* [uq/master patch 0/2] kvm max vcpu limit fixes
@ 2013-08-12 19:56 Marcelo Tosatti
2013-08-12 19:56 ` [uq/master patch 1/2] kvm-all.c: use recommended max vcpus limit Marcelo Tosatti
2013-08-12 19:56 ` [uq/master patch 2/2] kvm-all.c: max_cpus should not exceed KVM vcpu limit Marcelo Tosatti
0 siblings, 2 replies; 6+ messages in thread
From: Marcelo Tosatti @ 2013-08-12 19:56 UTC (permalink / raw)
To: kvm; +Cc: pbonzini, gleb
1) Use recommended vcpu limit instead of max vcpu limit
2) Do not allow max_cpus > max_vcpus
^ permalink raw reply [flat|nested] 6+ messages in thread
* [uq/master patch 1/2] kvm-all.c: use recommended max vcpus limit
2013-08-12 19:56 [uq/master patch 0/2] kvm max vcpu limit fixes Marcelo Tosatti
@ 2013-08-12 19:56 ` Marcelo Tosatti
2013-08-18 15:28 ` Paolo Bonzini
2013-08-12 19:56 ` [uq/master patch 2/2] kvm-all.c: max_cpus should not exceed KVM vcpu limit Marcelo Tosatti
1 sibling, 1 reply; 6+ messages in thread
From: Marcelo Tosatti @ 2013-08-12 19:56 UTC (permalink / raw)
To: kvm; +Cc: pbonzini, gleb, Marcelo Tosatti
[-- Attachment #1: kvm-all-use-cap-nr-vcpus-first --]
[-- Type: text/plain, Size: 940 bytes --]
Commit 8c3ba334f8588e1d5099f8602cf01897720e0eca, "KVM: x86: Raise the
hard VCPU count limit", upstream introduced the notion of a recommended
vcpu max limit.
Switch the order so the recommended vcpu max limit is used instead of
the actual max vcpu limit.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Index: qemu/kvm-all.c
===================================================================
--- qemu.orig/kvm-all.c
+++ qemu/kvm-all.c
@@ -1321,11 +1321,11 @@ static int kvm_max_vcpus(KVMState *s)
* procedure from the kernel API documentation to cope with
* older kernels that may be missing capabilities.
*/
- ret = kvm_check_extension(s, KVM_CAP_MAX_VCPUS);
+ ret = kvm_check_extension(s, KVM_CAP_NR_VCPUS);
if (ret) {
return ret;
}
- ret = kvm_check_extension(s, KVM_CAP_NR_VCPUS);
+ ret = kvm_check_extension(s, KVM_CAP_MAX_VCPUS);
if (ret) {
return ret;
}
^ permalink raw reply [flat|nested] 6+ messages in thread
* [uq/master patch 2/2] kvm-all.c: max_cpus should not exceed KVM vcpu limit
2013-08-12 19:56 [uq/master patch 0/2] kvm max vcpu limit fixes Marcelo Tosatti
2013-08-12 19:56 ` [uq/master patch 1/2] kvm-all.c: use recommended max vcpus limit Marcelo Tosatti
@ 2013-08-12 19:56 ` Marcelo Tosatti
2013-08-20 16:44 ` Paolo Bonzini
1 sibling, 1 reply; 6+ messages in thread
From: Marcelo Tosatti @ 2013-08-12 19:56 UTC (permalink / raw)
To: kvm; +Cc: pbonzini, gleb, Marcelo Tosatti
[-- Attachment #1: kvm-all-check-max-cpus --]
[-- Type: text/plain, Size: 684 bytes --]
maxcpus, which specifies the maximum number of hotpluggable CPUs,
should not exceed KVM's vcpu limit.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Index: qemu/kvm-all.c
===================================================================
--- qemu.orig/kvm-all.c
+++ qemu/kvm-all.c
@@ -1391,6 +1391,13 @@ int kvm_init(void)
goto err;
}
+ if (max_cpus > max_vcpus) {
+ ret = -EINVAL;
+ fprintf(stderr, "Number of max_cpus requested (%d) exceeds max cpus "
+ "supported by KVM (%d)\n", max_cpus, max_vcpus);
+ goto err;
+ }
+
s->vmfd = kvm_ioctl(s, KVM_CREATE_VM, 0);
if (s->vmfd < 0) {
#ifdef TARGET_S390X
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [uq/master patch 1/2] kvm-all.c: use recommended max vcpus limit
2013-08-12 19:56 ` [uq/master patch 1/2] kvm-all.c: use recommended max vcpus limit Marcelo Tosatti
@ 2013-08-18 15:28 ` Paolo Bonzini
2013-08-18 16:15 ` Marcelo Tosatti
0 siblings, 1 reply; 6+ messages in thread
From: Paolo Bonzini @ 2013-08-18 15:28 UTC (permalink / raw)
To: Marcelo Tosatti; +Cc: kvm, gleb
Il 12/08/2013 21:56, Marcelo Tosatti ha scritto:
> Commit 8c3ba334f8588e1d5099f8602cf01897720e0eca, "KVM: x86: Raise the
> hard VCPU count limit", upstream introduced the notion of a recommended
> vcpu max limit.
>
> Switch the order so the recommended vcpu max limit is used instead of
> the actual max vcpu limit.
>
> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
>
> Index: qemu/kvm-all.c
> ===================================================================
> --- qemu.orig/kvm-all.c
> +++ qemu/kvm-all.c
> @@ -1321,11 +1321,11 @@ static int kvm_max_vcpus(KVMState *s)
> * procedure from the kernel API documentation to cope with
> * older kernels that may be missing capabilities.
> */
> - ret = kvm_check_extension(s, KVM_CAP_MAX_VCPUS);
> + ret = kvm_check_extension(s, KVM_CAP_NR_VCPUS);
> if (ret) {
> return ret;
> }
> - ret = kvm_check_extension(s, KVM_CAP_NR_VCPUS);
> + ret = kvm_check_extension(s, KVM_CAP_MAX_VCPUS);
> if (ret) {
> return ret;
> }
>
>
This would break "working" configurations. Perhaps we should just warn
if the VCPU limit exceeds KVM_CAP_NR_VCPUS, and fail if the VCPU limit
exceeds KVM_CAP_MAX_VCPUS.
Patch 2 is fine, ok to apply it (since it fixes a real bug) and then you
can work on top of it?
Paolo
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [uq/master patch 1/2] kvm-all.c: use recommended max vcpus limit
2013-08-18 15:28 ` Paolo Bonzini
@ 2013-08-18 16:15 ` Marcelo Tosatti
0 siblings, 0 replies; 6+ messages in thread
From: Marcelo Tosatti @ 2013-08-18 16:15 UTC (permalink / raw)
To: Paolo Bonzini; +Cc: kvm, gleb
On Sun, Aug 18, 2013 at 05:28:28PM +0200, Paolo Bonzini wrote:
> Il 12/08/2013 21:56, Marcelo Tosatti ha scritto:
> > Commit 8c3ba334f8588e1d5099f8602cf01897720e0eca, "KVM: x86: Raise the
> > hard VCPU count limit", upstream introduced the notion of a recommended
> > vcpu max limit.
> >
> > Switch the order so the recommended vcpu max limit is used instead of
> > the actual max vcpu limit.
> >
> > Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
> >
> > Index: qemu/kvm-all.c
> > ===================================================================
> > --- qemu.orig/kvm-all.c
> > +++ qemu/kvm-all.c
> > @@ -1321,11 +1321,11 @@ static int kvm_max_vcpus(KVMState *s)
> > * procedure from the kernel API documentation to cope with
> > * older kernels that may be missing capabilities.
> > */
> > - ret = kvm_check_extension(s, KVM_CAP_MAX_VCPUS);
> > + ret = kvm_check_extension(s, KVM_CAP_NR_VCPUS);
> > if (ret) {
> > return ret;
> > }
> > - ret = kvm_check_extension(s, KVM_CAP_NR_VCPUS);
> > + ret = kvm_check_extension(s, KVM_CAP_MAX_VCPUS);
> > if (ret) {
> > return ret;
> > }
> >
> >
>
> This would break "working" configurations. Perhaps we should just warn
> if the VCPU limit exceeds KVM_CAP_NR_VCPUS, and fail if the VCPU limit
> exceeds KVM_CAP_MAX_VCPUS.
>
> Patch 2 is fine, ok to apply it (since it fixes a real bug) and then you
> can work on top of it?
OK, please apply patch 2.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [uq/master patch 2/2] kvm-all.c: max_cpus should not exceed KVM vcpu limit
2013-08-12 19:56 ` [uq/master patch 2/2] kvm-all.c: max_cpus should not exceed KVM vcpu limit Marcelo Tosatti
@ 2013-08-20 16:44 ` Paolo Bonzini
0 siblings, 0 replies; 6+ messages in thread
From: Paolo Bonzini @ 2013-08-20 16:44 UTC (permalink / raw)
To: Marcelo Tosatti; +Cc: kvm, gleb
Il 12/08/2013 21:56, Marcelo Tosatti ha scritto:
> maxcpus, which specifies the maximum number of hotpluggable CPUs,
> should not exceed KVM's vcpu limit.
>
> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
>
> Index: qemu/kvm-all.c
> ===================================================================
> --- qemu.orig/kvm-all.c
> +++ qemu/kvm-all.c
> @@ -1391,6 +1391,13 @@ int kvm_init(void)
> goto err;
> }
>
> + if (max_cpus > max_vcpus) {
> + ret = -EINVAL;
> + fprintf(stderr, "Number of max_cpus requested (%d) exceeds max cpus "
> + "supported by KVM (%d)\n", max_cpus, max_vcpus);
> + goto err;
> + }
> +
> s->vmfd = kvm_ioctl(s, KVM_CREATE_VM, 0);
> if (s->vmfd < 0) {
> #ifdef TARGET_S390X
>
>
> --
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> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
I applied this patch to uq/master. Thanks,
Paolo
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2013-08-20 16:45 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2013-08-12 19:56 [uq/master patch 0/2] kvm max vcpu limit fixes Marcelo Tosatti
2013-08-12 19:56 ` [uq/master patch 1/2] kvm-all.c: use recommended max vcpus limit Marcelo Tosatti
2013-08-18 15:28 ` Paolo Bonzini
2013-08-18 16:15 ` Marcelo Tosatti
2013-08-12 19:56 ` [uq/master patch 2/2] kvm-all.c: max_cpus should not exceed KVM vcpu limit Marcelo Tosatti
2013-08-20 16:44 ` Paolo Bonzini
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