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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1993C433F5 for ; Wed, 20 Oct 2021 07:23:49 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4955D60FD8 for ; Wed, 20 Oct 2021 07:23:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 4955D60FD8 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 9CA566B0071; Wed, 20 Oct 2021 03:23:48 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 952D86B0072; Wed, 20 Oct 2021 03:23:48 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7F411900002; Wed, 20 Oct 2021 03:23:48 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0248.hostedemail.com [216.40.44.248]) by kanga.kvack.org (Postfix) with ESMTP id 697146B0071 for ; Wed, 20 Oct 2021 03:23:48 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 24286181AF5C6 for ; Wed, 20 Oct 2021 07:23:48 +0000 (UTC) X-FDA: 78715976136.16.3003EDC Received: from mail-ot1-f51.google.com (mail-ot1-f51.google.com [209.85.210.51]) by imf25.hostedemail.com (Postfix) with ESMTP id 05AA6B00008E for ; Wed, 20 Oct 2021 07:23:43 +0000 (UTC) Received: by mail-ot1-f51.google.com with SMTP id b4-20020a9d7544000000b00552ab826e3aso5247037otl.4 for ; Wed, 20 Oct 2021 00:23:47 -0700 (PDT) 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; bh=kU2IPRL8ftmwSTb+WFMJqCEa8tDzkDYqWbLRrE2BrPc=; b=Z9H2n0S4Jqv5TODlbAm7IEoBWEjHonzCDw5KhMOcpgcNdwafYI5hl846Do/Y9Ou8J4 Nh9OI+lYpQzGZMNfGRO5QbZ3+xMSih4c4Sek/fz3wq3jfaA/UhQ2PmJWPIEmt6QuquOL TP0BXd6qyBb1af+2OwX6ri4+SwH+99imu7LTzy8zZbi5ghPzIVwiN653Ye0nq5o+rrrC E4zVgo7S5oKkaq+dyNLBBqBDm+vGVzYTAXQ3mV25+maP2TZbNC3ej7WdCTsqIr+v6DVp 6eWasHRDjPiSmADHQhTkCVqLTX0SCxJjzT13WM6fvlfGRBPkhyjzxRa1lZ2XjHzTBFeA w0zQ== 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; bh=kU2IPRL8ftmwSTb+WFMJqCEa8tDzkDYqWbLRrE2BrPc=; b=dG/po4gcFEobTxrYpKfjcFIGfQZPVyHLC12PwcSKDf+WtaXq9/smj+hBJUbs985DrW 3KvZuKgHjljM4WT+QmJOhXPv6Z9UkVUQNqHezD09gsbDLKLzVRTyGbccKXRGk814eyyt yODk2CUkl4ciSf2zRFxVFr9iEl4oUaPzJq8rWYPlMzbCrgwpjMx8HD9aZK+Q0YXY25As RvWCORVx+NmTnU2gZ9Ml/SD5dByrWU7Mixs1raZSO7EbkmDFdWCvuLCf/tMDvyERRDCm nGaDPpxh+Gto+qZ5yYZd1hhd/x5jcmPWAfEHhpC5hR08Y8seKrU1hY+mH1JcPccD3Y+H tcCQ== X-Gm-Message-State: AOAM530EH+5ciIipyRwrAXgtVxmJukyrLk0rY0mbZsaebizkSnGk2Rrb 2BEcsg4a0UNvs30jA4UIjkVLGbZpQpM3bt3Afu6/Aw== X-Google-Smtp-Source: ABdhPJxYaB/xUITs/EEyisEF1CX0Q9AbBpoCaL8yuO7fy/xV4PTxIosNxyf5PIF+8caN552qxFShQqzctqUgQlFvyzY= X-Received: by 2002:a9d:2ac2:: with SMTP id e60mr1361127otb.92.1634714627015; Wed, 20 Oct 2021 00:23:47 -0700 (PDT) MIME-Version: 1.0 References: <20211020061248.13270-1-Kuan-Ying.Lee@mediatek.com> In-Reply-To: <20211020061248.13270-1-Kuan-Ying.Lee@mediatek.com> From: Marco Elver Date: Wed, 20 Oct 2021 09:23:35 +0200 Message-ID: Subject: Re: [PATCH v2] kasan: add kasan mode messages when kasan init To: Kuan-Ying Lee Cc: Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Catalin Marinas , Will Deacon , Andrew Morton , Matthias Brugger , chinwen.chang@mediatek.com, yee.lee@mediatek.com, nicholas.tang@mediatek.com, kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-mediatek@lists.infradead.org Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 05AA6B00008E X-Stat-Signature: 564fxp98m5bchzi1xgdzh19rtctbhxam Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=Z9H2n0S4; spf=pass (imf25.hostedemail.com: domain of elver@google.com designates 209.85.210.51 as permitted sender) smtp.mailfrom=elver@google.com; dmarc=pass (policy=reject) header.from=google.com X-HE-Tag: 1634714623-821783 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 Wed, 20 Oct 2021 at 08:13, Kuan-Ying Lee wrote: > > There are multiple kasan modes. It makes sense that we add some messages > to know which kasan mode is when booting up. see [1]. > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=212195 [1] > Signed-off-by: Kuan-Ying Lee > --- > change since v2: > - Rebase to linux-next > - HW-tags based mode need to consider asymm mode > - Thanks for Marco's suggestion > > arch/arm64/mm/kasan_init.c | 2 +- > mm/kasan/hw_tags.c | 4 +++- > mm/kasan/kasan.h | 10 ++++++++++ > mm/kasan/sw_tags.c | 2 +- > 4 files changed, 15 insertions(+), 3 deletions(-) > > diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c > index 5b996ca4d996..6f5a6fe8edd7 100644 > --- a/arch/arm64/mm/kasan_init.c > +++ b/arch/arm64/mm/kasan_init.c > @@ -309,7 +309,7 @@ void __init kasan_init(void) > kasan_init_depth(); > #if defined(CONFIG_KASAN_GENERIC) > /* CONFIG_KASAN_SW_TAGS also requires kasan_init_sw_tags(). */ > - pr_info("KernelAddressSanitizer initialized\n"); > + pr_info("KernelAddressSanitizer initialized (generic)\n"); > #endif > } > > diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c > index dc892119e88f..1d5c89c7cdfe 100644 > --- a/mm/kasan/hw_tags.c > +++ b/mm/kasan/hw_tags.c > @@ -177,7 +177,9 @@ void __init kasan_init_hw_tags(void) > break; > } > > - pr_info("KernelAddressSanitizer initialized\n"); > + pr_info("KernelAddressSanitizer initialized (hw-tags, mode=%s, stacktrace=%s)\n", > + kasan_mode_info(), > + kasan_stack_collection_enabled() ? "on" : "off"); > } > > void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags) > diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h > index aebd8df86a1f..387ed7b6de37 100644 > --- a/mm/kasan/kasan.h > +++ b/mm/kasan/kasan.h > @@ -36,6 +36,16 @@ static inline bool kasan_sync_fault_possible(void) > { > return kasan_mode == KASAN_MODE_SYNC || kasan_mode == KASAN_MODE_ASYMM; > } > + > +static inline const char *kasan_mode_info(void) > +{ > + if (kasan_mode == KASAN_MODE_ASYNC) > + return "async"; > + else if (kasan_mode == KASAN_MODE_ASYMM) > + return "asymm"; > + else > + return "sync"; > +} This creates an inconsistency, because for kasan_stack_collection_enabled(), kasan_async_fault_possible(), and kasan_sync_fault_possible() there are !KASAN_HW_TAGS stubs. A stub for kasan_mode_info() if !KASAN_HW_TAGS appears useless though, and I wouldn't know what its return value should be. Do you expect this helper to be used outside hw_tags.c? If not, perhaps just move it into hw_tags.c. Thanks, -- Marco