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 78E4EC6FD1C for ; Wed, 22 Mar 2023 17:52:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230294AbjCVRwH (ORCPT ); Wed, 22 Mar 2023 13:52:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51398 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230182AbjCVRwE (ORCPT ); Wed, 22 Mar 2023 13:52:04 -0400 Received: from mail-pg1-x54a.google.com (mail-pg1-x54a.google.com [IPv6:2607:f8b0:4864:20::54a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4562065113 for ; Wed, 22 Mar 2023 10:52:03 -0700 (PDT) Received: by mail-pg1-x54a.google.com with SMTP id e36-20020a631e24000000b0050f76fb84b6so3050979pge.8 for ; Wed, 22 Mar 2023 10:52:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; t=1679507523; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=iZTwETswiMkR6MsJjj+d7N8Pb7VPbOvVsKiiVr9TOhM=; b=i5+mifpqoOF/KxF3sUQl2/YU4M7kOnSQCVi7BGq43pujy0oUUBe8hPcWfsLGYLtG2m NSWswmC+HelxhvUeFVi96enYnxro0IrBcV1F8hUHYm6ihUptDyofwPVDeVmWnluPN4HP HRf5b33RDynRy5Y+O3asK9iHxQHDn7pOA9FXeGaGkmvyvvYPcU+Xo0AqeWHb75LvpXHh sEffnSPQ2LbrSDwhGGIpWGHUz6DtdDawZV5p6zKiRZT0zGS0Kv+JN6aMnb3fQ7nqDoyi T9Tu517oJGvpdQBkdLcni99k6uilxYjJokNEdA1jOwVCRoACOawG30Jl92aK1QIYTxQW +Arw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679507523; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=iZTwETswiMkR6MsJjj+d7N8Pb7VPbOvVsKiiVr9TOhM=; b=ospSy09kMA+IKSOdVkc938vI4ncuh61DQqlUGCyBvCEq0UubFjW0SmYbkc7BcAwVqQ WCinWtfyAC+GI5+vSiDEvkdLvo+452q5swbSa8DtXhWnQ85cb48ZYJLXSOa7MC732EKB T8IYW8xRi0TwPg2UHxNfmpdEZdXCQ4IdhQtuEuvFbdsgE4bhPRi+PZrQ7j+eua+0tsOc +hCfnUwN7g4hOtcccrSvXDaHv7qxY2vIm/zLKyHrWdndxcD/xpbre1LuVnag8XxAF0de cfJ2wVlt7i3YI9fFLX9sRlM3Mbb3DdQyOALPy6cGR4lhBsZwT5LJh4Ep9FKN4U+02aWQ lQXA== X-Gm-Message-State: AO0yUKW9mF1GnAqe6M0FQLGOcyfDQ8IUSF+x79Zy/aOCJNnU42ajtyZH dEuUBWB+cR//R41LtNhMuY9vdEc0xaU= X-Google-Smtp-Source: AK7set+RGHNA/eCwuNR2wbBn238UqLumF+xL7hx3F6oNRxE1rmepDqciOMOmxEg+y7rjgstoo1w3iS7S8xg= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:903:22c1:b0:1a0:6b23:7b55 with SMTP id y1-20020a17090322c100b001a06b237b55mr1415684plg.4.1679507522821; Wed, 22 Mar 2023 10:52:02 -0700 (PDT) Date: Wed, 22 Mar 2023 10:52:01 -0700 In-Reply-To: <20230307023946.14516-6-xin3.li@intel.com> Mime-Version: 1.0 References: <20230307023946.14516-1-xin3.li@intel.com> <20230307023946.14516-6-xin3.li@intel.com> Message-ID: Subject: Re: [PATCH v5 05/34] x86/traps: export external_interrupt() for VMX IRQ reinjection From: Sean Christopherson To: Xin Li Cc: linux-kernel@vger.kernel.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, peterz@infradead.org, andrew.cooper3@citrix.com, pbonzini@redhat.com, ravi.v.shankar@intel.com Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 06, 2023, Xin Li wrote: > To eliminate dispatching IRQ through the IDT, export external_interrupt() > for VMX IRQ reinjection. > > Tested-by: Shan Kang > Signed-off-by: Xin Li > --- > arch/x86/include/asm/traps.h | 2 ++ > arch/x86/kernel/traps.c | 14 ++++++++++++++ > 2 files changed, 16 insertions(+) > > diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h > index 46f5e4e2a346..da4c21ed68b4 100644 > --- a/arch/x86/include/asm/traps.h > +++ b/arch/x86/include/asm/traps.h > @@ -56,4 +56,6 @@ void __noreturn handle_stack_overflow(struct pt_regs *regs, > void f (struct pt_regs *regs) > typedef DECLARE_SYSTEM_INTERRUPT_HANDLER((*system_interrupt_handler)); > > +int external_interrupt(struct pt_regs *regs, unsigned int vector); > + > #endif /* _ASM_X86_TRAPS_H */ > diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c > index 31ad645be2fb..cebba1f49e19 100644 > --- a/arch/x86/kernel/traps.c > +++ b/arch/x86/kernel/traps.c > @@ -1540,6 +1540,20 @@ int external_interrupt(struct pt_regs *regs, unsigned int vector) > return 0; > } > > +#if IS_ENABLED(CONFIG_KVM_INTEL) > +/* > + * KVM VMX reinjects IRQ on its current stack, it's a sync call > + * thus the values in the pt_regs structure are not used in > + * executing IRQ handlers, except cs.RPL and flags.IF, which > + * are both always 0 in the VMX IRQ reinjection context. > + * > + * However, the pt_regs structure is sometimes used in stack > + * dump, e.g., show_regs(). So let the caller, i.e., KVM VMX > + * decide how to initialize the input pt_regs structure. > + */ > +EXPORT_SYMBOL_GPL(external_interrupt); > +#endif If the x86 maintainers don't object, I would prefer this to be squashed with the actual KVM usage, that way discussions on exactly what the exported API should be can be contained in a single thread.