* [Qemu-devel] [PATCH] test for lm capable kernel.
@ 2009-10-14 17:09 Glauber Costa
2009-10-22 16:20 ` Anthony Liguori
2009-10-22 16:51 ` Avi Kivity
0 siblings, 2 replies; 4+ messages in thread
From: Glauber Costa @ 2009-10-14 17:09 UTC (permalink / raw)
To: qemu-devel; +Cc: aliguori
Don't save x86_64-specific msrs if our kernel does not support them.
Code is already in qemu-kvm.git, but the test function is slightly different.
It follows what the test for msr_start does.
Signed-off-by: Glauber Costa <glommer@redhat.com>
---
target-i386/kvm.c | 37 +++++++++++++++++++++++++++----------
1 files changed, 27 insertions(+), 10 deletions(-)
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 7010999..0e69b57 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -15,6 +15,7 @@
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
+#include <sys/utsname.h>
#include <linux/kvm.h>
@@ -266,6 +267,20 @@ static int kvm_has_msr_star(CPUState *env)
return 0;
}
+static int lm_capable_kernel(void)
+{
+ static int lm_capable = -1;
+ struct utsname utsname;
+
+ if (lm_capable != -1) {
+ return lm_capable;
+ }
+
+ uname(&utsname);
+ lm_capable = (strcmp(utsname.machine, "x86_64") == 0);
+ return lm_capable;
+}
+
int kvm_arch_init(KVMState *s, int smp_cpus)
{
int ret;
@@ -478,11 +493,12 @@ static int kvm_put_msrs(CPUState *env)
kvm_msr_entry_set(&msrs[n++], MSR_STAR, env->star);
kvm_msr_entry_set(&msrs[n++], MSR_IA32_TSC, env->tsc);
#ifdef TARGET_X86_64
- /* FIXME if lm capable */
- kvm_msr_entry_set(&msrs[n++], MSR_CSTAR, env->cstar);
- kvm_msr_entry_set(&msrs[n++], MSR_KERNELGSBASE, env->kernelgsbase);
- kvm_msr_entry_set(&msrs[n++], MSR_FMASK, env->fmask);
- kvm_msr_entry_set(&msrs[n++], MSR_LSTAR, env->lstar);
+ if (lm_capable_kernel()) {
+ kvm_msr_entry_set(&msrs[n++], MSR_CSTAR, env->cstar);
+ kvm_msr_entry_set(&msrs[n++], MSR_KERNELGSBASE, env->kernelgsbase);
+ kvm_msr_entry_set(&msrs[n++], MSR_FMASK, env->fmask);
+ kvm_msr_entry_set(&msrs[n++], MSR_LSTAR, env->lstar);
+ }
#endif
msr_data.info.nmsrs = n;
@@ -611,11 +627,12 @@ static int kvm_get_msrs(CPUState *env)
msrs[n++].index = MSR_STAR;
msrs[n++].index = MSR_IA32_TSC;
#ifdef TARGET_X86_64
- /* FIXME lm_capable_kernel */
- msrs[n++].index = MSR_CSTAR;
- msrs[n++].index = MSR_KERNELGSBASE;
- msrs[n++].index = MSR_FMASK;
- msrs[n++].index = MSR_LSTAR;
+ if (lm_capable_kernel()) {
+ msrs[n++].index = MSR_CSTAR;
+ msrs[n++].index = MSR_KERNELGSBASE;
+ msrs[n++].index = MSR_FMASK;
+ msrs[n++].index = MSR_LSTAR;
+ }
#endif
msr_data.info.nmsrs = n;
ret = kvm_vcpu_ioctl(env, KVM_GET_MSRS, &msr_data);
--
1.6.2.5
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [Qemu-devel] [PATCH] test for lm capable kernel.
2009-10-14 17:09 [Qemu-devel] [PATCH] test for lm capable kernel Glauber Costa
@ 2009-10-22 16:20 ` Anthony Liguori
2009-10-22 16:51 ` Avi Kivity
1 sibling, 0 replies; 4+ messages in thread
From: Anthony Liguori @ 2009-10-22 16:20 UTC (permalink / raw)
To: Glauber Costa; +Cc: qemu-devel
Glauber Costa wrote:
> Don't save x86_64-specific msrs if our kernel does not support them.
> Code is already in qemu-kvm.git, but the test function is slightly different.
> It follows what the test for msr_start does.
>
Repeat after me: "I will not use --target-list when submitting qemu
patches. I will not use --target-list when submitting qemu patches."
Fedora enables ccache by default. After one build, all future builds
are extremely fast in most cases. It's really not that bad :-)
> Signed-off-by: Glauber Costa <glommer@redhat.com>
> ---
> target-i386/kvm.c | 37 +++++++++++++++++++++++++++----------
> 1 files changed, 27 insertions(+), 10 deletions(-)
>
> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> index 7010999..0e69b57 100644
> --- a/target-i386/kvm.c
> +++ b/target-i386/kvm.c
> @@ -15,6 +15,7 @@
> #include <sys/types.h>
> #include <sys/ioctl.h>
> #include <sys/mman.h>
> +#include <sys/utsname.h>
>
> #include <linux/kvm.h>
>
> @@ -266,6 +267,20 @@ static int kvm_has_msr_star(CPUState *env)
> return 0;
> }
>
> +static int lm_capable_kernel(void)
> +{
> + static int lm_capable = -1;
> + struct utsname utsname;
> +
> + if (lm_capable != -1) {
> + return lm_capable;
> + }
> +
> + uname(&utsname);
> + lm_capable = (strcmp(utsname.machine, "x86_64") == 0);
> + return lm_capable;
> +}
> +
>
This function is unused for qemu-system-i386.
Regards,
Anthony Liguori
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [Qemu-devel] [PATCH] test for lm capable kernel.
2009-10-14 17:09 [Qemu-devel] [PATCH] test for lm capable kernel Glauber Costa
2009-10-22 16:20 ` Anthony Liguori
@ 2009-10-22 16:51 ` Avi Kivity
2009-10-22 16:56 ` Glauber Costa
1 sibling, 1 reply; 4+ messages in thread
From: Avi Kivity @ 2009-10-22 16:51 UTC (permalink / raw)
To: Glauber Costa; +Cc: aliguori, qemu-devel
On 10/14/2009 07:09 PM, Glauber Costa wrote:
> Don't save x86_64-specific msrs if our kernel does not support them.
> Code is already in qemu-kvm.git, but the test function is slightly different.
> It follows what the test for msr_start does.
>
Can't we use KVM_GET_MSR_LIST to see which msrs are supported instead?
--
error compiling committee.c: too many arguments to function
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [Qemu-devel] [PATCH] test for lm capable kernel.
2009-10-22 16:51 ` Avi Kivity
@ 2009-10-22 16:56 ` Glauber Costa
0 siblings, 0 replies; 4+ messages in thread
From: Glauber Costa @ 2009-10-22 16:56 UTC (permalink / raw)
To: Avi Kivity; +Cc: aliguori, qemu-devel
On Thu, Oct 22, 2009 at 06:51:46PM +0200, Avi Kivity wrote:
> On 10/14/2009 07:09 PM, Glauber Costa wrote:
>> Don't save x86_64-specific msrs if our kernel does not support them.
>> Code is already in qemu-kvm.git, but the test function is slightly different.
>> It follows what the test for msr_start does.
>>
>
> Can't we use KVM_GET_MSR_LIST to see which msrs are supported instead?
that would be good, indeed.
Right now we're doing it for star, but we could keep the list and always
query it.
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2009-10-22 16:56 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2009-10-14 17:09 [Qemu-devel] [PATCH] test for lm capable kernel Glauber Costa
2009-10-22 16:20 ` Anthony Liguori
2009-10-22 16:51 ` Avi Kivity
2009-10-22 16:56 ` Glauber Costa
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).