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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0F58CC4332F for ; Fri, 11 Nov 2022 09:19:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233210AbiKKJTf (ORCPT ); Fri, 11 Nov 2022 04:19:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38430 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231615AbiKKJTe (ORCPT ); Fri, 11 Nov 2022 04:19:34 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 79D472613C for ; Fri, 11 Nov 2022 01:19:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=cMMCcucAsGolv5//xqeEzkd07EWyc4Atda4dDWbFHy8=; b=Oc8acBiGdRATRfe+O9YnPMxlem bqr13X35I316iYolHjKsPsnuUZqDwc0r6gCekigzu1X1lzS7nduPUivpegYixS4PQray6Sy0SZS4H l3OHicAB9HUKFyXWr7NFNIB4FdYWBOnVpCpqsh3Wv0VFRtyZtGD5YOnm8ymHtI2p7gAu+1MX5rL8S 13Gvn82ighn5NNn8hs0xwmJZCpriIb2GNsGSAgpwac1ep3DWNpTxuuzpMxAHrL+5Yo/5IoEeuc9/6 SXpDFJqJ/nk0VzOgUonJ+TXL1dIJdRrAOBZye5A3HZz+rhIq1IOJQB+gRrWipNg8+6Gia21BQYwSA 2UstXtVQ==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1otQC9-00Ctj7-69; Fri, 11 Nov 2022 09:19:29 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 5D8C930031B; Fri, 11 Nov 2022 10:19:23 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 41E8720243A99; Fri, 11 Nov 2022 10:19:23 +0100 (CET) Date: Fri, 11 Nov 2022 10:19:23 +0100 From: Peter Zijlstra To: Sean Christopherson Cc: "Li, Xin3" , "linux-kernel@vger.kernnel.org" , "x86@kernel.org" , "kvm@vger.kernel.org" , "tglx@linutronix.de" , "mingo@redhat.com" , "bp@alien8.de" , "dave.hansen@linux.intel.com" , "hpa@zytor.com" , "pbonzini@redhat.com" , "Tian, Kevin" Subject: Re: [PATCH 5/6] KVM: x86/VMX: add kvm_vmx_reinject_nmi_irq() for NMI/IRQ reinjection Message-ID: References: <20221110055347.7463-1-xin3.li@intel.com> <20221110055347.7463-6-xin3.li@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Nov 10, 2022 at 08:53:09PM +0000, Sean Christopherson wrote: > On Thu, Nov 10, 2022, Li, Xin3 wrote: > > > > + * call thus the values in the pt_regs structure are not used in > > > > + * executing NMI/IRQ handlers, > > > > > > Won't this break stack traces to some extent? > > > > > > > The pt_regs structure, and its IP/CS, is NOT part of the call stack, thus > > I don't see a problem. No? I'm not sure what Xin3 is trying to say, but NMI/IRQ handers use pt_regs a *LOT*. pt_regs *MUST* be correct.