From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B636F2EA726; Thu, 23 Oct 2025 08:06:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761206799; cv=none; b=IiKt5mttlc+prQ5Co2RprzC6hmOmT3SvoUzysyYATmBlUlFuoWZV5alPIzsLm41l7c3dabsb8DOrSNLagEsLmoQwou+Axt7TTM+9V9cAA1cKKWS62cW8BsQnJd07MLFQwwJqjgIt/6k89n4hxLgnopFm4x09A0ii0qyBD140pEw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761206799; c=relaxed/simple; bh=yS2cNc2lSf1U32xQcS3l1qxWUN4/5v2Uv+icT2OgTBI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=oCmCGU7taxyqS1XVQorfUMclWMlMkkjdGIVa76XDv4YpImRHaZ0EZjZTkDi+vY6uth6M8kz+LSJCm9b/s0cHmACxFfJq5ClKogIW5w1vTmqMlrgpB9iyrFNMX1KjzxQxfKpuGMOX1U6CGWjG0Z3Z5F+5buP0PAY7Oz5QdEmK3kA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=VXF5hsmg; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="VXF5hsmg" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=242WgqH1G7RN+Sb7WlH6cuKtkC+Sz9tXdy9IiSQ4nMw=; b=VXF5hsmgoKnX71LCCRK1VTH/qB 5Iw74PJQ9MB0sUkYBc60AIA9ycHfGe0KzUbpgT0UoPTfh8pqAMhEHasMXSAyPbnh/FW1YHv/sDt91 RagjJyW0JX7fj/kTWjKgbiMHpi0zuZyoV+HpTkHHDSWuSdMqj9DeZsG1rGZqlXJAcifb8YthNYkVS orFlbwvRwvDgsgkQ7WZfR185AgtE4GEQvxG/eiGK/yaH2HyXEEMsKOrTwZSIwjLfZxSyunzdUxplY g3wKEcMFfBFWGeDZodzpF1Le2p8iKXcUDLRd+6G+L3nUlJUAZ1sHkLtBA1GLhAJsR3nKa0mv3hL/Q eYjkpl3Q==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vBpTR-00000001Aqd-05Md; Thu, 23 Oct 2025 07:11:01 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id B9D0A300289; Thu, 23 Oct 2025 10:06:27 +0200 (CEST) Date: Thu, 23 Oct 2025 10:06:27 +0200 From: Peter Zijlstra To: "Xin Li (Intel)" Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, pbonzini@redhat.com, seanjc@google.com, corbet@lwn.net, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, andrew.cooper3@citrix.com, chao.gao@intel.com, hch@infradead.org Subject: Re: [PATCH v8 05/21] x86/cea: Export API for per-CPU exception stacks for KVM Message-ID: <20251023080627.GV3245006@noisy.programming.kicks-ass.net> References: <20251014010950.1568389-1-xin@zytor.com> <20251014010950.1568389-6-xin@zytor.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251014010950.1568389-6-xin@zytor.com> On Mon, Oct 13, 2025 at 06:09:34PM -0700, Xin Li (Intel) wrote: > FRED introduced new fields in the host-state area of the VMCS for stack > levels 1->3 (HOST_IA32_FRED_RSP[123]), each respectively corresponding to > per-CPU exception stacks for #DB, NMI and #DF. KVM must populate these > fields each time a vCPU is loaded onto a CPU. > +noinstr unsigned long __this_cpu_ist_top_va(enum exception_stack_ordering stack) > +{ > + return __this_cpu_ist_bottom_va(stack) + EXCEPTION_STKSZ; > +} > +EXPORT_SYMBOL(__this_cpu_ist_top_va); This has no business being a !GPL export. But please use: EXPORT_SYMBOL_FOR_MODULES(__this_cpu_ist_top_val, "kvm"); (or "kvm-intel", depending on which actual module ends up needing this symbol).