* Claudio Fontana (cfont...@suse.de) wrote:
> On 5/27/21 12:53 PM, Claudio Fontana wrote:
> > On 5/27/21 11:48 AM, Claudio Fontana wrote:
> >> On 5/27/21 11:15 AM, Dr. David Alan Gilbert wrote:
> >>> * Philippe Mathieu-Daudé (phi...@redhat.com) wrote:
> >>>> On 5/27/21 10:31 AM, Dr. David Alan Gilbert wrote:
> >>>>> * Claudio Fontana (cfont...@suse.de) wrote:
> >>>>>> On 5/26/21 9:30 PM, Dr. David Alan Gilbert wrote:
> >>>>>>> * Michael S. Tsirkin (m...@redhat.com) wrote:
> >>>>>>>> On Fri, May 21, 2021 at 11:17:19AM +0200, Siddharth Chandrasekaran
> >>>>>>>> wrote:
> >>>>>>>>> After a rebase to QEMU master, I am having trouble booting windows
> >>>>>>>>> VMs.
> >>>>>>>>> Git bisect indicates commit f5cc5a5c1686 ("i386: split cpu
> >>>>>>>>> accelerators
> >>>>>>>>> from cpu.c, using AccelCPUClass") to have introduced the issue. I
> >>>>>>>>> spent
> >>>>>>>>> some time looking at into it yesterday without much luck.
> >>>>>>>>>
> >>>>>>>>> Steps to reproduce:
> >>>>>>>>>
> >>>>>>>>> $ ./configure --enable-kvm --disable-xen
> >>>>>>>>> --target-list=x86_64-softmmu --enable-debug
> >>>>>>>>> $ make -j `nproc`
> >>>>>>>>> $ ./build/x86_64-softmmu/qemu-system-x86_64 \
> >>>>>>>>> -cpu
> >>>>>>>>> host,hv_synic,hv_vpindex,hv_time,hv_runtime,hv_stimer,hv_crash \
> >>>>>>>>> -enable-kvm \
> >>>>>>>>> -name test,debug-threads=on \
> >>>>>>>>> -smp 1,threads=1,cores=1,sockets=1 \
> >>>>>>>>> -m 4G \
> >>>>>>>>> -net nic -net user \
> >>>>>>>>> -boot d,menu=on \
> >>>>>>>>> -usbdevice tablet \
> >>>>>>>>> -vnc :3 \
> >>>>>>>>> -machine q35,smm=on \
> >>>>>>>>> -drive
> >>>>>>>>> if=pflash,format=raw,readonly=on,unit=0,file="../OVMF_CODE.secboot.fd"
> >>>>>>>>> \
> >>>>>>>>> -drive
> >>>>>>>>> if=pflash,format=raw,unit=1,file="../OVMF_VARS.secboot.fd" \
> >>>>>>>>> -global ICH9-LPC.disable_s3=1 \
> >>>>>>>>> -global driver=cfi.pflash01,property=secure,value=on \
> >>>>>>>>> -cdrom "../Windows_Server_2016_14393.ISO" \
> >>>>>>>>> -drive
> >>>>>>>>> file="../win_server_2016.qcow2",format=qcow2,if=none,id=rootfs_drive
> >>>>>>>>> \
> >>>>>>>>> -device ahci,id=ahci \
> >>>>>>>>> -device ide-hd,drive=rootfs_drive,bus=ahci.0
> >>>>>>>>>
> >>>>>>>>> If the issue is not obvious, I'd like some pointers on how to go
> >>>>>>>>> about
> >>>>>>>>> fixing this issue.
> >>>>>>>>>
> >>>>>>>>> ~ Sid.
> >>>>>>>>>
> >>>>>>>>
> >>>>>>>> At a guess this commit inadvertently changed something in the CPU ID.
> >>>>>>>> I'd start by using a linux guest to dump cpuid before and after the
> >>>>>>>> change.
> >>>>>>>
> >>>>>>> I've not had a chance to do that yet, however I did just end up with a
> >>>>>>> bisect of a linux guest failure bisecting to the same patch:
> >>>>>>>
> >>>>>>> [dgilbert@dgilbert-t580 qemu]$ git bisect bad
> >>>>>>> f5cc5a5c168674f84bf061cdb307c2d25fba5448 is the first bad commit
> >>>>>>> commit f5cc5a5c168674f84bf061cdb307c2d25fba5448
> >>>>>>> Author: Claudio Fontana <cfont...@suse.de>
> >>>>>>> Date: Mon Mar 22 14:27:40 2021 +0100
> >>>>>>>
> >>>>>>> i386: split cpu accelerators from cpu.c, using AccelCPUClass
> >>>>>>>
> >>>>>>> i386 is the first user of AccelCPUClass, allowing to split
> >>>>>>> cpu.c into:
> >>>>>>>
> >>>>>>> cpu.c cpuid and common x86 cpu functionality
> >>>>>>> host-cpu.c host x86 cpu functions and "host" cpu type
> >>>>>>> kvm/kvm-cpu.c KVM x86 AccelCPUClass
> >>>>>>> hvf/hvf-cpu.c HVF x86 AccelCPUClass
> >>>>>>> tcg/tcg-cpu.c TCG x86 AccelCPUClass
> >>>>
> >>>> Well this is a big commit... I'm not custom to x86 target, and am
> >>>> having hard time following the cpu host/max change.
> >>>>
> >>>> Is it working when you use '-cpu max,...' instead of '-cpu host,'?
> >>>
> >>> No; and in fact the cpuid's are almost entirely different with and
> >>> without this patch! (both with -cpu host). It looks like with this
> >>> patch we're getting the cpuid for the TCG cpuid rather than the host:
> >>>
> >>> Prior to this patch:
> >>> :/# cat /proc/cpuinfo
> >>> processor : 0
> >>> vendor_id : GenuineIntel
> >>> cpu family : 6
> >>> model : 142
> >>> model name : Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz
> >>> stepping : 10
> >>> microcode : 0xe0
> >>> cpu MHz : 2111.998
> >>> cache size : 16384 KB
> >>> physical id : 0
> >>> siblings : 1
> >>> core id : 0
> >>> cpu cores : 1
> >>> apicid : 0
> >>> initial apicid : 0
> >>> fpu : yes
> >>> fpu_exception : yes
> >>> cpuid level : 22
> >>> wp : yes
> >>> flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
> >>> mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb rdtscp
> >>> lm constant
> >>> _tsc arch_perfmon rep_good nopl xtopology cpuid tsc_known_freq pni
> >>> pclmulqdq vmx ssse3 fma cx16 pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt
> >>> tsc_deadline_tim
> >>> er aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch
> >>> cpuid_fault invpcid_single pti ssbd ibrs ibpb stibp tpr_shadow vnmi
> >>> flexpriority ept vpid
> >>> ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx
> >>> rdseed adx smap clflushopt xsaveopt xsavec xgetbv1 xsaves arat umip
> >>> md_clear arch_ca
> >>> pabilities
> >>> vmx flags : vnmi preemption_timer invvpid ept_x_only ept_ad ept_1gb
> >>> flexpriority tsc_offset vtpr mtf vapic ept vpid unrestricted_guest
> >>> shadow_vmcs pml
> >>> bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass
> >>> l1tf mds swapgs taa srbds
> >>> bogomips : 4223.99
> >>> clflush size : 64
> >>> cache_alignment : 64
> >>> address sizes : 39 bits physical, 48 bits virtual
> >>> power management:
> >>>
> >>> With this patch:
> >>> processor : 0
> >>> vendor_id : AuthenticAMD
> >>> cpu family : 6
> >>> model : 6
> >>> model name : QEMU TCG CPU version 2.5+
> >>> stepping : 3
> >>> cpu MHz : 2111.998
> >>> cache size : 512 KB
> >>> physical id : 0
> >>> siblings : 1
> >>> core id : 0
> >>> cpu cores : 1
> >>> apicid : 0
> >>> initial apicid : 0
> >>> fpu : yes
> >>> fpu_exception : yes
> >>> cpuid level : 13
> >>> wp : yes
> >>> flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
> >>> mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb rdtscp
> >>> lm nopl cpu
> >>> id tsc_known_freq pni pclmulqdq vmx ssse3 fma cx16 pdcm pcid sse4_1
> >>> sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand
> >>> hypervisor lahf_
> >>> lm abm 3dnowprefetch invpcid_single ssbd ibrs ibpb stibp vmmcall fsgsbase
> >>> tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx rdseed adx smap
> >>> clflushopt
> >>> xsaveopt xsavec xgetbv1 xsaves arat umip md_clear arch_capabilities
> >>> bugs : fxsave_leak sysret_ss_attrs spectre_v1 spectre_v2
> >>> spec_store_bypass taa
> >>> bogomips : 4223.99
> >>> TLB size : 1024 4K pages
> >>> clflush size : 64
> >>> cache_alignment : 64
> >>> address sizes : 40 bits physical, 48 bits virtual
> >>> power management:
> >>>
> >>> cpuid.f5cc5a5c16
> >>>
> >>> CPU 0:
> >>> 0x00000000 0x00: eax=0x0000000d ebx=0x68747541 ecx=0x444d4163
> >>> edx=0x69746e65
> >>> 0x00000001 0x00: eax=0x00000663 ebx=0x00000800 ecx=0xfffab223
> >>> edx=0x0f8bfbff
> >>> 0x00000002 0x00: eax=0x00000001 ebx=0x00000000 ecx=0x0000004d
> >>> edx=0x002c307d
> >>> 0x00000003 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000004 0x00: eax=0x00000121 ebx=0x01c0003f ecx=0x0000003f
> >>> edx=0x00000001
> >>> 0x00000004 0x01: eax=0x00000122 ebx=0x01c0003f ecx=0x0000003f
> >>> edx=0x00000001
> >>> 0x00000004 0x02: eax=0x00000143 ebx=0x03c0003f ecx=0x00000fff
> >>> edx=0x00000001
> >>> 0x00000004 0x03: eax=0x00000163 ebx=0x03c0003f ecx=0x00003fff
> >>> edx=0x00000006
> >>> 0x00000005 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000003
> >>> edx=0x00000000
> >>> 0x00000006 0x00: eax=0x00000004 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000007 0x00: eax=0x00000000 ebx=0x009c4fbb ecx=0x00000004
> >>> edx=0xac000400
> >>> 0x00000008 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000009 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000a 0x00: eax=0x07300402 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00008603
> >>> 0x0000000b 0x00: eax=0x00000000 ebx=0x00000001 ecx=0x00000100
> >>> edx=0x00000000
> >>> 0x0000000b 0x01: eax=0x00000000 ebx=0x00000001 ecx=0x00000201
> >>> edx=0x00000000
> >>> 0x0000000c 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000d 0x00: eax=0x0000001f ebx=0x00000440 ecx=0x00000440
> >>> edx=0x00000000
> >>> 0x0000000d 0x01: eax=0x0000000f ebx=0x000003c0 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000d 0x02: eax=0x00000100 ebx=0x00000240 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000d 0x03: eax=0x00000040 ebx=0x000003c0 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000d 0x04: eax=0x00000040 ebx=0x00000400 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x40000000 0x00: eax=0x40000001 ebx=0x4b4d564b ecx=0x564b4d56
> >>> edx=0x0000004d
> >>> 0x40000001 0x00: eax=0x01007afb ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x80000000 0x00: eax=0x80000008 ebx=0x68747541 ecx=0x444d4163
> >>> edx=0x69746e65
> >>> 0x80000001 0x00: eax=0x00000663 ebx=0x00000000 ecx=0x00000121
> >>> edx=0x2d93fbff
> >>> 0x80000002 0x00: eax=0x554d4551 ebx=0x47435420 ecx=0x55504320
> >>> edx=0x72657620
> >>> 0x80000003 0x00: eax=0x6e6f6973 ebx=0x352e3220 ecx=0x0000002b
> >>> edx=0x00000000
> >>> 0x80000004 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x80000005 0x00: eax=0x01ff01ff ebx=0x01ff01ff ecx=0x40020140
> >>> edx=0x40020140
> >>> 0x80000006 0x00: eax=0x00000000 ebx=0x42004200 ecx=0x02008140
> >>> edx=0x00808140
> >>> 0x80000007 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x80000008 0x00: eax=0x00003028 ebx=0x0100d000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x80860000 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0xc0000000 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>>
> >>>
> >>> cpuid.0ac2b19743
> >>>
> >>> CPU 0:
> >>> 0x00000000 0x00: eax=0x00000016 ebx=0x756e6547 ecx=0x6c65746e
> >>> edx=0x49656e69
> >>> 0x00000001 0x00: eax=0x000806ea ebx=0x00000800 ecx=0xfffab223
> >>> edx=0x0f8bfbff
> >>> 0x00000002 0x00: eax=0x00000001 ebx=0x00000000 ecx=0x0000004d
> >>> edx=0x002c307d
> >>> 0x00000003 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000004 0x00: eax=0x00000121 ebx=0x01c0003f ecx=0x0000003f
> >>> edx=0x00000001
> >>> 0x00000004 0x01: eax=0x00000122 ebx=0x01c0003f ecx=0x0000003f
> >>> edx=0x00000001
> >>> 0x00000004 0x02: eax=0x00000143 ebx=0x03c0003f ecx=0x00000fff
> >>> edx=0x00000001
> >>> 0x00000004 0x03: eax=0x00000163 ebx=0x03c0003f ecx=0x00003fff
> >>> edx=0x00000006
> >>> 0x00000005 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000003
> >>> edx=0x00000000
> >>> 0x00000006 0x00: eax=0x00000004 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000007 0x00: eax=0x00000000 ebx=0x009c4fbb ecx=0x00000004
> >>> edx=0xac000400
> >>> 0x00000008 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000009 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000a 0x00: eax=0x07300402 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00008603
> >>> 0x0000000b 0x00: eax=0x00000000 ebx=0x00000001 ecx=0x00000100
> >>> edx=0x00000000
> >>> 0x0000000b 0x01: eax=0x00000000 ebx=0x00000001 ecx=0x00000201
> >>> edx=0x00000000
> >>> 0x0000000c 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000d 0x00: eax=0x0000001f ebx=0x00000440 ecx=0x00000440
> >>> edx=0x00000000
> >>> 0x0000000d 0x01: eax=0x0000000f ebx=0x000003c0 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000d 0x02: eax=0x00000100 ebx=0x00000240 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000d 0x03: eax=0x00000040 ebx=0x000003c0 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000d 0x04: eax=0x00000040 ebx=0x00000400 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000e 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x0000000f 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000010 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000011 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000012 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000013 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000014 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000015 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x00000016 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x40000000 0x00: eax=0x40000001 ebx=0x4b4d564b ecx=0x564b4d56
> >>> edx=0x0000004d
> >>> 0x40000001 0x00: eax=0x01007afb ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x80000000 0x00: eax=0x80000008 ebx=0x756e6547 ecx=0x6c65746e
> >>> edx=0x49656e69
> >>> 0x80000001 0x00: eax=0x000806ea ebx=0x00000000 ecx=0x00000121
> >>> edx=0x2c100800
> >>> 0x80000002 0x00: eax=0x65746e49 ebx=0x2952286c ecx=0x726f4320
> >>> edx=0x4d542865
> >>> 0x80000003 0x00: eax=0x37692029 ebx=0x3536382d ecx=0x43205530
> >>> edx=0x40205550
> >>> 0x80000004 0x00: eax=0x392e3120 ebx=0x7a484730 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x80000005 0x00: eax=0x01ff01ff ebx=0x01ff01ff ecx=0x40020140
> >>> edx=0x40020140
> >>> 0x80000006 0x00: eax=0x00000000 ebx=0x42004200 ecx=0x02008140
> >>> edx=0x00808140
> >>> 0x80000007 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x80000008 0x00: eax=0x00003027 ebx=0x0100d000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0x80860000 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>> 0xc0000000 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000
> >>> edx=0x00000000
> >>>
> >>
> >> I started looking at it.
> >>
> >> Claudio
> >>
> >
> > I wonder how I missed this, the initialization functions for
> > max_x86_cpu_initfn and kvm_cpu_max_instance_init end up being called in the
> > wrong order.
> >
>
>
> Just to check whether this is actually the issue we are talking about, Sid et
> al, could you try this?
>
>
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index c496bfa1c2..810c46281b 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -4252,6 +4252,7 @@ static void max_x86_cpu_initfn(Object *obj)
> object_property_set_str(OBJECT(cpu), "model-id",
> "QEMU TCG CPU version " QEMU_HW_VERSION,
> &error_abort);
> + accel_cpu_instance_init(CPU(cpu));
> }
>
> static const TypeInfo max_x86_cpu_type_info = {
> ------------------------------------------------------------------------------------------
>
> Does this band-aid happen to cover-up the issue?
I think it mostly does - thanks; however the address widths are still
wrong:
address sizes : 40 bits physical, 48 bits virtual
where as my little laptop can only think in 39bits physical; so I think
that's still coming through from the TCG def.
Dave
>
> I need to think about the proper fix though, any suggestions Paolo, Eduardo?
>
> The pickle here is that we'd need to call the accelerator specific
> initialization of the x86 accel-cpu only after the x86 cpu subclass initfn,
> otherwise the accel-specific cpu initialization code has no chance to see the
> subclass (max) trying to set ->max_features.
>
> C.
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
