From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: [PATCH kvm-unit-tests] Test fault during IRET from NMI. Date: Sun, 15 Sep 2013 11:17:01 +0300 Message-ID: <20130915081700.GU17294@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: pbonzini@redhat.com To: kvm@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:50562 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753250Ab3IOIRD (ORCPT ); Sun, 15 Sep 2013 04:17:03 -0400 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r8F8H2wM012838 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Sun, 15 Sep 2013 04:17:03 -0400 Content-Disposition: inline Sender: kvm-owner@vger.kernel.org List-ID: This test checks that NMI window opens only after IRET from NMI is executed without a fault. Signed-off-by: Gleb Natapov diff --git a/lib/x86/processor.h b/lib/x86/processor.h index e46d8d0..de1dc47 100644 --- a/lib/x86/processor.h +++ b/lib/x86/processor.h @@ -62,6 +62,13 @@ static inline u16 read_gs(void) return val; } +static inline unsigned long read_rflags(void) +{ + unsigned long f; + asm ("pushf; pop %0\n\t" : "=rm"(f)); + return f; +} + static inline void write_ds(unsigned val) { asm ("mov %0, %%ds" : : "rm"(val) : "memory"); diff --git a/x86/eventinj.c b/x86/eventinj.c index 7bed7c5..c171e30 100644 --- a/x86/eventinj.c +++ b/x86/eventinj.c @@ -125,6 +125,42 @@ static void nmi_isr(struct ex_regs *r) printf("After nested NMI to itself\n"); } +unsigned long after_iret_addr; + +static void nested_nmi_iret_isr(struct ex_regs *r) +{ + printf("Nested NMI isr running rip=%x\n", r->rip); + + if (r->rip == after_iret_addr) + test_count++; +} +static void nmi_iret_isr(struct ex_regs *r) +{ + unsigned long *s = alloc_page(); + test_count++; + printf("NMI isr running %p stack %p\n", &&after_iret, s); + handle_exception(2, nested_nmi_iret_isr); + printf("Try send nested NMI to itself\n"); + apic_self_nmi(); + printf("After nested NMI to itself\n"); + s[4] = read_ss(); + s[3] = 0; /* rsp */ + s[2] = read_rflags(); + s[1] = read_cs(); + s[0] = after_iret_addr = (unsigned long)&&after_iret; + asm ("mov %%rsp, %0\n\t" + "mov %1, %%rsp\n\t" + "outl %2, $0xe4\n\t" /* flush stack page */ +#ifdef __x86_64__ + "iretq\n\t" +#else + "iretl\n\t" +#endif + : "=m"(s[3]) : "rm"(&s[0]), "a"((unsigned int)virt_to_phys(s)) : "memory"); +after_iret: + printf("After iret\n"); +} + static void tirq0(isr_regs_t *r) { printf("irq0 running\n"); @@ -300,6 +336,20 @@ int main() irq_disable(); report("NMI", test_count == 2); + /* generate NMI that will fault on IRET */ + printf("Before NMI IRET test\n"); + test_count = 0; + handle_exception(2, nmi_iret_isr); + printf("Try send NMI to itself\n"); + apic_self_nmi(); + /* this is needed on VMX without NMI window notificatoin. + Interrupt windows is used instead, so let pending NMI + to be injected */ + irq_enable(); + asm volatile ("nop"); + irq_disable(); + printf("After NMI to itself\n"); + report("NMI", test_count == 2); #ifndef __x86_64__ stack_phys = (ulong)virt_to_phys(alloc_page()); stack_va = alloc_vpage(); -- Gleb.