From patchwork Thu Nov 10 05:53:46 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13038301 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 CE3FBC4332F for ; Thu, 10 Nov 2022 06:17:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232397AbiKJGR0 (ORCPT ); Thu, 10 Nov 2022 01:17:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232353AbiKJGRV (ORCPT ); Thu, 10 Nov 2022 01:17:21 -0500 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 972492ED74 for ; Wed, 9 Nov 2022 22:17:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1668061040; x=1699597040; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=btiN7wu6yHcG/APG6+UAvWqTkcuTq8Wkw/RVvQEA/KE=; b=UFuDICDlXM8XDuj2dEHsuV/OkRV5rSadt0Edbr2WtgP7jds61PvQSyLq Rc5ybyF4u7sPNbeWpyr+xH3VN/6ZmB7lQOqPmhwMo1ZPlZQYNSwktGEQa QtdJ24yBbTgyj65BdikoK30srYDYpIQdicfP0PWG81MqWr+UjmcFo6DAh GRD+tAlT+XTF6FPP6aD9ME5C/K7HbIIXMVrC5UO2hxpBBSAgSnWtJj1G/ hUO6SYTcWzNpSfgSc3iuWhPshbAU4ozz3OixXFRAWqe/nGlKkQaRQyA4Y T1ZOdv6nxZHC4Nwg4iTTldScwAnXX79iLL+IHWRJ6ZA4iGnRYwcIVaDXO Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10526"; a="311223528" X-IronPort-AV: E=Sophos;i="5.96,152,1665471600"; d="scan'208";a="311223528" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Nov 2022 22:17:18 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10526"; a="700667274" X-IronPort-AV: E=Sophos;i="5.96,152,1665471600"; d="scan'208";a="700667274" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga008.fm.intel.com with ESMTP; 09 Nov 2022 22:17:17 -0800 From: Xin Li To: linux-kernel@vger.kernnel.org, x86@kernel.org, kvm@vger.kernel.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, seanjc@google.com, pbonzini@redhat.com, kevin.tian@intel.com Subject: [PATCH 5/6] KVM: x86/VMX: add kvm_vmx_reinject_nmi_irq() for NMI/IRQ reinjection Date: Wed, 9 Nov 2022 21:53:46 -0800 Message-Id: <20221110055347.7463-6-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221110055347.7463-1-xin3.li@intel.com> References: <20221110055347.7463-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org To eliminate dispatching NMI/IRQ through the IDT, add kvm_vmx_reinject_nmi_irq(), which calls external_interrupt() for IRQ reinjection. Lastly replace calling a NMI/IRQ handler in an IDT descriptor with calling kvm_vmx_reinject_nmi_irq(). Signed-off-by: H. Peter Anvin (Intel) Signed-off-by: Xin Li --- arch/x86/include/asm/traps.h | 2 ++ arch/x86/kernel/traps.c | 23 +++++++++++++++++++++++ arch/x86/kvm/vmx/vmenter.S | 33 --------------------------------- arch/x86/kvm/vmx/vmx.c | 19 +++++++------------ 4 files changed, 32 insertions(+), 45 deletions(-) diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h index 89c4233e19db..4c56a8d31762 100644 --- a/arch/x86/include/asm/traps.h +++ b/arch/x86/include/asm/traps.h @@ -57,4 +57,6 @@ void __noreturn handle_stack_overflow(struct pt_regs *regs, unsigned long vector __maybe_unused) typedef DECLARE_SYSTEM_INTERRUPT_HANDLER((*system_interrupt_handler)); +void kvm_vmx_reinject_nmi_irq(u32 vector); + #endif /* _ASM_X86_TRAPS_H */ diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index c1eb3bd335ce..9abf91534b13 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -1528,6 +1528,29 @@ __visible noinstr void external_interrupt(struct pt_regs *regs, common_interrupt(regs, vector); } +#if IS_ENABLED(CONFIG_KVM_INTEL) +/* + * KVM VMX reinjects NMI/IRQ on its current stack, it's a sync + * call thus the values in the pt_regs structure are not used in + * executing NMI/IRQ handlers, except cs.RPL and flags.IF, which + * are both always 0 in the VMX NMI/IRQ reinjection context. Thus + * we simply allocate a zeroed pt_regs structure on current stack + * to call external_interrupt(). + */ +void kvm_vmx_reinject_nmi_irq(u32 vector) +{ + struct pt_regs irq_regs; + + memset(&irq_regs, 0, sizeof(irq_regs)); + + if (vector == NMI_VECTOR) + return exc_nmi(&irq_regs); + + external_interrupt(&irq_regs, vector); +} +EXPORT_SYMBOL_GPL(kvm_vmx_reinject_nmi_irq); +#endif + void __init trap_init(void) { /* Init cpu_entry_area before IST entries are set up */ diff --git a/arch/x86/kvm/vmx/vmenter.S b/arch/x86/kvm/vmx/vmenter.S index 8477d8bdd69c..0c1608b329cd 100644 --- a/arch/x86/kvm/vmx/vmenter.S +++ b/arch/x86/kvm/vmx/vmenter.S @@ -317,36 +317,3 @@ SYM_FUNC_START(vmread_error_trampoline) RET SYM_FUNC_END(vmread_error_trampoline) - -SYM_FUNC_START(vmx_do_interrupt_nmi_irqoff) - /* - * Unconditionally create a stack frame, getting the correct RSP on the - * stack (for x86-64) would take two instructions anyways, and RBP can - * be used to restore RSP to make objtool happy (see below). - */ - push %_ASM_BP - mov %_ASM_SP, %_ASM_BP - -#ifdef CONFIG_X86_64 - /* - * Align RSP to a 16-byte boundary (to emulate CPU behavior) before - * creating the synthetic interrupt stack frame for the IRQ/NMI. - */ - and $-16, %rsp - push $__KERNEL_DS - push %rbp -#endif - pushf - push $__KERNEL_CS - CALL_NOSPEC _ASM_ARG1 - - /* - * "Restore" RSP from RBP, even though IRET has already unwound RSP to - * the correct value. objtool doesn't know the callee will IRET and, - * without the explicit restore, thinks the stack is getting walloped. - * Using an unwind hint is problematic due to x86-64's dynamic alignment. - */ - mov %_ASM_BP, %_ASM_SP - pop %_ASM_BP - RET -SYM_FUNC_END(vmx_do_interrupt_nmi_irqoff) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 63247c57c72c..b457e4888468 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -46,6 +46,7 @@ #include #include #include +#include #include #include @@ -6758,15 +6759,11 @@ static void vmx_apicv_post_state_restore(struct kvm_vcpu *vcpu) memset(vmx->pi_desc.pir, 0, sizeof(vmx->pi_desc.pir)); } -void vmx_do_interrupt_nmi_irqoff(unsigned long entry); - -static void handle_interrupt_nmi_irqoff(struct kvm_vcpu *vcpu, - unsigned long entry) +static void handle_interrupt_nmi_irqoff(struct kvm_vcpu *vcpu, u32 vector) { - bool is_nmi = entry == (unsigned long)asm_exc_nmi_noist; - - kvm_before_interrupt(vcpu, is_nmi ? KVM_HANDLING_NMI : KVM_HANDLING_IRQ); - vmx_do_interrupt_nmi_irqoff(entry); + kvm_before_interrupt(vcpu, vector == NMI_VECTOR ? + KVM_HANDLING_NMI : KVM_HANDLING_IRQ); + kvm_vmx_reinject_nmi_irq(vector); kvm_after_interrupt(vcpu); } @@ -6792,7 +6789,6 @@ static void handle_nm_fault_irqoff(struct kvm_vcpu *vcpu) static void handle_exception_nmi_irqoff(struct vcpu_vmx *vmx) { - const unsigned long nmi_entry = (unsigned long)asm_exc_nmi_noist; u32 intr_info = vmx_get_intr_info(&vmx->vcpu); /* if exit due to PF check for async PF */ @@ -6806,20 +6802,19 @@ static void handle_exception_nmi_irqoff(struct vcpu_vmx *vmx) kvm_machine_check(); /* We need to handle NMIs before interrupts are enabled */ else if (is_nmi(intr_info)) - handle_interrupt_nmi_irqoff(&vmx->vcpu, nmi_entry); + handle_interrupt_nmi_irqoff(&vmx->vcpu, NMI_VECTOR); } static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu) { u32 intr_info = vmx_get_intr_info(vcpu); unsigned int vector = intr_info & INTR_INFO_VECTOR_MASK; - gate_desc *desc = (gate_desc *)host_idt_base + vector; if (KVM_BUG(!is_external_intr(intr_info), vcpu->kvm, "KVM: unexpected VM-Exit interrupt info: 0x%x", intr_info)) return; - handle_interrupt_nmi_irqoff(vcpu, gate_offset(desc)); + handle_interrupt_nmi_irqoff(vcpu, vector); vcpu->arch.at_instruction_boundary = true; }