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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 60278C43458 for ; Fri, 10 Jul 2026 02:39:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: Content-Transfer-Encoding:Content-Type:In-Reply-To:From:References:To:Subject :MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=VAavuciIg1ufF/nLSzbvyqBHXP95xTYHvpXMTvIAkvE=; b=fmLHzwyIE1X18B Ppab6Liq4IUqpyXOGTlDwOvtTjE+BzL4FunlaeerbGBDDoJCeDhU2ZQim2WUe0ZJrtYQpQU8MgfZC ZUy7SEKbKLokDRFN3gCgEKvw51JNFbs5ToxeFQfoFZpBrnve+JkAbMiPdHoI9Qox58w6Kj31YTh/L sjAp3+/ehYzTS4silMEd6R5F3k/LQqWnecWfoqQ2oe+5r3Iq7DfMz+Q67r/cfG1uxoG+e4fMjn8hL wtsyXmzmiKGFD5JcSVaP+FNs85n02hGvBAP3Ho/45EznK9uyoByFoQixlVlCn9qMoEq0DZd6LetGr Yq/9Vrs8nN32N2KhJRDw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wi19A-00000003yS7-12vK; Fri, 10 Jul 2026 02:39:24 +0000 Received: from canpmsgout02.his.huawei.com ([113.46.200.217]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wi197-00000003yRd-2sci for linux-arm-kernel@lists.infradead.org; Fri, 10 Jul 2026 02:39:23 +0000 dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=VAavuciIg1ufF/nLSzbvyqBHXP95xTYHvpXMTvIAkvE=; b=kAZJ0w7zEcogApri4nexUiLh2HZrXG2vPQJ0/EFRqQsEGlLwjmVJaCrJosvj5fjxSBIj9SWNv ABjBGhDHvuMZaKhIsc/FAVoCQU3gkBOasyut0z+DGAXkKOsO3+ThUnR4d6M60DNnvg8v+8vsTPn lOIx974FF3e44yKm306pEVw= Received: from mail.maildlp.com (unknown [172.19.162.140]) by canpmsgout02.his.huawei.com (SkyGuard) with ESMTPS id 4gxG5D15WwzcZyH; Fri, 10 Jul 2026 10:30:08 +0800 (CST) Received: from dggpemf500011.china.huawei.com (unknown [7.185.36.131]) by mail.maildlp.com (Postfix) with ESMTPS id 7980F203C1; Fri, 10 Jul 2026 10:39:14 +0800 (CST) Received: from [10.67.109.254] (10.67.109.254) by dggpemf500011.china.huawei.com (7.185.36.131) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 10 Jul 2026 10:39:13 +0800 Message-ID: <454e79a0-78f8-4c8e-9fca-aad85a6a5aaa@huawei.com> Date: Fri, 10 Jul 2026 10:39:11 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 24/36] arm64: booting: Document boot requirements for FEAT_NMI To: Vladimir Murzin , References: <20260709121333.23507-1-vladimir.murzin@arm.com> <20260709121333.23507-25-vladimir.murzin@arm.com> From: Jinjie Ruan In-Reply-To: <20260709121333.23507-25-vladimir.murzin@arm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.109.254] X-ClientProxiedBy: kwepems500002.china.huawei.com (7.221.188.17) To dggpemf500011.china.huawei.com (7.185.36.131) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260709_193921_885404_BE5A7FC3 X-CRM114-Status: GOOD ( 14.79 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, maz@kernel.org, Mark Brown , catalin.marinas@arm.com, will@kernel.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 7/9/2026 8:13 PM, Vladimir Murzin wrote: > From: Mark Brown > > In order to use FEAT_NMI we must be able to use ALLINT, require that > it behave as though not trapped when it is present. > > Signed-off-by: Mark Brown > Signed-off-by: Ada Couprie Diaz > Signed-off-by: Vladimir Murzin > --- > Documentation/arch/arm64/booting.rst | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/Documentation/arch/arm64/booting.rst b/Documentation/arch/arm64/booting.rst > index 13ef311dace8..3170b26ae981 100644 > --- a/Documentation/arch/arm64/booting.rst > +++ b/Documentation/arch/arm64/booting.rst > @@ -568,6 +568,12 @@ Before jumping into the kernel, the following conditions must be met: > > - HCRX_EL2.EnASR (bit 2) must be initialised to 0b1. > > + For CPUs with support for Non-maskable Interrupts (FEAT_NMI): > + > + - If the kernel is entered at EL1 and EL2 is present: > + > + - HCRX_EL2.TALLINT (bit 6) must be initialised to 0b0. > + Reviewed-by: Jinjie Ruan > The requirements described above for CPU mode, caches, MMUs, architected > timers, coherency and system registers apply to all CPUs. All CPUs must > enter the kernel in the same exception level. Where the values documented