Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752424AbdCAJwy (ORCPT ); Wed, 1 Mar 2017 04:52:54 -0500 Received: from mail-ua0-f178.google.com ([209.85.217.178]:32792 "EHLO mail-ua0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751637AbdCAJwu (ORCPT ); Wed, 1 Mar 2017 04:52:50 -0500 MIME-Version: 1.0 In-Reply-To: References: From: Dmitry Vyukov Date: Wed, 1 Mar 2017 10:44:49 +0100 Message-ID: Subject: Re: kvm: WARNING in nested_vmx_vmexit To: Wanpeng Li Cc: Paolo Bonzini , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , KVM list , LKML , Jim Mattson , Steve Rutherford , Haozhong Zhang , Xiao Guangrong , syzkaller Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2690 Lines: 56 On Wed, Mar 1, 2017 at 7:13 AM, Wanpeng Li wrote: > 2017-02-28 20:15 GMT+08:00 Dmitry Vyukov : >> Hello, >> >> The following program triggers WARNING in nested_vmx_vmexit: >> https://gist.githubusercontent.com/dvyukov/16b946d7dc703bb07b9b933f12fb8a6e/raw/dac60506feb8dd9dd22828c486e46ee8a5e30f13/gistfile1.txt >> >> >> ------------[ cut here ]------------ >> WARNING: CPU: 1 PID: 27742 at arch/x86/kvm/vmx.c:11029 >> nested_vmx_vmexit+0x5c35/0x74d0 arch/x86/kvm/vmx.c:11029 >> CPU: 1 PID: 27742 Comm: a.out Not tainted 4.10.0+ #229 >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 >> Call Trace: >> __dump_stack lib/dump_stack.c:15 [inline] >> dump_stack+0x2ee/0x3ef lib/dump_stack.c:51 >> panic+0x1fb/0x412 kernel/panic.c:179 >> __warn+0x1c4/0x1e0 kernel/panic.c:540 >> warn_slowpath_null+0x2c/0x40 kernel/panic.c:583 >> nested_vmx_vmexit+0x5c35/0x74d0 arch/x86/kvm/vmx.c:11029 >> vmx_leave_nested arch/x86/kvm/vmx.c:11136 [inline] >> vmx_set_msr+0x1565/0x1910 arch/x86/kvm/vmx.c:3324 >> kvm_set_msr+0xd4/0x170 arch/x86/kvm/x86.c:1099 >> do_set_msr+0x11e/0x190 arch/x86/kvm/x86.c:1128 >> __msr_io arch/x86/kvm/x86.c:2577 [inline] >> msr_io+0x24b/0x450 arch/x86/kvm/x86.c:2614 >> kvm_arch_vcpu_ioctl+0x35b/0x46a0 arch/x86/kvm/x86.c:3497 >> kvm_vcpu_ioctl+0x232/0x1120 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2721 >> vfs_ioctl fs/ioctl.c:43 [inline] >> do_vfs_ioctl+0x1bf/0x1790 fs/ioctl.c:683 >> SYSC_ioctl fs/ioctl.c:698 [inline] >> SyS_ioctl+0x8f/0xc0 fs/ioctl.c:689 >> entry_SYSCALL_64_fastpath+0x1f/0xc2 >> RIP: 0033:0x451229 >> RSP: 002b:00007fc1e7ebec98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 >> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000451229 >> RDX: 0000000020aecfe8 RSI: 000000004008ae89 RDI: 0000000000000008 >> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 >> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 >> R13: 0000000000000000 R14: 00007fc1e7ebf9c0 R15: 00007fc1e7ebf700 >> >> >> On commit e5d56efc97f8240d0b5d66c03949382b6d7e5570 > > I git checkout to this commit for linus tree, however the line number > 11029 doesn't match any warning, and there are several warnings in the > function nested_vmx_vmexit(), could you point out which one? Ah sorry, I have some local diff. So now I am on 86292b33d4b79ee03e2f43ea0381ef85f077c760 and here is my diff: https://gist.githubusercontent.com/dvyukov/6bb88c6e3584c3fd989df01386efcb74/raw/1ae08a3a682ad9467de5eb7fb96d457db514f9d2/gistfile1.txt The warning is: /* trying to cancel vmlaunch/vmresume is a bug */ WARN_ON_ONCE(vmx->nested.nested_run_pending);