From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752881AbbIWH4l (ORCPT ); Wed, 23 Sep 2015 03:56:41 -0400 Received: from mail.skyhub.de ([78.46.96.112]:60103 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752318AbbIWH4j (ORCPT ); Wed, 23 Sep 2015 03:56:39 -0400 Date: Wed, 23 Sep 2015 09:56:36 +0200 From: Borislav Petkov To: Paolo Bonzini Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Subject: Re: [PATCH] KVM: x86: fix bogus warning about reserved bits Message-ID: <20150923075635.GA3564@pd.tnic> References: <1442910329-3357-1-git-send-email-pbonzini@redhat.com> <20150922175647.GC3568@pd.tnic> <5601C266.4060601@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <5601C266.4060601@redhat.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 22, 2015 at 11:04:38PM +0200, Paolo Bonzini wrote: > Let's add more debugging output: Here you go: [ 50.474002] walk_shadow_page_get_mmio_spte: detect reserved bits on spte, addr 0xb8000 (level 4, 0xf0000000000f8) [ 50.484249] walk_shadow_page_get_mmio_spte: detect reserved bits on spte, addr 0xb8000 (level 3, 0xf000000000078) [ 50.494492] walk_shadow_page_get_mmio_spte: detect reserved bits on spte, addr 0xb8000 (level 2, 0xf000000000078) [ 50.504767] dump hierarchy: [ 50.507595] ------ spte 0x416533027 level 4. [ 50.507595] ------ spte 0x416534027 level 3. [ 50.507596] ------ spte 0x416535027 level 2. [ 50.507596] ------ spte 0xffff0000000b8f67 level 1. [ 50.507597] ------------[ cut here ]------------ [ 50.507616] WARNING: CPU: 4 PID: 3539 at arch/x86/kvm/mmu.c:3396 handle_mmio_page_fault.part.57+0x1a/0x20 [kvm]() [ 50.507630] Modules linked in: tun sha256_ssse3 sha256_generic drbg binfmt_misc ipv6 vfat fat fuse dm_crypt dm_mod kvm_amd kvm crc32_pclmul aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd amd64_edac_mod k10temp edac_core fam15h_power amdkfd amd_iommu_v2 radeon acpi_cpufreq [ 50.507632] CPU: 4 PID: 3539 Comm: qemu-system-x86 Not tainted 4.3.0-rc2+ #2 [ 50.507633] Hardware name: To be filled by O.E.M. To be filled by O.E.M./M5A97 EVO R2.0, BIOS 1503 01/16/2013 [ 50.507635] ffffffffa0433932 ffff880416973b78 ffffffff812c758a 0000000000000000 [ 50.507637] ffff880416973bb0 ffffffff810534c1 ffff8804231c0000 000000000000000f [ 50.507638] 00000000000b8000 0000000000000000 00000000ffffffff ffff880416973bc0 [ 50.507639] Call Trace: [ 50.507643] [] dump_stack+0x4e/0x84 [ 50.507646] [] warn_slowpath_common+0x91/0xd0 [ 50.507647] [] warn_slowpath_null+0x1a/0x20 [ 50.507657] [] handle_mmio_page_fault.part.57+0x1a/0x20 [kvm] [ 50.507667] [] tdp_page_fault+0x2a0/0x2b0 [kvm] [ 50.507673] [] ? __lock_acquire+0x57d/0x17a0 [ 50.507682] [] kvm_mmu_page_fault+0x35/0x240 [kvm] [ 50.507685] [] pf_interception+0x108/0x1d0 [kvm_amd] [ 50.507688] [] handle_exit+0x150/0xa40 [kvm_amd] [ 50.507697] [] ? kvm_arch_vcpu_ioctl_run+0x4c8/0x16f0 [kvm] [ 50.507706] [] kvm_arch_vcpu_ioctl_run+0x533/0x16f0 [kvm] [ 50.507715] [] ? kvm_arch_vcpu_ioctl_run+0x4c8/0x16f0 [kvm] [ 50.507717] [] ? mutex_lock_killable_nested+0x312/0x480 [ 50.507724] [] ? kvm_vcpu_ioctl+0x79/0x6f0 [kvm] [ 50.507726] [] ? preempt_count_sub+0xb3/0x110 [ 50.507733] [] kvm_vcpu_ioctl+0x33f/0x6f0 [kvm] [ 50.507735] [] do_vfs_ioctl+0x2d7/0x530 [ 50.507737] [] ? __fget_light+0x29/0x90 [ 50.507738] [] SyS_ioctl+0x4c/0x90 [ 50.507740] [] entry_SYSCALL_64_fastpath+0x16/0x73 [ 50.507741] ---[ end trace ff23795fcc279cbd ]--- > Thus same as before. > > Just to be safe, can you try using "-cpu host" on the QEMU command > line and see if it changes anything? This would catch things such > as an Intel CPUID on an AMD host. Here's my full qemu command: qemu-system-x86_64 -enable-kvm -gdb tcp::1234 -cpu host -m 2048 -hda /home/boris/kvm/debian/sid-x86_64.img -hdb /home/boris/kvm/swap.img -boot menu=off,order=c -localtime -net nic,model=rtl8139 -net user,hostfwd=tcp::1235-:22 -usbdevice tablet -kernel /home/boris/kernel/linux-2.6/arch/x86/boot/bzImage -append "root=/dev/sda1 resume=/dev/sdb1 debug ignore_loglevel log_buf_len=16M earlyprintk=ttyS0,115200 console=ttyS0,115200 console=tty0 " -monitor pty -virtfs local,path=/tmp,mount_tag=tmp,security_model=none -serial file:/home/boris/kvm/test-x86_64-1235.log -snapshot -name "Debian x86_64:1235" -smp 8 and that splats too: [ 146.891735] walk_shadow_page_get_mmio_spte: detect reserved bits on spte, addr 0xb8000 (level 4, 0xf0000000000f8) [ 146.901981] walk_shadow_page_get_mmio_spte: detect reserved bits on spte, addr 0xb8000 (level 3, 0xf000000000078) [ 146.912224] walk_shadow_page_get_mmio_spte: detect reserved bits on spte, addr 0xb8000 (level 2, 0xf000000000078) [ 146.922496] dump hierarchy: [ 146.925331] ------ spte 0x37d47027 level 4. [ 146.925332] ------ spte 0x37d46027 level 3. [ 146.925332] ------ spte 0xb9faa027 level 2. [ 146.925333] ------ spte 0xffff0000000b8f67 level 1. [ 146.925333] ------------[ cut here ]------------ [ 146.925351] WARNING: CPU: 6 PID: 3753 at arch/x86/kvm/mmu.c:3396 handle_mmio_page_fault.part.57+0x1a/0x20 [kvm]() [ 146.925371] Modules linked in: tun sha256_ssse3 sha256_generic drbg binfmt_misc ipv6 vfat fat fuse dm_crypt dm_mod kvm_amd kvm crc32_pclmul aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd amd64_edac_mod k10temp edac_core fam15h_power amdkfd amd_iommu_v2 radeon acpi_cpufreq [ 146.925373] CPU: 6 PID: 3753 Comm: qemu-system-x86 Tainted: G W 4.3.0-rc2+ #2 [ 146.925374] Hardware name: To be filled by O.E.M. To be filled by O.E.M./M5A97 EVO R2.0, BIOS 1503 01/16/2013 [ 146.925376] ffffffffa0433932 ffff880423377b78 ffffffff812c758a 0000000000000000 [ 146.925378] ffff880423377bb0 ffffffff810534c1 ffff88042315bf00 000000000000000f [ 146.925379] 00000000000b8000 0000000000000000 00000000ffffffff ffff880423377bc0 [ 146.925380] Call Trace: [ 146.925384] [] dump_stack+0x4e/0x84 [ 146.925386] [] warn_slowpath_common+0x91/0xd0 [ 146.925388] [] warn_slowpath_null+0x1a/0x20 [ 146.925397] [] handle_mmio_page_fault.part.57+0x1a/0x20 [kvm] [ 146.925408] [] tdp_page_fault+0x2a0/0x2b0 [kvm] [ 146.925410] [] ? __lock_acquire+0x57d/0x17a0 [ 146.925420] [] kvm_mmu_page_fault+0x35/0x240 [kvm] [ 146.925423] [] pf_interception+0x108/0x1d0 [kvm_amd] [ 146.925431] [] handle_exit+0x150/0xa40 [kvm_amd] [ 146.925440] [] ? kvm_arch_vcpu_ioctl_run+0x4c8/0x16f0 [kvm] [ 146.925449] [] kvm_arch_vcpu_ioctl_run+0x533/0x16f0 [kvm] [ 146.925458] [] ? kvm_arch_vcpu_ioctl_run+0x4c8/0x16f0 [kvm] [ 146.925461] [] ? mutex_lock_killable_nested+0x312/0x480 [ 146.925467] [] ? kvm_vcpu_ioctl+0x79/0x6f0 [kvm] [ 146.925469] [] ? preempt_count_sub+0xb3/0x110 [ 146.925476] [] kvm_vcpu_ioctl+0x33f/0x6f0 [kvm] [ 146.925478] [] do_vfs_ioctl+0x2d7/0x530 [ 146.925480] [] ? __fget_light+0x29/0x90 [ 146.925481] [] SyS_ioctl+0x4c/0x90 [ 146.925482] [] entry_SYSCALL_64_fastpath+0x16/0x73 [ 146.925484] ---[ end trace ff23795fcc279cbe ]--- Thanks. -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply.