Re: regression bisected; KVM: entry failed, hardware error 0x80000021

["Chen, Tiejun" <tiejun.chen@intel.com>]

On 2014/12/24 19:11, Paolo Bonzini wrote:
>
>
> On 24/12/2014 12:02, Jamie Heilman wrote:
>> Running qemu-system-x86_64 -machine pc,accel=kvm -nodefaults works,
>> my real (headless) kvm guests work, but this new patch makes running
>> "qemu-system-x86_64 -machine pc,accel=kvm" fail again, this time with
>> errors in the host to the tune of:
>>
>> ------------[ cut here ]------------
>> WARNING: CPU: 1 PID: 3901 at arch/x86/kvm/x86.c:6575 kvm_arch_vcpu_ioctl_run+0xd63/0xe5b [kvm]()
>> Modules linked in: nfsv4 cpufreq_userspace cpufreq_stats cpufreq_powersave cpufreq_ondemand cpufreq_conservative autofs4 fan nfsd auth_rpcgss nfs lockd grace fscache sunrpc bridge stp llc vhost_net tun vhost macvtap macvlan fuse cbc dm_crypt usb_storage snd_hda_codec_analog snd_hda_codec_generic kvm_intel kvm tg3 ptp pps_core sr_mod snd_hda_intel snd_hda_controller snd_hda_codec snd_hwdep snd_pcm snd_timer snd sg dcdbas cdrom psmouse soundcore floppy evdev xfs dm_mod raid1 md_mod
>> CPU: 1 PID: 3901 Comm: qemu-system-x86 Not tainted 3.19.0-rc1-00011-g53262d1-dirty #1
>> Hardware name: Dell Inc. Precision WorkStation T3400  /0TP412, BIOS A14 04/30/2012
>>   0000000000000000 000000007e052328 ffff8800c25ffcf8 ffffffff813defbe
>>   0000000000000000 0000000000000000 ffff8800c25ffd38 ffffffff8103b517
>>   ffff8800c25ffd28 ffffffffa019bdec ffff8800caf1d000 ffff8800c2774800
>> Call Trace:
>>   [<ffffffff813defbe>] dump_stack+0x4c/0x6e
>>   [<ffffffff8103b517>] warn_slowpath_common+0x97/0xb1
>>   [<ffffffffa019bdec>] ? kvm_arch_vcpu_ioctl_run+0xd63/0xe5b [kvm]
>>   [<ffffffff8103b60b>] warn_slowpath_null+0x15/0x17
>>   [<ffffffffa019bdec>] kvm_arch_vcpu_ioctl_run+0xd63/0xe5b [kvm]
>>   [<ffffffffa02308b9>] ? vmcs_load+0x20/0x62 [kvm_intel]
>>   [<ffffffffa0231e03>] ? vmx_vcpu_load+0x140/0x16a [kvm_intel]
>>   [<ffffffffa0196ba3>] ? kvm_arch_vcpu_load+0x15c/0x161 [kvm]
>>   [<ffffffffa018d8b1>] kvm_vcpu_ioctl+0x189/0x4bd [kvm]
>>   [<ffffffff8104647a>] ? do_sigtimedwait+0x12f/0x189
>>   [<ffffffff810ea316>] do_vfs_ioctl+0x370/0x436
>>   [<ffffffff810f24f2>] ? __fget+0x67/0x72
>>   [<ffffffff810ea41b>] SyS_ioctl+0x3f/0x5e
>>   [<ffffffff813e34d2>] system_call_fastpath+0x12/0x17
>> ---[ end trace 46abac932fb3b4a1 ]---
>> ------------[ cut here ]------------
>> WARNING: CPU: 1 PID: 3901 at arch/x86/kvm/x86.c:6575 kvm_arch_vcpu_ioctl_run+0xd63/0xe5b [kvm]()
>> Modules linked in: nfsv4 cpufreq_userspace cpufreq_stats cpufreq_powersave cpufreq_ondemand cpufreq_conservative autofs4 fan nfsd auth_rpcgss nfs lockd grace fscache sunrpc bridge stp llc vhost_net tun vhost macvtap macvlan fuse cbc dm_crypt usb_storage snd_hda_codec_analog snd_hda_codec_generic kvm_intel kvm tg3 ptp pps_core sr_mod snd_hda_intel snd_hda_controller snd_hda_codec snd_hwdep snd_pcm snd_timer snd sg dcdbas cdrom psmouse soundcore floppy evdev xfs dm_mod raid1 md_mod
>> CPU: 1 PID: 3901 Comm: qemu-system-x86 Tainted: G        W      3.19.0-rc1-00011-g53262d1-dirty #1
>> Hardware name: Dell Inc. Precision WorkStation T3400  /0TP412, BIOS A14 04/30/2012
>>   0000000000000000 000000007e052328 ffff8800c25ffcf8 ffffffff813defbe
>>   0000000000000000 0000000000000000 ffff8800c25ffd38 ffffffff8103b517
>>   ffff8800c25ffd28 ffffffffa019bdec ffff8800caf1d000 ffff8800c2774800
>> Call Trace:
>>   [<ffffffff813defbe>] dump_stack+0x4c/0x6e
>>   [<ffffffff8103b517>] warn_slowpath_common+0x97/0xb1
>>   [<ffffffffa019bdec>] ? kvm_arch_vcpu_ioctl_run+0xd63/0xe5b [kvm]
>>   [<ffffffff8103b60b>] warn_slowpath_null+0x15/0x17
>>   [<ffffffffa019bdec>] kvm_arch_vcpu_ioctl_run+0xd63/0xe5b [kvm]
>>   [<ffffffffa02308b9>] ? vmcs_load+0x20/0x62 [kvm_intel]
>>   [<ffffffffa0231e03>] ? vmx_vcpu_load+0x140/0x16a [kvm_intel]
>>   [<ffffffffa0196ba3>] ? kvm_arch_vcpu_load+0x15c/0x161 [kvm]
>>   [<ffffffffa018d8b1>] kvm_vcpu_ioctl+0x189/0x4bd [kvm]
>>   [<ffffffff8104647a>] ? do_sigtimedwait+0x12f/0x189
>>   [<ffffffff810ea316>] do_vfs_ioctl+0x370/0x436
>>   [<ffffffff810f24f2>] ? __fget+0x67/0x72
>>   [<ffffffff810ea41b>] SyS_ioctl+0x3f/0x5e
>>   [<ffffffff813e34d2>] system_call_fastpath+0x12/0x17
>> ---[ end trace 46abac932fb3b4a2 ]---
>>
>> over and over and over ad nauseum, or until I kill the qemu command,
>> it also eats a core's worth of cpu.

Such a message above seems to be out of our mem_slot issue, I'm not 100% 
sure but actually I can run this case,

qemu-system-x86_64 -machine pc,accel=kvm -m 2048 -smp 2 -hda ubuntu.img

Just one patch, "kvm: x86: vmx: reorder some msr writing", is needed 
here. So I guess you guy can try to pull your 3.19-rc1 + that patch, and 
also pull qemu.

>
> Yeah, I'm fairly sure that the second hunk of Tiejun's patch is not
> correct, but he's on the right track.  I hope to post a fix today, else

Yeah, looks that will broken !next case then I regenerate that again 
post into another email. Now at lease I myself can run Andy's next case 
and a normal case, "qemu-system-x86_64 -machine pc,accel=kvm", at the 
same time. But if I'm missing something please correct me directly :)

Tiejun