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 6C333C636CC for ; Wed, 8 Feb 2023 17:01:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E30676B0071; Wed, 8 Feb 2023 12:01:18 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id DE13D6B0072; Wed, 8 Feb 2023 12:01:18 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CA7D66B0074; Wed, 8 Feb 2023 12:01:18 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id B75146B0071 for ; Wed, 8 Feb 2023 12:01:18 -0500 (EST) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 8030D80E3B for ; Wed, 8 Feb 2023 17:01:18 +0000 (UTC) X-FDA: 80444740236.02.47C196D Received: from mail-yw1-f179.google.com (mail-yw1-f179.google.com [209.85.128.179]) by imf24.hostedemail.com (Postfix) with ESMTP id 6E2E9180035 for ; Wed, 8 Feb 2023 17:01:16 +0000 (UTC) Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=IYDBhhuM; spf=pass (imf24.hostedemail.com: domain of elver@google.com designates 209.85.128.179 as permitted sender) smtp.mailfrom=elver@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1675875676; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=xXdBKFQFjb45PJbE0WfevTYuOvd7Ed4TIGS1v3lQONw=; b=thmu6hFhJDMRcUwKlHzMqD7jv7+DewoKr68LHb0uWRB5e9VNZ7ZPYg34Cpb4C9qrvoPpeQ bmyuIGj2Zg3YLcNfCIq4o2ZJb+zeVXcoiTruKzKqMIxDZwFVd+h1VTbMpznLsSvqVrJRU7 wx3aXnGEHVPXa3npsyJqSOt+zsM8xiM= ARC-Authentication-Results: i=1; imf24.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=IYDBhhuM; spf=pass (imf24.hostedemail.com: domain of elver@google.com designates 209.85.128.179 as permitted sender) smtp.mailfrom=elver@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1675875676; a=rsa-sha256; cv=none; b=bb7WiQgRWMe7ZOFfFqLTRCUfkMNfVddDQXh7BWP1iYt7AZ5qzUsUhhGOjzEXM4tf/0WepQ 12lhvyXb5XUBDHQu8qvJlUZfdIzeoykdZpEM8pMBgJ0MnmUSZKG5QsowUUgInjhXjDN7ZS Ot0cERyPptbCvJCgti5kuHpc/fuUV/I= Received: by mail-yw1-f179.google.com with SMTP id 00721157ae682-52be9c49c07so26467017b3.3 for ; Wed, 08 Feb 2023 09:01:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=xXdBKFQFjb45PJbE0WfevTYuOvd7Ed4TIGS1v3lQONw=; b=IYDBhhuMNLvOxMUNieuhwuuF9uXlY3Q40X9spez9yj/kTGor601E2JU44ZjwWer7ei CeWzoNfmFFnK2djRuZgotnT9X//bTMkS1g2gfcj6/jhIrR0Hzt3NeBwrQjz+AGNvZeLv YoZsYffzCQi8itKIDcn4dTasqFfs57kAnrU6ikZsgOF7kCIKtFbInx3tElCxew6PfN1y 1EvjFBk8vCctHzYB3k3xkgfsCoOe4cQ/Wr6d9I50G9aiCWf2oSjDQc9nSiU7uK8aXI4s IoaofrnXVS55YOGefRunieUPutdwkmW4EQRElQYvLag/FUXG51SOY/BFn0OcvmYgTSp6 5vCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=xXdBKFQFjb45PJbE0WfevTYuOvd7Ed4TIGS1v3lQONw=; b=I0ve8ebBllm+TAo+U+WZJfaa62ZsDN8rRFKhnzpMdSWUNazoORn7OnRH8aynWV5TvM DuZj/wF+EcTMolbCo6CQLwdS4Yr1ZQjaz41kms0ZpEz+y2SPJI54MbSPu/JLcd5m5X/j R1V4yluBrGY15hPdwVrV3deMeAjX+DHhYePC5AZqxO1SwADCvHnpAMybnJhwBBRuw3+d hr6u0m2Tx+f1ggEfwK61UreIFFBcYReRVmSWhwc3u0UFbgqmx/CD9SXZholNWI27s2ZC ahnC6w7xlzssiNV7Ju61h83F1098o6pYVtFhIvn+UXYJ7gUxa19r6XCrFOa07CLkU9ZU d21A== X-Gm-Message-State: AO0yUKWTi//Oh1d6xybxHIO6g7KKP3VtyjdFgOZMPdKo9uia64Vp654e o6zDmgdUju89ittok+6MGD2PtvOJI87oIX5rUQY29w== X-Google-Smtp-Source: AK7set+cXrZJrfRBDM8O463q/uWZDKhuEYG0A6IIhrhL+2YLEgmuhPgKCxOXMuOmKcmi1rOzXNkSd3J5BIJj/WAfcRE= X-Received: by 2002:a81:9e07:0:b0:527:b49f:b89 with SMTP id m7-20020a819e07000000b00527b49f0b89mr937260ywj.176.1675875675180; Wed, 08 Feb 2023 09:01:15 -0800 (PST) MIME-Version: 1.0 References: <20230208164011.2287122-1-arnd@kernel.org> <20230208164011.2287122-2-arnd@kernel.org> In-Reply-To: <20230208164011.2287122-2-arnd@kernel.org> From: Marco Elver Date: Wed, 8 Feb 2023 18:00:38 +0100 Message-ID: Subject: Re: [PATCH 2/4] kmsan: disable ftrace in kmsan core code To: Arnd Bergmann Cc: Josh Poimboeuf , Peter Zijlstra , Alexander Potapenko , Andrew Morton , kasan-dev@googlegroups.com, Dmitry Vyukov , Andrey Ryabinin , Vincenzo Frascino , Andrey Konovalov , Arnd Bergmann , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 6E2E9180035 X-Stat-Signature: 53o6qakahq1t68xnej6tdf73gbh5684y X-HE-Tag: 1675875676-684571 X-HE-Meta: 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 tZdo8d4i 0hgCcqxP6M34T2NvP+dC3XUpJghBY7f9/CeZbhV5tupy39kpb/HBBYumLVkdpC+PJXIXzxrdY4Cw2ULqdlhL9tNcnobTRuynqTQNO0sEu102MjX2oCukWAmBr7E3aimhXS+3zePXYaL97a6SOBef9wbM3vulSydYxWoj1LpDSXXet8XEnTwuTGzW7iewp7sN+rF7N6AT8pfq61j52Mw/Sfx4dLLB2clysUGn8BkT/uQ2IZLZD/myHP3BDzsngwd6+tgsUnnee3iI+IdPgiF+WZxtRnzEIQfZOa7ZFRz2bEJndXKYGWzjujGod02gR+BD8lwVgIKoGoq/GLQkXQYitst3qjvgk9yXJ6iBlIxfWag1m0jkVXbCyvV7sNw== 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, 8 Feb 2023 at 17:40, Arnd Bergmann wrote: > > From: Arnd Bergmann > > objtool warns about some suspicous code inside of kmsan: > > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_load_n+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_store_n+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_load_1+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_store_1+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_load_2+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_store_2+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_load_4+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_store_4+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_load_8+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_store_8+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_instrument_asm_store+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_chain_origin+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_poison_alloca+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_warning+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_get_context_state+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: kmsan_copy_to_user+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: kmsan_unpoison_memory+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: kmsan_unpoison_entry_regs+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: kmsan_report+0x4: call to __fentry__() with UACCESS enabled > > Similar code already exists in kasan, which avoids this by skipping > ftrace annotations, so do the same thing here. > > Fixes: f80be4571b19 ("kmsan: add KMSAN runtime core") > Signed-off-by: Arnd Bergmann > --- > mm/kmsan/Makefile | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/mm/kmsan/Makefile b/mm/kmsan/Makefile > index 98eab2856626..389fd767a11f 100644 > --- a/mm/kmsan/Makefile > +++ b/mm/kmsan/Makefile > @@ -16,6 +16,14 @@ CC_FLAGS_KMSAN_RUNTIME += -DDISABLE_BRANCH_PROFILING > > CFLAGS_REMOVE.o = $(CC_FLAGS_FTRACE) That means this CFLAGS_REMOVE.o didn't work, right? Can it be removed? > +# Disable ftrace to avoid recursion. > +CFLAGS_REMOVE_core.o = $(CC_FLAGS_FTRACE) > +CFLAGS_REMOVE_hooks.o = $(CC_FLAGS_FTRACE) > +CFLAGS_REMOVE_init.o = $(CC_FLAGS_FTRACE) > +CFLAGS_REMOVE_instrumentation.o = $(CC_FLAGS_FTRACE) > +CFLAGS_REMOVE_report.o = $(CC_FLAGS_FTRACE) > +CFLAGS_REMOVE_shadow.o = $(CC_FLAGS_FTRACE) > + > CFLAGS_core.o := $(CC_FLAGS_KMSAN_RUNTIME) > CFLAGS_hooks.o := $(CC_FLAGS_KMSAN_RUNTIME) > CFLAGS_init.o := $(CC_FLAGS_KMSAN_RUNTIME) > -- > 2.39.1 >