSf31ZZ6pl18sMLuLqjyMUqrZhipq3ZGdu16JlP nJAdQq+06ElZPTzvTwKeK7V2Y0q4KaKOeZi5s= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=E6G/cbdwI55VRIDPH2MzPtSSwLNnlVDKj+xUqyB9XvU=; b=UUQJ4IkHWTOQVyD/sor/zniHf82/pTYZ6iOSUyzGTQHIeZyCcbVgmrmJ88HpkPb1d4 judtN1C4ruZPVYqHomdni/PzF/SKqfJkgcAYOKh0mBiMlXfidQqwVAEzSuO/629lY70P GemjlNdCEHSwzPCg+GGNBra4CSXM/1uCxbK/4tpdZVFCJS1KUVlu7XrCHozG4DlnsTaX fANH9vFc7Ey3ONU5bv69dZ4ZH19WbFb2kj0yougHnhwTXuZ9R+IPb6Qdehno2iERI2eT a5OoqtuABlG3seGM9BQvEZYJPuy0jo+u5hm6cQBI0Nf5HF1pxT0jFH5UJ3nPrNiC180H 9Pgg== X-Gm-Message-State: APjAAAWo8JGUf5ojDeIhQhzRCqPCnz4TsJtlI9loHOLdNYCO5b8JXEih P8lUGGhU1Y8A5jwZILiXSJTAMQ== X-Google-Smtp-Source: APXvYqxNDS1dIEPkNBGrfTraoXwMKGGsjqxNiWzOEOkJlq5Mx5SitV2hc6VnXEFqIfQN/nkn2AOfVQ== X-Received: by 2002:a63:e60b:: with SMTP id g11mr23118732pgh.119.1572322888371; Mon, 28 Oct 2019 21:21:28 -0700 (PDT) Received: from localhost ([2001:44b8:802:1120:783a:2bb9:f7cb:7c3c]) by smtp.gmail.com with ESMTPSA id z4sm957607pjt.20.2019.10.28.21.21.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 28 Oct 2019 21:21:27 -0700 (PDT) From: Daniel Axtens To: kasan-dev@googlegroups.com, linux-mm@kvack.org, x86@kernel.org, aryabinin@virtuozzo.com, glider@google.com, luto@kernel.org, linux-kernel@vger.kernel.org, mark.rutland@arm.com, dvyukov@google.com, christophe.leroy@c-s.fr Cc: linuxppc-dev@lists.ozlabs.org, gor@linux.ibm.com, Daniel Axtens Subject: [PATCH v10 5/5] kasan debug: track pages allocated for vmalloc shadow Date: Tue, 29 Oct 2019 15:20:59 +1100 Message-Id: <20191029042059.28541-6-dja@axtens.net> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191029042059.28541-1-dja@axtens.net> References: <20191029042059.28541-1-dja@axtens.net> MIME-Version: 1.0 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: Provide the current number of vmalloc shadow pages in /sys/kernel/debug/kasan/vmalloc_shadow_pages. Signed-off-by: Daniel Axtens --- v10: rebase on linux-next/master. v8: rename kasan_vmalloc/shadow_pages -> kasan/vmalloc_shadow_pages On v4 (no dynamic freeing), I saw the following approximate figures on my test VM: - fresh boot: 720 - after test_vmalloc: ~14000 With v5 (lazy dynamic freeing): - boot: ~490-500 - running modprobe test_vmalloc pushes the figures up to sometimes as high as ~14000, but they drop down to ~560 after the test ends. I'm not sure where the extra sixty pages are from, but running the test repeately doesn't cause the number to keep growing, so I don't think we're leaking. - with vmap_stack, spawning tasks pushes the figure up to ~4200, then some clearing kicks in and drops it down to previous levels again. --- mm/kasan/common.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 6e7bc5d3fa83..a4b5c64da16f 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -35,6 +35,7 @@ #include #include #include +#include =20 #include =20 @@ -750,6 +751,8 @@ core_initcall(kasan_memhotplug_init); #endif =20 #ifdef CONFIG_KASAN_VMALLOC +static u64 vmalloc_shadow_pages; + static int kasan_populate_vmalloc_pte(pte_t *ptep, unsigned long addr, void *unused) { @@ -770,6 +773,7 @@ static int kasan_populate_vmalloc_pte(pte_t *ptep, un= signed long addr, if (likely(pte_none(*ptep))) { set_pte_at(&init_mm, addr, ptep, pte); page =3D 0; + vmalloc_shadow_pages++; } spin_unlock(&init_mm.page_table_lock); if (page) @@ -858,6 +862,7 @@ static int kasan_depopulate_vmalloc_pte(pte_t *ptep, = unsigned long addr, if (likely(!pte_none(*ptep))) { pte_clear(&init_mm, addr, ptep); free_page(page); + vmalloc_shadow_pages--; } spin_unlock(&init_mm.page_table_lock); =20 @@ -974,4 +979,22 @@ void kasan_release_vmalloc(unsigned long start, unsi= gned long end, (unsigned long)shadow_end); } } + +static __init int kasan_init_debugfs(void) +{ + struct dentry *root; + + root =3D debugfs_create_dir("kasan", NULL); + if (IS_ERR(root)) { + if (PTR_ERR(root) =3D=3D -ENODEV) + return 0; + return PTR_ERR(root); + } + + debugfs_create_u64("vmalloc_shadow_pages", 0444, root, + &vmalloc_shadow_pages); + + return 0; +} +late_initcall(kasan_init_debugfs); #endif --=20 2.20.1