linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v2] KVM: x86: Assign correct value to array.maxnent
@ 2020-06-04  4:16 Xiaoyao Li
  2020-06-04 15:12 ` Sean Christopherson
  0 siblings, 1 reply; 3+ messages in thread
From: Xiaoyao Li @ 2020-06-04  4:16 UTC (permalink / raw)
  To: Sean Christopherson, Paolo Bonzini; +Cc: kvm, linux-kernel, Xiaoyao Li

Delay the assignment of array.maxnent to use correct value for the case
cpuid->nent > KVM_MAX_CPUID_ENTRIES.

Fixes: e53c95e8d41e ("KVM: x86: Encapsulate CPUID entries and metadata in struct")
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
---
v2:
   - remove "const" of maxnent to fix build error.
---
 arch/x86/kvm/cpuid.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 253b8e875ccd..3d88ddf781d0 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -426,7 +426,7 @@ EXPORT_SYMBOL_GPL(kvm_set_cpu_caps);
 
 struct kvm_cpuid_array {
 	struct kvm_cpuid_entry2 *entries;
-	const int maxnent;
+	int maxnent;
 	int nent;
 };
 
@@ -870,7 +870,6 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
 
 	struct kvm_cpuid_array array = {
 		.nent = 0,
-		.maxnent = cpuid->nent,
 	};
 	int r, i;
 
@@ -887,6 +886,8 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
 	if (!array.entries)
 		return -ENOMEM;
 
+	array.maxnent = cpuid->nent;
+
 	for (i = 0; i < ARRAY_SIZE(funcs); i++) {
 		r = get_cpuid_func(&array, funcs[i], type);
 		if (r)
-- 
2.18.2


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH v2] KVM: x86: Assign correct value to array.maxnent
  2020-06-04  4:16 [PATCH v2] KVM: x86: Assign correct value to array.maxnent Xiaoyao Li
@ 2020-06-04 15:12 ` Sean Christopherson
  2020-06-04 16:21   ` Paolo Bonzini
  0 siblings, 1 reply; 3+ messages in thread
From: Sean Christopherson @ 2020-06-04 15:12 UTC (permalink / raw)
  To: 20200604024304.14643-1-xiaoyao.li
  Cc: Paolo Bonzini, kvm, linux-kernel, Xiaoyao Li

On Thu, Jun 04, 2020 at 12:16:36PM +0800, Xiaoyao Li wrote:
> Delay the assignment of array.maxnent to use correct value for the case
> cpuid->nent > KVM_MAX_CPUID_ENTRIES.
> 
> Fixes: e53c95e8d41e ("KVM: x86: Encapsulate CPUID entries and metadata in struct")
> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
> ---
> v2:
>    - remove "const" of maxnent to fix build error.
> ---
>  arch/x86/kvm/cpuid.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index 253b8e875ccd..3d88ddf781d0 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -426,7 +426,7 @@ EXPORT_SYMBOL_GPL(kvm_set_cpu_caps);
>  
>  struct kvm_cpuid_array {
>  	struct kvm_cpuid_entry2 *entries;
> -	const int maxnent;
> +	int maxnent;
>  	int nent;
>  };
>  
> @@ -870,7 +870,6 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
>  
>  	struct kvm_cpuid_array array = {
>  		.nent = 0,
> -		.maxnent = cpuid->nent,
>  	};
>  	int r, i;
>  
> @@ -887,6 +886,8 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
>  	if (!array.entries)
>  		return -ENOMEM;
>  
> +	array.maxnent = cpuid->nent;

Eh, I'd vote to just do:

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 253b8e875ccd..1e5b1ee75a76 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -870,7 +870,7 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,

        struct kvm_cpuid_array array = {
                .nent = 0,
-               .maxnent = cpuid->nent,
+               .maxnent = min(cpuid->nent, (u32)KVM_MAX_CPUID_ENTRIES),
        };
        int r, i;



> +
>  	for (i = 0; i < ARRAY_SIZE(funcs); i++) {
>  		r = get_cpuid_func(&array, funcs[i], type);
>  		if (r)
> -- 
> 2.18.2
> 

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH v2] KVM: x86: Assign correct value to array.maxnent
  2020-06-04 15:12 ` Sean Christopherson
@ 2020-06-04 16:21   ` Paolo Bonzini
  0 siblings, 0 replies; 3+ messages in thread
From: Paolo Bonzini @ 2020-06-04 16:21 UTC (permalink / raw)
  To: Sean Christopherson; +Cc: kvm, linux-kernel, Xiaoyao Li

On 04/06/20 17:12, Sean Christopherson wrote:
> On Thu, Jun 04, 2020 at 12:16:36PM +0800, Xiaoyao Li wrote:
>> Delay the assignment of array.maxnent to use correct value for the case
>> cpuid->nent > KVM_MAX_CPUID_ENTRIES.
>>
>> Fixes: e53c95e8d41e ("KVM: x86: Encapsulate CPUID entries and metadata in struct")
>> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
>> ---
>> v2:
>>    - remove "const" of maxnent to fix build error.
>> ---
>>  arch/x86/kvm/cpuid.c | 5 +++--
>>  1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
>> index 253b8e875ccd..3d88ddf781d0 100644
>> --- a/arch/x86/kvm/cpuid.c
>> +++ b/arch/x86/kvm/cpuid.c
>> @@ -426,7 +426,7 @@ EXPORT_SYMBOL_GPL(kvm_set_cpu_caps);
>>  
>>  struct kvm_cpuid_array {
>>  	struct kvm_cpuid_entry2 *entries;
>> -	const int maxnent;
>> +	int maxnent;
>>  	int nent;
>>  };
>>  
>> @@ -870,7 +870,6 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
>>  
>>  	struct kvm_cpuid_array array = {
>>  		.nent = 0,
>> -		.maxnent = cpuid->nent,
>>  	};
>>  	int r, i;
>>  
>> @@ -887,6 +886,8 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
>>  	if (!array.entries)
>>  		return -ENOMEM;
>>  
>> +	array.maxnent = cpuid->nent;
> 
> Eh, I'd vote to just do:
> 
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index 253b8e875ccd..1e5b1ee75a76 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -870,7 +870,7 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
> 
>         struct kvm_cpuid_array array = {
>                 .nent = 0,
> -               .maxnent = cpuid->nent,
> +               .maxnent = min(cpuid->nent, (u32)KVM_MAX_CPUID_ENTRIES),
>         };
>         int r, i;
> 

Both are fine, I've queued Xiaoyao's patch.

Paolo


^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2020-06-04 16:22 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-06-04  4:16 [PATCH v2] KVM: x86: Assign correct value to array.maxnent Xiaoyao Li
2020-06-04 15:12 ` Sean Christopherson
2020-06-04 16:21   ` Paolo Bonzini

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).