| Message ID | 528B561C.9070200@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 19.11.2013 13:14, Paolo Bonzini wrote: > Il 19/11/2013 13:03, Peter Lieven ha scritto: >>> Can you test which of these two work? But I agree it's best to disable >>> cache-leaf forwarding. >> The first does make windows boot again and it calculates a >> correct combination of cpus, threads, cores and sockets. But >> I think the reason it boots is because cores=threads=1. >> >> As its more intuitive (I think) I would prefer your "cores over threads >> over socket ". >> The last thing I would think of is emulating more than 1 socket. -smp N >> would then mean, N cores, no hyper-threading, 1 socket. > After looking more at the docs, I think I found the bug. Can you test this? > > diff --git a/target-i386/cpu.c b/target-i386/cpu.c > index 864c80e..16d4db1 100644 > --- a/target-i386/cpu.c > +++ b/target-i386/cpu.c > @@ -2086,14 +2086,10 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count, > /* cache info: needed for Core compatibility */ > if (cpu->cache_info_passthrough) { > host_cpuid(index, count, eax, ebx, ecx, edx); > - break; > - } > - if (cs->nr_cores > 1) { > - *eax = (cs->nr_cores - 1) << 26; > + *eax &= ~0xFC000000; > } else { > *eax = 0; > - } > - switch (count) { > + switch (count) { > case 0: /* L1 dcache info */ > *eax |= CPUID_4_TYPE_DCACHE | \ > CPUID_4_LEVEL(1) | \ > @@ -2118,9 +2114,6 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count, > *eax |= CPUID_4_TYPE_UNIFIED | \ > CPUID_4_LEVEL(2) | \ > CPUID_4_SELF_INIT_LEVEL; > - if (cs->nr_threads > 1) { > - *eax |= (cs->nr_threads - 1) << 14; > - } > *ebx = (L2_LINE_SIZE - 1) | \ > ((L2_PARTITIONS - 1) << 12) | \ > ((L2_ASSOCIATIVITY - 1) << 22); > @@ -2133,6 +2126,12 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count, > *ecx = 0; > *edx = 0; > break; > + } > + } > + > + /* We give out APIC IDs ourselves, so force bits 31..26 even for "-cpu host". */ > + if (cs->nr_cores > 1) { > + *eax |= (cs->nr_cores - 1) << 26; > } > break; > case 5: > > Paolo I already tried exactly this fix. Its reading index 0x0000004 for increasing indexes until qemu aborts: ~/git/qemu$ x86_64-softmmu/qemu-system-x86_64 -m 2048 -drive if=virtio,file=iscsi://172.21.200.45/iqn.2001-05.com.equallogic:0-8a0906-9d95c510a-344001d54795289f-2012-r2-1-7-0/0,format=raw,cache=writeback,aio=native -cpu host -monitor stdio -vnc :1 -enable-kvm -usb -usbdevice tablet -vga cirrus -global virtio-blk-pci.scsi=off -smp 4,cores=4,threads=1,sockets=1 -serial null -parallel null -boot c (qemu) cpuid_data is full, no space for cpuid(eax:0x4,ecx:0x5d) Abgebrochen (Speicherabzug geschrieben) If you really want to have this feature: a) fix smp_parse and leave it at "prefer sockets over cores over threads", but use your new code: if (cpus == 0) { sockets = sockets > 0 ? sockets : 1; cores = cores > 0 ? cores : 1; threads = threads > 0 ? threads : 1; cpus = cores * threads * sockets; } else if (sockets == 0) { cores = cores > 0 ? cores : 1; threads = threads > 0 ? threads : 1; sockets = cpus / (cores * threads); } else if (cores == 0) { threads = threads > 0 ? threads : 1; cores = cpus / (sockets * threads); } else { threads = cpus / (sockets * cores); } b) disable cache leaf pass-thru as soon as threads*cores > 1. It seems to work as long as there is only one core with one thread per socket. Peter
Il 19/11/2013 13:32, Peter Lieven ha scritto: >> >> + >> + /* We give out APIC IDs ourselves, so force bits 31..26 even >> for "-cpu host". */ >> + if (cs->nr_cores > 1) { >> + *eax |= (cs->nr_cores - 1) << 26; >> } >> break; >> case 5: > > I already tried exactly this fix. Its reading index 0x0000004 for > increasing indexes until qemu aborts: Oops, it should be I guess "if ((*eax & 31) && cs->nr_cores > 1)". Paolo > ~/git/qemu$ x86_64-softmmu/qemu-system-x86_64 -m 2048 -drive > if=virtio,file=iscsi://172.21.200.45/iqn.2001-05.com.equallogic:0-8a0906-9d95c510a-344001d54795289f-2012-r2-1-7-0/0,format=raw,cache=writeback,aio=native > -cpu host -monitor stdio -vnc :1 -enable-kvm -usb -usbdevice tablet -vga > cirrus -global virtio-blk-pci.scsi=off -smp > 4,cores=4,threads=1,sockets=1 -serial null -parallel null -boot c
On 19.11.2013 14:21, Paolo Bonzini wrote: > Il 19/11/2013 13:32, Peter Lieven ha scritto: >>> + >>> + /* We give out APIC IDs ourselves, so force bits 31..26 even >>> for "-cpu host". */ >>> + if (cs->nr_cores > 1) { >>> + *eax |= (cs->nr_cores - 1) << 26; >>> } >>> break; >>> case 5: >> I already tried exactly this fix. Its reading index 0x0000004 for >> increasing indexes until qemu aborts: > Oops, it should be I guess "if ((*eax & 31) && cs->nr_cores > 1)". Maybe, how should we continue. This should be fixed before 1.7 comes out. Peter
Il 19/11/2013 15:11, Peter Lieven ha scritto: >>>> >>> I already tried exactly this fix. Its reading index 0x0000004 for >>> increasing indexes until qemu aborts: >> Oops, it should be I guess "if ((*eax & 31) && cs->nr_cores > 1)". > Maybe, how should we continue. This should be fixed before 1.7 comes out. If this works, I'll post a patch. Paolo
On 19.11.2013 15:14, Paolo Bonzini wrote:
> if ((*eax & 31) && cs->nr_cores > 1)
at which position exactly do you want to put this condition and take which action?
Peter
diff --git a/target-i386/cpu.c b/target-i386/cpu.c index 864c80e..16d4db1 100644 --- a/target-i386/cpu.c +++ b/target-i386/cpu.c @@ -2086,14 +2086,10 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count, /* cache info: needed for Core compatibility */ if (cpu->cache_info_passthrough) { host_cpuid(index, count, eax, ebx, ecx, edx); - break; - } - if (cs->nr_cores > 1) { - *eax = (cs->nr_cores - 1) << 26; + *eax &= ~0xFC000000; } else { *eax = 0; - } - switch (count) { + switch (count) { case 0: /* L1 dcache info */ *eax |= CPUID_4_TYPE_DCACHE | \ CPUID_4_LEVEL(1) | \ @@ -2118,9 +2114,6 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count, *eax |= CPUID_4_TYPE_UNIFIED | \ CPUID_4_LEVEL(2) | \ CPUID_4_SELF_INIT_LEVEL; - if (cs->nr_threads > 1) { - *eax |= (cs->nr_threads - 1) << 14; - } *ebx = (L2_LINE_SIZE - 1) | \ ((L2_PARTITIONS - 1) << 12) | \ ((L2_ASSOCIATIVITY - 1) << 22); @@ -2133,6 +2126,12 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count, *ecx = 0; *edx = 0; break; + } + } + + /* We give out APIC IDs ourselves, so force bits 31..26 even for "-cpu host". */ + if (cs->nr_cores > 1) { + *eax |= (cs->nr_cores - 1) << 26; } break; case 5: