From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="gyb2sOjs" Received: from mail-qv1-xf36.google.com (mail-qv1-xf36.google.com [IPv6:2607:f8b0:4864:20::f36]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E956BB8 for ; Thu, 16 Nov 2023 02:34:20 -0800 (PST) Received: by mail-qv1-xf36.google.com with SMTP id 6a1803df08f44-677a12f1362so3280476d6.1 for ; Thu, 16 Nov 2023 02:34:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1700130860; x=1700735660; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=nCzmGpWmQul4wYiJvXX4QGBTD7ZNE9De5NBHM0dQ8JI=; b=gyb2sOjsJh64yKJY92DI+11XTUrz8vDPBIhiPDzickHe91aBE/zIxmv8ULiXtESFXr WFhtxbCeO7szK3OscKGPMOE9YvjJw6vuepxbOHI4lN4tURE40V5i9ffpwArWa58F1Tu5 e7yBhlSJ5pRUMSwpYccwKW0n07sCcpqMueIE2DlQcuARCjNv5MVqASNXadm+5TDUYs7i 95QyRu7wjL4yWCXHJRJ2n8oOqQ5PpiTnRKj2TFb+E2EYoa7guUHZAS3eaM9q81UH32PD sOhndC+NtXoXchkWdE5Wn5CYl2mdsnoa7T16vcleNbzN4Wf7m5koykXDGaLm45kaQ4RE 3Fmw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700130860; x=1700735660; h=content-transfer-encoding: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=nCzmGpWmQul4wYiJvXX4QGBTD7ZNE9De5NBHM0dQ8JI=; b=su4gcm8rsvq5mCS4SiCvO1v2wPg5VsU/UVjOwavYh7oDt4Gebn039MiFLmrt4u7ELX gGLZ7tte/9dxaFSCqU/kRgWiOGmWN/kg5EJRE4z9iK7kCvQHxo0bxAdM6DxgVAVWuP/O R5uDGZsbT9KHx4kietxMRXSuqj46sXB0ycygZMPLQ2GnOqNYuJMlE61LKYHtSyizD/aZ bZ0mPSbdzJH+v0KYcQu/Nd6b/zBL2Fba+wyJkW6X0mGDzJWE6DKww1Db851sIl/swyXD XA2KP06jvGICdloi10EiFQn5YkRn/eirZx4uwh9InQ8VQrC8HZWMAfPFOkz9UbFvALGb QYUg== X-Gm-Message-State: AOJu0Yyh1bYPMutlS4s1Ha8dlEUBBtxJrfHQ0iZz3Kc1hRwnVl2WM5l1 uJPNNSgsf9BqBDyFAxlsrUT3Ohqg3zYXW0dv2pljsw== X-Google-Smtp-Source: AGHT+IG4aY9GHR76tVKMTAGmd0CseNMuUXkNiPOGtMWZyskYlNgHZ6XGDtn1AzcetJJpwAPmQpPFevQ/edxH5B4nbxw= X-Received: by 2002:a05:6214:12d3:b0:66d:1d3f:17d7 with SMTP id s19-20020a05621412d300b0066d1d3f17d7mr7472430qvv.8.1700130859918; Thu, 16 Nov 2023 02:34:19 -0800 (PST) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20231115203401.2495875-1-iii@linux.ibm.com> <20231115203401.2495875-20-iii@linux.ibm.com> In-Reply-To: <20231115203401.2495875-20-iii@linux.ibm.com> From: Alexander Potapenko Date: Thu, 16 Nov 2023 11:33:43 +0100 Message-ID: Subject: Re: [PATCH 19/32] kmsan: Accept ranges starting with 0 on s390 To: Ilya Leoshkevich Cc: Alexander Gordeev , Andrew Morton , Christoph Lameter , David Rientjes , Joonsoo Kim , Marco Elver , Masami Hiramatsu , Pekka Enberg , Steven Rostedt , Vasily Gorbik , Vlastimil Babka , Christian Borntraeger , Dmitry Vyukov , Hyeonggon Yoo <42.hyeyoo@gmail.com>, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-s390@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Mark Rutland , Roman Gushchin , Sven Schnelle Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, Nov 15, 2023 at 9:34=E2=80=AFPM Ilya Leoshkevich wrote: > > On s390 the virtual address 0 is valid (current CPU's lowcore is mapped > there), therefore KMSAN should not complain about it. > > Disable the respective check on s390. There doesn't seem to be a > Kconfig option to describe this situation, so explicitly check for > s390. > > Signed-off-by: Ilya Leoshkevich Reviewed-by: Alexander Potapenko (see the nit below) > --- > mm/kmsan/init.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/mm/kmsan/init.c b/mm/kmsan/init.c > index ffedf4dbc49d..14f4a432fddd 100644 > --- a/mm/kmsan/init.c > +++ b/mm/kmsan/init.c > @@ -33,7 +33,9 @@ static void __init kmsan_record_future_shadow_range(voi= d *start, void *end) > bool merged =3D false; > > KMSAN_WARN_ON(future_index =3D=3D NUM_FUTURE_RANGES); > - KMSAN_WARN_ON((nstart >=3D nend) || !nstart || !nend); > + KMSAN_WARN_ON((nstart >=3D nend) || > + (!IS_ENABLED(CONFIG_S390) && !nstart) || Please add a comment explaining this bit. > + !nend); > nstart =3D ALIGN_DOWN(nstart, PAGE_SIZE); > nend =3D ALIGN(nend, PAGE_SIZE); > > -- > 2.41.0 >