kvm-devel

[kvm-devel] [PATCH 0/2] KVM clock - userspace part

[Glauber de O. C. <gc...@re...>]

These are pretty straightforward. Just probe the host, and advertise the guest

[kvm-devel] [PATCH 1/2] include kvm_para.h

[Glauber de O. C. <gc...@re...>]

have qemu-kvm to include kvm_para, allowing access to paravirt definitions

Signed-off-by: Glauber de Oliveira Costa <gc...@re...>
---
 qemu/qemu-kvm-x86.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/qemu/qemu-kvm-x86.c b/qemu/qemu-kvm-x86.c
index c79ca36..21ec112 100644
--- a/qemu/qemu-kvm-x86.c
+++ b/qemu/qemu-kvm-x86.c
@@ -14,6 +14,7 @@ extern int kvm_irqchip;
 #include <libkvm.h>
 #include <pthread.h>
 #include <sys/utsname.h>
+#include <linux/kvm_para.h>
 
 #define MSR_IA32_TSC		0x10
 
-- 
1.5.0.6

[kvm-devel] [PATCH 2/2] fill cpuid with clocksource information

[Glauber de O. C. <gc...@re...>]

In this patch, we probe the host checking for clocksource capabilities.
In case it is found, it is advertised to the guest through the appropriate
cpuid mechanism

Signed-off-by: Glauber de Oliveira Costa <gc...@re...>
---
 qemu/qemu-kvm-x86.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/qemu/qemu-kvm-x86.c b/qemu/qemu-kvm-x86.c
index 21ec112..c008cb7 100644
--- a/qemu/qemu-kvm-x86.c
+++ b/qemu/qemu-kvm-x86.c
@@ -517,6 +517,10 @@ int kvm_arch_qemu_init_env(CPUState *cenv)
     int cpuid_nent = 0;
     CPUState copy;
     uint32_t i, limit;
+    int has_clocksource = 0;
+#ifdef KVM_CAP_CLOCKSOURCE
+    has_clocksource = kvm_check_extension(kvm_context, KVM_CAP_CLOCKSOURCE);
+#endif
 
     copy = *cenv;
 
@@ -534,7 +538,7 @@ int kvm_arch_qemu_init_env(CPUState *cenv)
     pv_ent = &cpuid_ent[cpuid_nent++];
     memset(pv_ent, 0, sizeof(*pv_ent));
     pv_ent->function = KVM_CPUID_FEATURES;
-    pv_ent->eax = 0;
+    pv_ent->eax = (has_clocksource << KVM_FEATURE_CLOCKSOURCE);
 #endif
 
     copy.regs[R_EAX] = 0;
-- 
1.5.0.6

Re: [kvm-devel] [PATCH 1/2] include kvm_para.h

[Avi K. <av...@qu...>]

Glauber de Oliveira Costa wrote:
> have qemu-kvm to include kvm_para, allowing access to paravirt definitions
>
> Signed-off-by: Glauber de Oliveira Costa <gc...@re...>
> ---
>  qemu/qemu-kvm-x86.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/qemu/qemu-kvm-x86.c b/qemu/qemu-kvm-x86.c
> index c79ca36..21ec112 100644
> --- a/qemu/qemu-kvm-x86.c
> +++ b/qemu/qemu-kvm-x86.c
> @@ -14,6 +14,7 @@ extern int kvm_irqchip;
>  #include <libkvm.h>
>  #include <pthread.h>
>  #include <sys/utsname.h>
> +#include <linux/kvm_para.h>
>  

IIRC, early versions of kvm_para.h were userspace unfriendly, so we need 
a version code check (or better, a KVM_CAP_ check) around this.

-- 
Any sufficiently difficult bug is indistinguishable from a feature.

Re: [kvm-devel] [PATCH 1/2] include kvm_para.h

[Glauber de O. C. <gc...@re...>]

Avi Kivity wrote:
> Glauber de Oliveira Costa wrote:
>> have qemu-kvm to include kvm_para, allowing access to paravirt 
>> definitions
>>
>> Signed-off-by: Glauber de Oliveira Costa <gc...@re...>
>> ---
>>  qemu/qemu-kvm-x86.c |    1 +
>>  1 files changed, 1 insertions(+), 0 deletions(-)
>>
>> diff --git a/qemu/qemu-kvm-x86.c b/qemu/qemu-kvm-x86.c
>> index c79ca36..21ec112 100644
>> --- a/qemu/qemu-kvm-x86.c
>> +++ b/qemu/qemu-kvm-x86.c
>> @@ -14,6 +14,7 @@ extern int kvm_irqchip;
>>  #include <libkvm.h>
>>  #include <pthread.h>
>>  #include <sys/utsname.h>
>> +#include <linux/kvm_para.h>
>>  
> 
> IIRC, early versions of kvm_para.h were userspace unfriendly, so we need 
> a version code check (or better, a KVM_CAP_ check) around this.
> 
No need. including kvm_para.h in userspace unfriendly tools won't break 
anything. Code that handles it userspace is already enclosed in the 
KVM_CAP_ check.

(well, in reality, I forgot to enclose one line with it. But it's a bug,
and will be fixed in the series I'm about to shoot out.