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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 711D5C433EF for ; Thu, 2 Dec 2021 15:33:11 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E97386B0072; Thu, 2 Dec 2021 10:33:00 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E1E466B0073; Thu, 2 Dec 2021 10:33:00 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CC0026B0074; Thu, 2 Dec 2021 10:33:00 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0222.hostedemail.com [216.40.44.222]) by kanga.kvack.org (Postfix) with ESMTP id B690F6B0072 for ; Thu, 2 Dec 2021 10:33:00 -0500 (EST) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 731D48B313 for ; Thu, 2 Dec 2021 15:32:50 +0000 (UTC) X-FDA: 78873246900.26.48091BC Received: from mail-qt1-f174.google.com (mail-qt1-f174.google.com [209.85.160.174]) by imf28.hostedemail.com (Postfix) with ESMTP id 191D190000A1 for ; Thu, 2 Dec 2021 15:32:49 +0000 (UTC) Received: by mail-qt1-f174.google.com with SMTP id o17so92321qtk.1 for ; Thu, 02 Dec 2021 07:32:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=evmGFi4x3OMEuAhoToZgbOGTd3Zzv0LAm/HoRCUBdXY=; b=dnoa81zGRMKX+fxgR59mxyYQdxdpV6Qj1lFXnDFyeJ3d1kJcXt1fJv+8OVT5vOB+P7 dr5L7dJ/iKrcNwJrsvsHrk1BmjWE1g0DPb5Ris9uf/vvDcmbfIpefH8STyaPDbP0bPNT KZMxKP3nuw1Im+kS9zQkLV+XDvWSLtVcb5Gg13ALxW98jnUILNesY17smnjq7CF4oPiD jBq3K+vgx5jVRdo+iVjbmGw8wcZpIPaofJvqhkHO8Ngw4xpBzDgxYA2F6mmVSheVg1I7 H/vClpYyvHGDh3FYRoTFPsP+k/WDtvjh7OKadojpMhwySoxYPb/2eG03TzlHQcFyb1ah Xm7g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=evmGFi4x3OMEuAhoToZgbOGTd3Zzv0LAm/HoRCUBdXY=; b=qkmggtV21mnovA2gqOrCJV+Qir/y7ZSOD0t6xeJ+GllYXm52/N7lxQHJHzuN6PFaS/ tgC5l6qZ2fy7tZJR4lrKOi8TkQKL5cdLOIwxoA8NPilVORDd+O+txgddOeEqfSNTTrDT Itm4Pd2cQe4RZ5P+saTuUWuWsuAmhwhIz3S35ojcdDE/S1c2onzQpKDVen65P6ZeGF4o ExKTJKP/HU4huG8TaMadSlXhCJvEtuNYN8N/UX/xKupzoXjZ5cVvze7dPSKhILVS/E+D 5hP3jZQisaJSyEinOXkY7vjDz2fOXhJrtrKXD6Irh+1igTmu9sbmYjcHQup6SXYeaTQi xe9Q== X-Gm-Message-State: AOAM533XOb0XnxvUUCwdb8H6VIDP1A8Nc2WaInDO5gJJVyj6Wf6DONUK n+AKh7OBukxYkUuy4sWekR4Gk/wf8bSy24+58o2O8Q== X-Google-Smtp-Source: ABdhPJxz3J2eijtJeTTJv1U94XJcpSfqGPlThSRton8V221yobaPgqr5L2B0Y28tNd/+wr09cEmnlOziw+BbN1/bEhQ= X-Received: by 2002:ac8:7fc5:: with SMTP id b5mr14623476qtk.492.1638459169188; Thu, 02 Dec 2021 07:32:49 -0800 (PST) MIME-Version: 1.0 References: <64f8b74a4766f886a6df77438e7e098205fd0863.1638308023.git.andreyknvl@google.com> In-Reply-To: <64f8b74a4766f886a6df77438e7e098205fd0863.1638308023.git.andreyknvl@google.com> From: Alexander Potapenko Date: Thu, 2 Dec 2021 16:32:12 +0100 Message-ID: Subject: Re: [PATCH 03/31] kasan, page_alloc: merge kasan_free_pages into free_pages_prepare To: andrey.konovalov@linux.dev Cc: Marco Elver , Vincenzo Frascino , Catalin Marinas , Peter Collingbourne , Andrey Konovalov , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, Andrew Morton , linux-mm@kvack.org, Will Deacon , linux-arm-kernel@lists.infradead.org, Evgenii Stepanov , linux-kernel@vger.kernel.org, Andrey Konovalov Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 191D190000A1 X-Stat-Signature: gcdmkrd7de6p7ca1kygrrzdbduqmdssx Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=dnoa81zG; spf=pass (imf28.hostedemail.com: domain of glider@google.com designates 209.85.160.174 as permitted sender) smtp.mailfrom=glider@google.com; dmarc=pass (policy=reject) header.from=google.com X-HE-Tag: 1638459169-255761 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 30, 2021 at 10:40 PM wrote: > > From: Andrey Konovalov > > Currently, the code responsible for initializing and poisoning memory > in free_pages_prepare() is scattered across two locations: > kasan_free_pages() for HW_TAGS KASAN and free_pages_prepare() itself. > This is confusing. > > This and a few following patches combine the code from these two > locations. Along the way, these patches also simplify the performed > checks to make them easier to follow. > > This patch replaces the only caller of kasan_free_pages() with its > implementation. > > As kasan_has_integrated_init() is only true when CONFIG_KASAN_HW_TAGS > is enabled, moving the code does no functional changes. > > This patch is not useful by itself but makes the simplifications in > the following patches easier to follow. > > Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko > --- > include/linux/kasan.h | 8 -------- > mm/kasan/common.c | 2 +- > mm/kasan/hw_tags.c | 11 ----------- > mm/page_alloc.c | 6 ++++-- > 4 files changed, 5 insertions(+), 22 deletions(-) > > diff --git a/include/linux/kasan.h b/include/linux/kasan.h > index d8783b682669..89a43d8ae4fe 100644 > --- a/include/linux/kasan.h > +++ b/include/linux/kasan.h > @@ -95,7 +95,6 @@ static inline bool kasan_hw_tags_enabled(void) > } > > void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flag= s); > -void kasan_free_pages(struct page *page, unsigned int order); > > #else /* CONFIG_KASAN_HW_TAGS */ > > @@ -116,13 +115,6 @@ static __always_inline void kasan_alloc_pages(struct= page *page, > BUILD_BUG(); > } > > -static __always_inline void kasan_free_pages(struct page *page, > - unsigned int order) > -{ > - /* Only available for integrated init. */ > - BUILD_BUG(); > -} > - > #endif /* CONFIG_KASAN_HW_TAGS */ > > static inline bool kasan_has_integrated_init(void) > diff --git a/mm/kasan/common.c b/mm/kasan/common.c > index 8428da2aaf17..66078cc1b4f0 100644 > --- a/mm/kasan/common.c > +++ b/mm/kasan/common.c > @@ -387,7 +387,7 @@ static inline bool ____kasan_kfree_large(void *ptr, u= nsigned long ip) > } > > /* > - * The object will be poisoned by kasan_free_pages() or > + * The object will be poisoned by kasan_poison_pages() or > * kasan_slab_free_mempool(). > */ > > diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c > index 7355cb534e4f..0b8225add2e4 100644 > --- a/mm/kasan/hw_tags.c > +++ b/mm/kasan/hw_tags.c > @@ -213,17 +213,6 @@ void kasan_alloc_pages(struct page *page, unsigned i= nt order, gfp_t flags) > } > } > > -void kasan_free_pages(struct page *page, unsigned int order) > -{ > - /* > - * This condition should match the one in free_pages_prepare() in > - * page_alloc.c. > - */ > - bool init =3D want_init_on_free(); > - > - kasan_poison_pages(page, order, init); > -} > - > #if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) > > void kasan_enable_tagging_sync(void) > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 3589333b5b77..3f3ea41f8c64 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1353,15 +1353,17 @@ static __always_inline bool free_pages_prepare(st= ruct page *page, > > /* > * As memory initialization might be integrated into KASAN, > - * kasan_free_pages and kernel_init_free_pages must be > + * KASAN poisoning and memory initialization code must be > * kept together to avoid discrepancies in behavior. > * > * With hardware tag-based KASAN, memory tags must be set before = the > * page becomes unavailable via debug_pagealloc or arch_free_page= . > */ > if (kasan_has_integrated_init()) { > + bool init =3D want_init_on_free(); > + > if (!skip_kasan_poison) > - kasan_free_pages(page, order); > + kasan_poison_pages(page, order, init); > } else { > bool init =3D want_init_on_free(); > > -- > 2.25.1 > > -- > You received this message because you are subscribed to the Google Groups= "kasan-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an= email to kasan-dev+unsubscribe@googlegroups.com. > To view this discussion on the web visit https://groups.google.com/d/msgi= d/kasan-dev/64f8b74a4766f886a6df77438e7e098205fd0863.1638308023.git.andreyk= nvl%40google.com. --=20 Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Stra=C3=9Fe, 33 80636 M=C3=BCnchen Gesch=C3=A4ftsf=C3=BChrer: Paul Manicle, Halimah DeLaine Prado Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg